ADHD symptoms in children are associated with unusual interactions between the frontal cortex and deep centers of the brain where information is processed, according to a recent report in the American Journal of Psychiatry.¹ These findings may help inform additional research into the ADHD brain that leads to more effective treatments and interventions.

A research team from the National Institute of Mental Health (NIMH) and National Human Genome Research found children with ADHD demonstrated heightened connectivity between brain structures involved in learning, movement, and reward, and frontal areas of the brain that regulate emotion, attention, and behavior.

“The present findings suggest that these brain alterations are specifically associated with ADHD and are not indicative of general features of childhood psychopathology or influenced by comorbid symptoms,” the study’s authors wrote.

Researchers have long suspected that ADHD symptoms result from atypical interactions between the frontal cortex and these deep information-processing brain structures. However, the study’s authors noted that prior studies testing this model returned mixed results, possibly due to the small size of the studies they suggested.

The present study examined more than 10,000 functional brain images of 1,696 youth with ADHD and 6,737 without ADHD aged 6 to 18. It was the “largest study to date on changes in subcortical-cortical connectivity in ADHD,” the study’s authors wrote.

The findings underscore the need for more research regarding the association between brain connectivity and ADHD symptoms, the genetic aspects of ADHD, and how brain connectivity patterns relate to treatment outcomes.

Source

¹Luke J. Norman, Gustavo Sudre, Jolie Price, Philip Shaw. (2024). Subcortico-Cortical Dysconnectivity in ADHD: A Voxel-Wise Mega-Analysis Across Multiple Cohorts. American Journal of Psychiatry. DOI: 10.1176/appi.ajp.20230026

The link between parental experiences and child outcomes is well established, but research has generally focused on the prenatal period (e.g., the effects of smoking, stress, or diet during pregnancy) or the postnatal period (e.g., the impact of different parenting practices). More recent is the idea that parents may influence their children’s lives and health even before conception. In animal studies, exposure to trauma, alcohol use, or poor diet before conception has been found to alter epigenetic regulation in reproductive cells (eggs, sperm), influencing the offspring’s own epigenetic makeup and future behavior.

Epigenetics refers to a set of biological mechanisms that regulate when (in time) and where (in our body) genes are activated or switched off. Environmental exposures can influence these mechanisms.

The Challenges of Studying Humans

Most of the evidence for preconception effects comes from studies using animal models, which show that certain parental exposures before conception, such as diet and stress, can lead to differences in brain development, behavior, and disease risk in their offspring. While certainly thought-provoking, these findings currently pose more questions than they answer.

One such question: Do these findings generalize to humans? Clearly, experimental studies using animal models differ from human studies, which are typically observational. Animal studies can tightly control a subject’s environment and measure the effect of a specific exposure across generations while keeping all other factors constant (e.g., genetics or environmental factors). Such control is not possible with humans. Rather, studies in humans tend to measure as many variables as possible in an individual’s environment and life without interfering with them (observing rather than experimenting), which makes it much more difficult to establish causality.

So far, a handful of human studies have provided indirect support for preconception effects (e.g., the impact on offspring of parents and grandparents affected by World War II). However, it is difficult to establish whether preconception exposure or other related factors explain these effects. For example, preconception trauma exposure may affect parental mental health and increase risky behaviors, such as substance use, which may affect a child’s environment and development.

[New Class! The Adult’s Guide to ADHD Diagnosis]

Emerging Research on Epigenetics & Preconception

Multi-generational, well-characterized studies are beginning to emerge, opening unprecedented opportunities for exploring preconception effects in humans.

Another important question: Through what mechanisms do preconception effects occur? The effects may occur through epigenetic mechanisms influenced by the environment, affecting a person’s biology and health. Research suggests the link between parental experiences and offspring health outcomes may also occur along a biological route.

To what extent do these epigenetic mechanisms contribute to preconceptional effects in humans? To date, very few studies in humans have begun to explore epigenetic differences in sperm and eggs and whether they relate to their offspring’s health.

Moving the field forward will require large investments in studies that can collect epigenetic data in both parents and children and at different life stages (e.g., preconception, pregnancy, postnatal), which is expensive and logistically challenging. However, the rise of longitudinal multi-generational studies, together with the decreasing costs of epigenetic profiling and rapid methodological advances to handle this large and complex data, will soon enable us to overcome these barriers.

[Self-Test: Do I Have ADHD? Symptoms in Adults]

In the meantime, recognizing that both biological parents contribute to the health and development of the child, perhaps even before conception, is an exciting and important scientific development. This perspective helps counteract the focus on mothers, and it can serve to mitigate self-blame when a child is diagnosed with a condition. At the same time, we caution that the biological and epigenetic work on preconception effects largely relies on animal studies. Its relevance to humans is still unclear. However, we do know these possibilities warrant further human study.

Joel T. Nigg, Ph.D., is a professor of psychiatry and behavioral neuroscience and the director of the Center for ADHD Research at the Oregon Health & Science University in Portland, Oregon.

Charlotte A.M. Cecil, Ph.D., is an associate professor in biological psychopathology at the Department of Child and Adolescent Psychiatry at the Erasmus Medical Centre, the Netherlands.

Isabelle M. Mansuy, Ph.D., is a professor in neuroepigenetics at the Faculty of Medicine of the University of Zurich, Switzerland.

Epigenetic and Preconception Experiences: Next Steps

• Read: The Future of ADHD Research Looks Like This
• Read: Is ADHD Genetic? Yes and No
• Read: What Causes ADHD? Culture Vs. Biology
• Download: Free Guide to Health & Fitness: Lifestyle Changes for Adults with ADHD

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The association between Bisphenol-A (BPA) exposure and neurodevelopmental disorders is linked to a compromised metabolic process that powers plasticizer detoxification, according to a study published in PLoS ONE that expands on existing evidence linking BPA to autism spectrum disorder (ASD) and extends this finding to include attention-deficit hyperactivity disorder (ADHD).¹

Glucuronidation is a metabolic process that eliminates harmful drugs, toxins, and carcinogens from the body through urine. BPA is typically metabolized quickly; when glucuronidation is impaired, the body is exposed to the adverse effects of BPA for longer. This new research, which studied the urine samples of 149 children aged 3 to 16, found that glucuronidation efficiency for BPA was reduced by 17% for children with ADHD and by 11% for children with ASD, compared to controls.

Humans are exposed to BPA mainly through food packaging, contaminated food or water, or inhalation of plastic airborne particles. Between 2009 and 2010, the U.S. National Health and Nutrition Examination Survey (NHANES) detected BPA in 92% of urine samples in the general population, with slightly higher levels found in women and children.² A study cited by the researchers showed higher urinary concentrations of BPA in children with neurodivergent conditions.³ However, according to the FDA, the levels of BPA found in food products are not a threat to human health and safety.⁴

“How important plasticizer-originated neurodevelopmental disorder is in the overall occurrence of these disorders is not known, but it must account for a significant proportion or it would not have been so easy to detect in a metabolic study of moderate size such as this study,” the researchers wrote.

Researchers built on a previous study from 2015, which showed that the efficiency of glucuronidation of BPA metabolites was lower in children with ASD.⁵ They extended these findings to include ADHD and ruled out other plasticizer sub-pathways in the current study.

“There is nothing new about the efficiency of glucuronidation affecting metabolism and being associated with disease,” they said. “What is new is that we show this is also a plausible mechanism for ASD and ADHD.”

The use of common plasticizers and phthalates has been widespread since the 1950s to make products more flexible and durable. Exposure doesn’t always lead to harmful health effects,⁶ but recent decades have seen a decline in the use of plasticizers, particularly in products for young children. DEHP, an organic compound found in many plastic products, is prohibited in children’s toys and childcare articles, and BPA is now eliminated from baby bottles and sippy cups. At certain levels, bisphenol and phthalates can lead to reproductive harm, including infertility and early puberty.⁷

Disruptions to hormone functioning and gene mutations have also linked plasticizers to neurodevelopmental disorders, as cited by the researchers. Genetic susceptibility plays a central role. Many other factors are likely involved, says Charlotte Cecil, Ph.D. “The reality is that no single factor, either genetic or environmental, at the moment, has really emerged to be either necessary or sufficient to explain why a given individual might develop ADHD and particularly any impairment related to that,” she said in a recent webinar on epigenetic research and ADHD.

The study included 12 glucuronidation pathways, none of which showed an association with the control group. The diethylhexyl phthalate (DEHP) sub-pathway showed a similar but non-significant association with ADHD and ASD and was the only other notable sub-pathway besides BPA.

Sources

¹ Stein, T.P., Schluter, M.D., Steer, R.A., & Ming, X. (2023) Bisphenol a and phthalate metabolism in children with neurodevelopmental disorders. PLoS ONE 18(9): e0289841.https://doi.org/10.1371/journal.pone.0289841

² U.S. Environmental Protection Agency. (2013). America’s children and the environment, third edition. https://www.epa.gov/sites/default/files/2015-05/documents/biomonitoring-bpa.pdf

³ Minatoya M, Kishi R. (2021). A review of recent studies on bisphenol a and phthalate exposures and child neurodevelopment. International Journal of Environmental Research & Public Health, 18(7):30. https://doi.org/10.3390/ijerph18073585

⁴ U.S. Food and Drug Administration. (2023, April 20). Bisphenol a (BPA): use in food contact application. https://www.fda.gov/food/food-packaging-other-substances-come-contact-food-information-consumers/bisphenol-bpa-use-food-contact-application

⁵ Stein, T.P., Schluter, M.D., Steer, R.A., Guo, L., & Ming, X. (2015) Bisphenol a exposure in children with autism spectrum disorders. Autism Research, 8(3):272–83. https://onlinelibrary.wiley.com/doi/10.1002/aur.1444

⁶Centers for Disease Control and Prevention. (2021, April 5). Phthalates factsheet. https://www.cdc.gov/biomonitoring/Phthalates_FactSheet.html

⁷Callaghan, M.A., Alatorre-Hinojosa, S., Connors, L., Singh, R.D., & Thompson, J.A. (2021). Plasticizers and cardiovascular health: role of adipose tissue dysfunction. Frontiers in Pharmacology, 11. https://www.frontiersin.org/articles/10.3389/fphar.2020.626448

ADHD is likely influenced by both genetics and the environment, starting before birth. Research shows this, however the biological mechanisms of ADHD have been puzzling scientists for years. Research involving ADHD and epigenetics — a process that regulates how genes respond to environmental factors like diet, pollution, or stress — is still in its early stages. We do know that these processes are essential for healthy development, and that disruptions are thought to contribute to various health issues, including neurodevelopmental and psychiatric disorders.

Epigenetic research offers valuable insights into the development of ADHD, which could one day pave the way for improvements in early detection, treatment, and potentially even prevention. Although clinical applications remain in the distant future, these emerging clues hold promise for addressing ADHD more effectively in the long run.

In this webinar, you will:

• Learn how epigenetic processes regulate the interaction between genes and the environment, shaping our development and overall health
• Understand the effects of maternal health conditions and risk factors around the prenatal and perinatal periods
• Discover how epigenetic research is already making an impact in various health fields, improving screening, early disease detection (e.g., cancer), and guiding treatment decisions and drug-effectiveness assessments
• Hear about lessons learned from new epigenetic research on ADHD and what the future may hold in terms of potential clinical applications

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More on Epigenetics & ADHD

• Download: Is It Adult ADHD?
• Read: The Impacts of Environment, Lifestyle, and Stress
• Read: Prenatal and Early Life Risk Factors

Obtain a Certificate of Attendance

If you attended the live webinar on September 28, 2023, watched the video replay, or listened to the podcast, you may purchase a certificate of attendance option (cost: $10). Note: ADDitude does not offer CEU credits. Click here to purchase the certificate of attendance option »

Meet the Expert Speaker:

Dr. Charlotte Cecil is an Associate Professor in Biological Psychopathology at the Department of Child and Adolescent Psychiatry and Head of the inDEPTH Lab based at the Erasmus Medical Centre, the Netherlands. Her work aims to better understand factors influencing brain development and mental health from prenatal life to adolescence, in order to improve strategies for early risk detection and the prevention of chronic mental illnesses later in life. A key interest in her group is to identify how, at a biological level, genetic and environmental factors beginning in pregnancy come together to shape a child’s development, behavior, and health, with a particular focus on epigenetic mechanisms. She has authored more than 90 scientific articles and expert reviews on this topic, and has (co)lead multiple international efforts dedicated to better understanding and enhancing mental health during development, including the European collaborative projects TEMPO, MIND, FAMILY, EarlyCause, and HappyMums.

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The exact causes of ADHD are not yet known. ADHD is believed to be highly heritable —researchers have made strides in recent years identifying genes involved in the disorder — but it is also understood that ADHD may be influenced by non-inherited risk factors, such as trauma and stress. With scientific advances in the next decade or more, and perhaps with the aid of AI, we could see the diagnosis of many more subtypes of ADHD and new kinds of treatments involving novel therapies.

In this webinar, you will learn:

• About the current research involving genetic influences and environmental factors associated with ADHD
• How scientific discoveries could lead to the recognition of more than a dozen subtypes, and the implication of such findings
• How scientific advances may one day lead to the prevention of ADHD in utero or in the first two years of life
• About the future of promising therapies to retrain the brain to compensate for executive function weaknesses stemming from ADHD

Watch the Video Replay

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Download or Stream the Podcast Audio

Click the play button below to listen to this episode directly in your browser, click the symbol to download to listen later, or open in your podcasts app: Apple Podcasts; Google Podcasts; Audacy; Spotify; Amazon Music; iHeartRADIO.

More on ADHD Research, Diagnosis, and Treatment

• Download: How Common Is ADHD in Adults?
• Read: The Buzz Around Neuroimaging
• Read: The History of ADHD and Its Treatment

Obtain a Certificate of Attendance

If you attended the live webinar on August 23, 2023, watched the video replay, or listened to the podcast, you may purchase a certificate of attendance option (cost: $10). Note: ADDitude does not offer CEU credits. Click here to purchase the certificate of attendance option »

Meet the Expert Speaker

Peter S. Jensen, M.D., founded the REACH Institute in 2006 to improve access to mental health care for children by training healthcare professionals in the diagnosis and treatment of common disorders. Previously, Dr. Jensen was an Associate Director of Child and Adolescent Research at the National Institute of Mental Health (NIMH). He left NIMH and served as the founding director of the Center for the Advancement of Children’s Mental Health at Columbia University. While there, he developed the core methods REACH uses today to close the gap between science and practice. The strategy was to bring together leading scientists, mental health experts and agencies, primary care providers, parents, and schools to identify the best scientific findings available to help children. Then Dr. Jensen led REACH to implement, disseminate, and evaluate these methods.

The result was The REACH Institute’s first and most popular course, Patient-Centered Mental Health in Pediatric Primary Care. This course has trained more than 6,000 primary care providers to help children and teens with mental health issues.

Listener Testimonials

“This webinar was high-level and yet understandable! Such great information!”

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SYMPTOMS: What signs and symptoms point to ADHD in adults?

A: If you have adult ADHD, you may find it hard to remember information, organize tasks, finish work on time… | Keep reading on WebMD »

SUBTYPES: What are the key differences between inattentive, hyperactive, and combined-type ADHD in adults?

A: The three types of ADHD are primarily hyperactive and impulsive, primarily inattentive, and combined. Each presentation is… | Keep reading on ADDitude »

INATTENTIVE: What signs of inattentive ADHD in adults are commonly overlooked or mistaken?

A: The first overlooked sign of inattentive ADHD is difficulty completing tasks. People with inattentive ADHD are… | Keep reading on ADDitude »

THE ADHD BRAIN: What should I understand about how the ADHD brain is wired?

A: The ADHD nervous system regulates attention and emotions in different ways than the nervous system in those without… | Keep reading on ADDitude »

EXECUTIVE FUNCTIONS: What should I know about executive dysfunction and its relationship to ADHD?

A: The cognitive skills that help us plan, prioritize, and execute complex tasks are commonly tied to ADHD… | Keep reading on ADDitude »

NEUROSCIENCE: How does the neurology of ADHD help explain my challenges?

A: The ADHD nervous system is rarely at rest. It always wants to be engaged in something interesting and…” | Keep reading on ADDitude »

FIRST-PERSON: “I Branded Myself a Misunderstood Freak. But It Was ADHD All Along.”

“The psychologist listened as I spoke about my life. He then gave me that look people often give when I talk at 200 mph and asked, ‘What do you do when you’re calm?’ ‘I’m never calm!’ I told him, genuinely dumbfounded by this revelation.” | Keep reading on ADDitude »

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SYMPTOM TEST: ADHD IN ADULTS

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SYMPTOM TEST: INATTENTIVE ADHD

Symptoms can show up as procrastination and difficulty sustaining attention. | Take the self-test on ADDitude »

8-Part Guide to ADHD Diagnosis in Adults, from WebMD x ADDitude:

> DECISION 1: How can I better understand ADHD, its causes, and its manifestations?
DECISION 2: How can I understand the aspects of ADHD that might be new to my doctor?
DECISION 3: How can I improve my odds of an accurate ADHD evaluation?
DECISION 4: How can I find a professional to diagnose and treat my ADHD?
DECISION 5: What should a thorough evaluation for adult ADHD include and exclude?
DECISION 6: How can I be sure my ADHD evaluation screens for psychiatric comorbidities?
DECISION 7: How can I be sure my ADHD evaluation considers look-alike comorbidities?
DECISION 8: Should I also be screened for the sleep, eating, or other disorders?

The use of ADHD medication during pregnancy causes no impairment of a child’s neurodevelopment or physical growth, according to research published in Molecular Psychiatry.¹ A large population-based register study found in-utero exposure to medication for ADHD, including stimulants, did not impair a child’s neurodevelopment or growth compared to children whose mothers stopped taking ADHD medication prior to conception.

Research was conducted using data from Danish nationwide registers, including more than one million children born between 1998 and 2015. Of those, 898 children were delivered by mothers who started or continued taking ADHD medication during pregnancy; this became the study’s “exposed” group. The “unexposed” group included 1,270 children whose mothers discontinued — but had previously taken — ADHD medication before conception.

Prenatal & Postnatal Exposure to ADHD Medication

After adjusting for maternal demographic characteristics and psychiatric data, researchers found no difference in long-term neurodevelopmental or growth outcomes between the two groups. In other words, women could stop taking medication before conception or continue during pregnancy without putting their child at greater risk of neurodevelopmental psychiatric disorders (ADHD, ASD); neurodevelopmental impairments (vision, hearing, seizures, epilepsy); or growth impairments.

Though the percentage is small, the number of pregnant women taking ADHD medication has steadily increased over time.^{2, 3} In fact, ADHD medication is one of the most common medications prescribed during pregnancy.^{3, 4}

In a recent survey of ADDitude readers, 2.39% of 1,170 women who had been pregnant reported taking medication for their ADHD following conception. Many of those who did not take medication said they remained undiagnosed and untreated at the time of their pregnancies, and therefore had no prescribed medications. Just 2.58% took ADHD medication while breastfeeding.

If a woman decides to discontinue use while both pregnant and breastfeeding, she may go a year or longer without pharmacological treatment — a first-line treatment for ADHD.

“I stopped [taking] Adderall leading up until delivery, and had been told I couldn’t take it at all during breastfeeding,” wrote one 33-year-old woman in Texas. “I went back to work three months postpartum. I really struggled with symptoms and felt unable to do my job.

“I did some additional research… that suggested a low breastmilk transfer rate for Adderall, and an even lower rate with Ritalin. Five months postpartum, I brought that data to my GP, who agreed to prescribe 5mg of Ritalin twice daily. I continued exclusively breastfeeding for two more months, then did a combination of breastfeeding and formula until weaning completely when my daughter was nine months. At that time, my GP switched me back to Adderall. During this time, my daughter showed no adverse effects, remaining on her growth trajectory in the 90th percentile and sleeping like a champ!”

Impact on Children

The decision to cease or continue treatment for ADHD while pregnant is difficult, in large part because the effects of ADHD medication in utero are not well-documented. Due to the nature of the problem, research is limited to register studies like this most recent one — the second and largest long-term register study to examine the effects of ADHD medication during pregnancy.

In addition, the research is conflicting. A 2015 U.S. population-based study found that ADHD medication use in early pregnancy was associated with three specific, selected birth defects.⁵ Another U.S.-based study, published in 2017, suggested an increased risk of cardiovascular defects from prenatal exposure to methylphenidate — but not amphetamines.⁶

While exposed children faced no increased risks for common neurodevelopmental outcomes in the present study, researchers found that exposed children born to mothers who used other psychotropic medication during pregnancy were more likely to develop ADHD. This was also found when the mother had filled two or more prescriptions for ADHD medication during pregnancy.

Because the increased risk was limited to ADHD only, researchers speculate these results may be “driven by severity of maternal ADHD” through “higher disease liability for ADHD and through referral bias, that is, offspring of mothers with severe ADHD are assessed more carefully for ADHD.”

Impact on Women with ADHD

On average, women in the U.S. have their first child by age 27.⁷ According to the ADDitude survey, it’s around this time that women report a major impact caused by their ADHD symptoms. The majority — 64% to 70% of 2,010 respondents — said the overall impact of ADHD was major or life-altering in their 20s and 30s.

Half of survey respondents who had been pregnant said their ADHD symptoms remained stable during pregnancy. But following delivery, 56.7% of them said they experienced symptoms of postpartum depression. Around more than one-third told ADDitude these symptoms lasted for more than 6 months; for nearly 10%, postpartum depression lasted more than two years.

Similar findings were discovered in a 2020 survey conducted by the MGH Center for Women’s Mental Health. No significant changes in ADHD symptoms were reported by women during pregnancy, but those who chose to discontinue psychostimulant medication experienced a significant increase in postpartum depressive symptoms. Women who elected to adjust their ADHD medication use, or maintained the same prescription schedule, did not experience a significant change in depressive symptoms.

Limitations and Future Research

“Pregnant women who depend on stimulants for daily functioning must weigh the potential of exposing their fetus to unknown developmental risks against potential medical, financial, and other consequences to both mother and child that are associated with exacerbation of ADHD symptoms when stopping the medication, such as inability to maintain employment and unsafe driving,” the researchers stated.

ADHD medication in the present study included stimulants (methylphenidate, amphetamine, dexamphetamine, lisdexamphetamine) and other treatments (modafinil, atomoxetine, clonidine).

“The present study provides reassurance that several essential categories of child outcomes that could reasonably be suspected to be affected by stimulants, including body growth, neurodevelopment, and seizure risk, do not differ based on antenatal stimulant exposure.”

Compared to women without ADHD, the study’s sample population of women with ADHD tended to be younger at the time of childbirth, more likely to smoke during pregnancy, and more likely to have children born preterm or with low birth weight. This finding was consistent regardless of whether the mother took ADHD medication during pregnancy.

Finally, more research is needed to differentiate between the effects of ADHD medication types, dosage, and trimester. This study was limited to diagnoses formally entered into the Danish register. Future research should be expanded to include a larger sample population.

Sources

¹Madsen, K. B., Robakis, T. K., Liu, X., Momen, N., Larsson, H., Dreier, J. W., … Bergink, V. (2023). In utero exposure to ADHD medication and long-term offspring outcomes. Molecular Psychiatry, 1–8. doi: 10.1038/s41380-023-01992-6

²Lemelin, M., Boukhris, T., Zhao, J. P., Sheehy, O., & Bérard, A. (2021). Prevalence and determinants of attention deficit/hyperactivity disorder (ADHD) medication use during pregnancy: Results from the Quebec pregnancy/children cohort. Pharmacology research & perspectives, 9(3), e00781. https://doi.org/10.1002/prp2.781

³Haervig, K. B., Mortensen, L. H., Hansen, A. V., & Strandberg-Larsen, K. (2014). Use of ADHD medication during pregnancy from 1999 to 2010: A Danish register-based study. Pharmacoepidemiology and drug safety, 23(5), 526–533. https://doi.org/10.1002/pds.3600

⁴Louik, C., Kerr, S., Kelley, K. E., & Mitchell, A. A. (2015). Increasing use of ADHD medications in pregnancy. Pharmacoepidemiol Drug Saf, 24, 218– 220, doi: 10.1002/pds.3742.

⁵Anderson, K. N., Dutton, A. C., Broussard, C. S., Farr, S. L., Lind, J. N., Visser, S. N., Ailes, E. C., Shapira, S. K., Reefhuis, J., & Tinker, S. C. (2020). ADHD medication use during pregnancy and risk for selected birth defects: National birth defects prevention study, 1998-2011. Journal of Attention Disorders, 24(3), 479–489. https://doi.org/10.1177/1087054718759753

⁶Huybrechts, K. F., Bröms, G., Christensen, L. B., Einarsdóttir, K., Engeland, A., Furu, K., Gissler, M., Hernandez-Diaz, S., Karlsson, P., Karlstad, Ø., Kieler, H., Lahesmaa-Korpinen, A. M., Mogun, H., Nørgaard, M., Reutfors, J., Sørensen, H. T., Zoega, H., & Bateman, B. T. (2018). Association between methylphenidate and amphetamine use in pregnancy and risk of congenital malformations: A cohort study from the international pregnancy safety study consortium. JAMA psychiatry, 75(2), 167–175. https://doi.org/10.1001/jamapsychiatry.2017.3644

⁷Osterman, M.J.K., Hamilton, B.E., Martin, J.A., Driscoll, A.K., & Valenzuela, C.P. (2023). Births: Final data for 2021. National Vital Statistics Reports; 72(1). DOI: https://dx.doi. org/10.15620/cdc:122047.

From lead exposure and maternal stress during pregnancy to low birth weight, the list of prenatal and perinatal risk factors associated with ADHD seems to grow longer and longer with ongoing research. But there is much left to learn. The causal role of many exposures linked to ADHD is unclear; some appear to be artifacts of ADHD’s genetic element, while others are truly causal contributors. The other critical factor is that none of the risk factors cause ADHD every time; most children exposed to these risk factors do not develop ADHD.

Thus, it seems increasingly clear that genes and environments work together to shape development of the brain and behavior throughout life, but especially —and most dramatically — in very early life. ADHD, like other complex conditions, doesn’t have a single cause. Both nature and nurture influence its development.

Some prenatal and perinatal risk factors for ADHD are unavoidable and inevitable. Mothers grappling with their child’s ADHD diagnosis especially may place undue blame on themselves as they fixate on past events that could have contributed to their child’s ADHD. But science provides comforting truths: Exposure to risk factors does not guarantee ADHD, and early and effective treatment approaches can often mitigate the effects of previous complications and improve outcomes.

ADHD Risk Factors: What We Know

Prenatal Risk Factors

Teratogens: Alcohol, Smoking, and Other Substances

Teratogens are substances and agents that could harm a developing fetus during pregnancy. Some teratogens have been linked to ADHD, though association should not be mistaken for causality.

[Read: Is ADHD Genetic? Yes and No]

Alcohol

Children whose mothers consumed alcohol during pregnancy were at 1.55 times the risk for developing ADHD compared to children whose mothers did not consume alcohol while pregnant, according to a 2015 study of roughly 20,000 parents.¹ Other studies have found mixed evidence on prenatal alcohol exposure and ADHD risk.^{2 3}

Drinking alcohol during pregnancy can cause a group of conditions called fetal alcohol spectrum disorders (FASD), which are associated with some symptoms and features linked to ADHD, including behavioral challenges, inattention, learning disabilities, poor memory, hyperactivity, and impulsivity. ⁴

In many cases, FASD is overlooked altogether and even misdiagnosed as ADHD. ^{5 6}

Tobacco Use

Maternal prenatal smoking increases risk for ADHD in children by more than one and a half times, according to a 2020 review of 12 large studies.⁷ Other studies have found that paternal smoking before and during pregnancy increases risk for ADHD in offspring.^{1 8 9}

However, while smoking in pregnancy is a major correlate of ADHD, it’s probably not a causal factor. Studies that controlled for genetic effects found that the maternal smoking association to ADHD largely disappeared.

[Read: What Causes ADHD? Culture Vs. Biology]

Drugs and Other Substances

• Opioids: Children whose mothers used opioids during pregnancy had more than double the risk for ADHD compared to those whose mothers did not use the drug, according to a 2022 study of about 3,000 children.² The same study found that risk for ADHD increases with exposure to multiple substances, including tobacco and cannabis.
• Acetaminophen exposure in the womb may increase a child’s risk for ADHD.¹⁰ It’s unclear whether there are time periods when the developing brain may be most sensitive to acetaminophen exposure. The FDA urges pregnant parents to consult with a doctor before taking pain medication.

But, as with smoking, we do not yet know if these effects are causal independent of genetic effects.

Maternal Health Issues

Maternal Metabolic Syndrome

Maternal obesity, hypertension, diabetes, and related conditions before and during pregnancy are associated with increased risk for ADHD, autism, and other neurodevelopmental disorders in offspring.^{12 13} While researchers are still investigating the connection, the risk for these effects in isolation appears small, especially considering the prevalence of these conditions at large. Still, they are effects that helps us learn about mechanisms that are possibly tied to ADHD.

Emotional Stress and/or Trauma

Maternal exposure to stress or trauma, if it’s high, can influence offspring behavior and temperament. What’s more, chronic prenatal stress increases the likelihood that a child will have ADHD or other conditions.

One 2018 study found that mothers who experienced high levels of stress during their pregnancy were more than twice as likely as less-stressed mothers to have a child diagnosed with ADHD or conduct disorder.¹⁴

Birth Trauma and Delivery Complications

Oxygen Deprivation

Insufficient oxygen supply and blood flow in utero and during birth is associated with increased risk for ADHD in later life.

Birth asphyxia is associated with a 26% greater risk of developing ADHD, while neonatal respiratory distress syndrome is associated with a 47% greater risk for ADHD, according to a 2012 study of more than 13,500 children with ADHD.¹⁵

C-Section Delivery

Compared to babies born via vaginal delivery, babies born via cesarean delivery (whether elective or emergency) are at greater risk for ADHD, according to a 2019 review of 61 studies comprising more than 20 million deliveries.¹⁶ The link between the two – including whether C-section delivery plays a causal role in the development of ADHD – remains unknown.

Prematurity and Low Birth Weight

Low birth weight and prematurity do appear to have a significant causal influence on the development of ADHD. Extremely preterm babies and those with very low birth weight are about three times likelier than healthy babies to develop ADHD, according to a 2018 meta-analysis of 12 studies involving 1,787 participants.¹⁷ Studies that controlled for genetics found the association still held.

ADHD Risk Factors: Events and Exposures in Early Life

Lead and Other Pollutants

Research on lead as a developmental neurotoxicant is robust. Its correlation with ADHD is also well established.¹⁸ Even low levels of exposure have an effect on ADHD.

Recent evidence suggests that lead has a causal role in ADHD. In our 2016 study, we looked at the effect of a common gene mutation – HFE C282Y – on the relationship between blood lead levels and ADHD symptoms in children, and found that children with ADHD who had the gene mutation exhibited greater symptoms of hyperactivity and impulsivity than did children with ADHD without the mutation.¹⁹

Because the C282Y gene helps to control the effects of lead in the body, and the mutation was spread randomly in the children, it is difficult to explain these findings unless lead is, in fact, part of the cause of ADHD, not just associated with it. Numerous animal studies also support a link.

As far as other pollutants, early exposure to nitrous dioxide and persistent organic pollutants has also been linked to ADHD, among others.^{20 21}

Breastfeeding and ADHD

Breastfeeding is linked to decreased risk for ADHD in children.²² Mothers of children with ADHD are more likely than mothers of neurotypical children to report shorter breastfeeding duration.²³ What underlies the ADHD-breastfeeding link is unclear, like whether breastfeeding protects the developing brain from ADHD, or if infants who are going to develop ADHD are more difficult to breastfeed and are thus breastfed for a shorter period of time. We used advanced statistical methods to test this in one study, and found that the causality was reversed: child ADHD caused reduced breastfeeding duration.

Head Injuries

Head injuries, especially severe traumatic brain injuries, increase risk for ADHD, according to a 2021 review of 24 studies that included 12,374 children.²⁴

Head injuries and ADHD share a complicated chicken-and-egg relationship, as ADHD itself increases risk for head trauma.²⁵ Children with ADHD are twice or three times as likely to obtain serious head injuries and accidental head injuries through their impulsivity.

Childhood Trauma

Children who experience trauma and who are exposed to adverse childhood experiences (ACES) are at increased risk for ADHD. The inverse is also true: ADHD increases the risk of exposure to trauma.^{26 27}

Trauma is also known to exacerbate symptoms of ADHD. Compared to children without ADHD, children with ADHD who experience trauma are more reactive and sensitive to it, and need additional support.

Beyond a bi-directional relationship, trauma and ADHD share similar symptoms. It takes an experienced clinician to distinguish the conditions and understand if a child is experiencing a trauma effect or showing true signs of ADHD or both.

ADHD Risk Factors: The Bottom Line

Though research links a host of prenatal and early life risk factors to ADHD, it’s crucial to understand the following:

1. Few of these risk factors are yet known to be causal.

In most instances, we don’t yet know if risk factors have a causal effect or if it’s just artificial due to unmeasured correlates (in particular, genetic confounding). A key principle seems to be that the accumulation of multiple risk factors matters most in a child’s health. Genetic risk can be seen as one of the risk factors. But even a family history of ADHD doesn’t guarantee that a child will develop the condition.

2. Not all ADHD risk factors have equal influence.

Evidence for risk factors vary from “very strong” to “maybe.” Risk factors also tend to add up and occur in clusters, which ultimately makes it difficult to assess a factor’s relationship to ADHD. Some populations, including disadvantaged groups, may also be more vulnerable and sensitive to these risk factors or experience more of them.

3. To date, research has focused almost entirely on ADHD risk factors related to maternal health and pregnancy – but a dramatic shift is underway.

The history of psychiatry has unfortunately seen misguided blaming of mothers. It is important to realize that many of the risks are unavoidable, and that fathers are not off the hook. Paternal support, for one, can be a protective factor in maternal prenatal health and thus fetal health. But we are also learning more about how paternal exposures pre-pregnancy can affect sperm health and thus fetal health.

4. Exposure to a risk factor – even to a causal contributor of ADHD – does not guarantee an ADHD diagnosis down the line.

Most children who are exposed to these risk factors do not develop ADHD. There still has to be some other vulnerability or some other factors combined with these things in order for ADHD to emerge. In all, exposure to risk factors are rarely by themselves the entire explanation.

ADHD Risk Factors: What Parents Can Do

Exposure to ADHD risk factors may become a source of regret and second-guessing for parents. What I say to caregivers in this: Move forward; don’t belabor the past. Ultimately, at today’s level of knowledge, the cause of your child’s ADHD is not entirely known. More practical is to recognize that there is still a lot you can do to move forward positively.

If you are an expectant parent and/or the parent of a child with ADHD, follow these strategies below to minimize exposures, manage (and even reduce) your child’s ADHD symptoms, and protect your family’s health and wellbeing.

1. Engage in Behavioral Parent Training

ADHD can cause challenging behaviors that may overwhelm parents and lead to a negative parent-child dynamic — in itself a factor that can impact a child’s health and wellbeing. That’s why behavioral parent training (BPT) is an essential component of any child’s ADHD treatment. BPT teaches you how to respond to your child’s behaviors without inadvertently making those behaviors worse. Another benefit of BPT? It increases the chances that ADHD medication will work, and can lead to medication working at a lower dose.

2. Focus on Nutrition

Research has uncovered various links between nutrition and ADHD – some of which translate to actionable steps for your family.

• Eat healthy foods during pregnancy. A 2018 study of about 1,240 mother-child pairs found that children whose mothers had a healthy prenatal diet were less likely to exhibit symptoms of hyperactivity over time than were children whose mothers had an unhealthy prenatal diet.²⁸ Limit heavily processed foods and opt for whole, nutrient-dense foods.
• Consider omega-3 supplements (1000 mg EHA/DPA a day). Children with ADHD tend to have lower omega-3 levels compared to children without ADHD, and supplementation modestly improves ADHD symptoms.²⁹ Furthermore, prenatal omega-3 supplementation improved attention development in infants and toddlers in at least one controlled experiment.³⁰
• Try an elimination diet. Five percent to twenty-five percent of children with ADHD may see symptom improvement in response to a diet that eliminates common food allergens (cow-milk protein, soy, wheat, eggs, peanuts, seafood/shellfish) and additives (artificial food dyes and flavors).³¹ An elimination diet may be worthwhile if you suspect a dietary factor at play. But note that dietary changes are often difficult to implement. Your child may object, or the entire family may need to be involved. Adequate nutritional replacement also must be identified. Thus, only attempt this elimination plan in consultation with a behavioral counselor and nutritionist and/or your child’s pediatrician.
• Opt for whole, unprocessed foods. Shop the perimeter of the supermarket for fresh, nutrient-dense foods. Avoid added sugars and caffeine, and try to keep your kitchen stocked with only healthy food choices.
• Test for nutritional deficiencies. Children with ADHD are more likely than other children to have low levels of iron, zinc, and vitamin D.^{32 33 34} Supplementation can sometimes help with ADHD if nutrient levels are low. Recent evidence also suggests that specialized multi-nutrient supplements benefit important aspects of ADHD.³⁵

3. Encourage Good Sleep Habits

Behaviorally-related sleep problems — from going to bed to falling and staying asleep — are common among children with ADHD. (True endogenous sleep disorders also occur at above chance levels in ADHD, but still are present only in a minority.³⁶ ) Insufficient sleep, of course, worsens ADHD symptoms and functioning.

Create a bedtime routine, turn off or take away electronic devices before bed, and aim for your child to get 10 hours of sleep per night (depending on age). Talk to your child’s doctor to screen for potential co-occurring sleep disorders, or to get help with your child’s sleep problems.

4. Get Your Child Moving

Exercise improves health, mood, and ADHD symptoms.³⁷ Exercise may even reverse some of the biological effects of past traumatic events on the body, as shown in animal studies.³⁸ Children need at least one hour of moderate to vigorous exercise — be it sports, free play, or anything in between — on most days of the week.³⁹

Nutrition, sleep, and exercise are healthy lifestyle factors with the clearest effect on ADHD symptoms. While they usually will not substitute for professional treatment, they may well reduce the stimulant or psychotherapeutic dosage your child needs.

5. Reduce Exposure to Lead and Other Pollutants

A lead test —for your child and for yourself, especially if you are pregnant or planning for it — is worth doing if you live in an area of high lead exposure. However, note that common medical lead tests do not detect the low exposure levels that have now been associated with ADHD in scientific studies. Thus, even if your child does not have detectable exposure, it is prudent to minimize lead exposure.

A healthy diet and sufficient levels of iron and vitamin D can help minimize the effects of lead (because of the way lead is metabolized).

Consider the following steps to address potential pollutant exposures at home and school:

• Purchase a lead-removing water filter certified by an ANSI-accredited body.
• Install HEPA-quality air filters.
• If you live in home built before 1980, prevent and repair loose or chipped paint and do not let your child play in the soil right next to the house if possible.
• Learn about various sources of lead exposure and how to protect your family.

6. Limit Screen Time and Watch for Quality

Though still a new area of research, findings from screen time research are cautionary. In a 2018 study, teens who spent excessive time on social media were more likely to exhibit ADHD symptoms after a two-year follow-up compared to teens who did not use social media as frequently.⁴⁰

“Gaming addiction,” while still controversial, is receiving increased scrutiny. While more work is forthcoming, it remains possible that children with ADHD may be more susceptible to problematic video game play due to self-regulation challenges and the high-reward nature of gaming itself. Studies also link exposure to violent content with increased aggression in vulnerable children.⁴¹

7. Practice Self-Care

• Manage stress and reduce stressors in your life. The more stressed out you are, the more stressed out your child will be, and the more you’ll get into a negative cycle. Social support and self-compassion are among the key elements for managing stress.
• Recognize your own history of stress and trauma if present, and seek counseling and treatment if needed. Tell your doctor (and your child’s doctor) about your family’s experience with trauma, if any.
• Eat a healthy diet, practice good sleep hygiene, and get exercise daily.
• If you have ADHD, depression, or other mental health challenge yourself, stick to your treatment plan or talk to your doctor to see if an adjustment is necessary.

What Causes ADHD? Next Steps

• Read: Epigenetics and ADHD — How Environment and Lifestyle Impact ADHD
• Read: Beyond Genes  — Leveraging Sleep, Exercise, and Nutrition to Improve ADHD
• Free Download: Natural ADHD Treatment Options
• Resource Hub: What Causes ADHD?

The content for this article was derived, in part, from the ADDitude ADHD Experts webinar titled, “Genes and the Environment: How Biology and Exposures Contribute to ADHD in Children” [Video Replay & Podcast #433] with Joel Nigg, Ph.D., which was broadcast on November 30, 2022.

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Sources

¹ Han, J. Y., Kwon, H. J., Ha, M., Paik, K. C., Lim, M. H., Gyu Lee, S., Yoo, S. J., & Kim, E. J. (2015). The effects of prenatal exposure to alcohol and environmental tobacco smoke on risk for ADHD: a large population-based study. Psychiatry Research, 225(1-2), 164–168. https://doi.org/10.1016/j.psychres.2014.11.009

² Garrison-Desany, H. M., Hong, X., Maher, B. S., Beaty, T. H., Wang, G., Pearson, C., Liang, L., Wang, X., & Ladd-Acosta, C. (2022). Individual and combined association between prenatal polysubstance exposure and childhood risk of attention-deficit/hyperactivity disorder. JAMA Network Open, 5(3), e221957. https://doi.org/10.1001/jamanetworkopen.2022.1957

³ Eilertsen, E. M., Gjerde, L. C., Reichborn-Kjennerud, T., Ørstavik, R. E., Knudsen, G. P., Stoltenberg, C., Czajkowski, N., Røysamb, E., Kendler, K. S., & Ystrom, E. (2017). Maternal alcohol use during pregnancy and offspring attention-deficit hyperactivity disorder (ADHD): a prospective sibling control study. International Journal of Epidemiology, 46(5), 1633–1640. https://doi.org/10.1093/ije/dyx067

⁴ Centers for Disease Control and Prevention. Fetal Alcohol Spectrum Disorders (FASDs) – Basics. https://www.cdc.gov/ncbddd/fasd/facts.html

⁵ Chasnoff, I. J., Wells, A. M., & King, L. (2015). Misdiagnosis and missed diagnoses in foster and adopted children with prenatal alcohol exposure. Pediatrics, 135(2), 264–270. https://doi.org/10.1542/peds.2014-2171

⁶ Luderer, M., Ramos Quiroga, J. A., Faraone, S. V., Zhang James, Y., & Reif, A. (2021). Alcohol use disorders and ADHD. Neuroscience and biobehavioral reviews, 128, 648–660. https://doi.org/10.1016/j.neubiorev.2021.07.010

⁷ He, Y., Chen, J., Zhu, L. H., Hua, L. L., & Ke, F. F. (2020). Maternal Smoking During Pregnancy and ADHD: Results From a Systematic Review and Meta-Analysis of Prospective Cohort Studies. Journal of Attention Disorders, 24(12), 1637–1647. https://doi.org/10.1177/1087054717696766

⁸ Zhu, J. L., Olsen, J., Liew, Z., Li, J., Niclasen, J., & Obel, C. (2014). Parental smoking during pregnancy and ADHD in children: the Danish national birth cohort. Pediatrics, 134(2), e382–e388. https://doi.org/10.1542/peds.2014-0213

⁹ Biederman, J., Fitzgerald, M., Spencer, T. J., Bhide, P. G., McCarthy, D. M., Woodworth, K. Y., Saunders, A., & Faraone, S. V. (2020). Is Paternal Smoking at Conception a Risk for ADHD? A Controlled Study in Youth With and Without ADHD. Journal of attention disorders, 24(11), 1493–1496. https://doi.org/10.1177/1087054717690809

¹⁰ Ji, Y., Azuine, R. E., Zhang, Y., Hou, W., Hong, X., Wang, G., Riley, A., Pearson, C., Zuckerman, B., & Wang, X. (2020). Association of cord plasma biomarkers of in utero acetaminophen exposure with risk of attention-deficit/hyperactivity disorder and autism spectrum disorder in childhood. JAMA Psychiatry, 77(2), 180–189. https://doi.org/10.1001/jamapsychiatry.2019.3259

¹¹ U.S. Food and Drug Administration. FDA drug safety communication: FDA has reviewed possible risks of pain medicine use during pregnancy. Retrieved from https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-fda-has-reviewed-possible-risks-pain-medicine-use-during-pregnancy

¹² Edlow AG. Maternal Metabolic Disease and Offspring Neurodevelopment—An Evolving Public Health Crisis. JAMA Netw Open. 2021;4(10):e2129674. doi:10.1001/jamanetworkopen.2021.29674

¹³ Perea, V., Simó-Servat, A., Quirós, C., Alonso-Carril, N., Valverde, M., Urquizu, X., Amor, A. J., López, E., & Barahona, M. J. (2022). Role of Excessive Weight Gain During Gestation in the Risk of ADHD in Offspring of Women With Gestational Diabetes. The Journal of Clinical Endocrinology and Metabolism, 107(10), e4203–e4211. https://doi.org/10.1210/clinem/dgac483

¹⁴ MacKinnon, N., Kingsbury, M., Mahedy, L., Evans, J., & Colman, I. (2018). The Association Between Prenatal Stress and Externalizing Symptoms in Childhood: Evidence From the Avon Longitudinal Study of Parents and Children. Biological psychiatry, 83(2), 100–108. https://doi.org/10.1016/j.biopsych.2017.07.010

¹⁵ Getahun, D., Rhoads, G. G., Demissie, K., Lu, S. E., Quinn, V. P., Fassett, M. J., Wing, D. A., & Jacobsen, S. J. (2013). In utero exposure to ischemic-hypoxic conditions and attention-deficit/hyperactivity disorder. Pediatrics, 131(1), e53–e61. https://doi.org/10.1542/peds.2012-1298

¹⁶ Zhang, T., Sidorchuk, A., Sevilla-Cermeño, L., Vilaplana-Pérez, A., Chang, Z., Larsson, H., Mataix-Cols, D., & Fernández de la Cruz, L. (2019). Association of cesarean delivery with risk of neurodevelopmental and psychiatric disorders in the offspring: A systematic review and meta-analysis. JAMA Network Open, 2(8), e1910236. https://doi.org/10.1001/jamanetworkopen.2019.10236

¹⁷ Franz, A. P., Bolat, G. U., Bolat, H., Matijasevich, A., Santos, I. S., Silveira, R. C., Procianoy, R. S., Rohde, L. A., & Moreira-Maia, C. R. (2018). Attention-Deficit/Hyperactivity Disorder and Very Preterm/Very Low Birth Weight: A Meta-analysis. Pediatrics, 141(1), e20171645. https://doi.org/10.1542/peds.2017-1645

¹⁸ Nigg, J. T., Knottnerus, G. M., Martel, M. M., Nikolas, M., Cavanagh, K., Karmaus, W., & Rappley, M. D. (2008). Low blood lead levels associated with clinically diagnosed attention-deficit/hyperactivity disorder and mediated by weak cognitive control. Biological psychiatry, 63(3), 325–331. https://doi.org/10.1016/j.biopsych.2007.07.013

¹⁹ Nigg, J. T., Elmore, A. L., Natarajan, N., Friderici, K. H., & Nikolas, M. A. (2016). Variation in an Iron Metabolism Gene Moderates the Association Between Blood Lead Levels and Attention-Deficit/Hyperactivity Disorder in Children. Psychological science, 27(2), 257–269. https://doi.org/10.1177/0956797615618365

²⁰ Thygesen, M., Holst, G. J., Hansen, B., Geels, C., Kalkbrenner, A., Schendel, D., Brandt, J., Pedersen, C. B., & Dalsgaard, S. (2020). Exposure to air pollution in early childhood and the association with Attention-Deficit Hyperactivity Disorder. Environmental Research, 183, 108930. https://doi.org/10.1016/j.envres.2019.108930

²¹ Lenters, V., Iszatt, N., Forns, J., Čechová, E., Kočan, A., Legler, J., Leonards, P., Stigum, H., & Eggesbø, M. (2019). Early-life exposure to persistent organic pollutants (OCPs, PBDEs, PCBs, PFASs) and attention-deficit/hyperactivity disorder: A multi-pollutant analysis of a Norwegian birth cohort. Environment international, 125, 33–42. https://doi.org/10.1016/j.envint.2019.01.020

²² Soled, D., Keim, S. A., Rapoport, E., Rosen, L., & Adesman, A. (2021). Breastfeeding Is Associated with a Reduced Risk of Attention-Deficit/Hyperactivity Disorder Among Preschool Children. Journal of developmental and behavioral pediatrics : JDBP, 42(1), 9–15. https://doi.org/10.1097/DBP.0000000000000854

²³ Stadler, D. D., Musser, E. D., Holton, K. F., Shannon, J., & Nigg, J. T. (2016). Recalled Initiation and Duration of Maternal Breastfeeding Among Children with and Without ADHD in a Well Characterized Case-Control Sample. Journal of abnormal child psychology, 44(2), 347–355. https://doi.org/10.1007/s10802-015-9987-9

²⁴ Asarnow, R. F., Newman, N., Weiss, R. E., & Su, E. (2021). Association of Attention-Deficit/Hyperactivity Disorder Diagnoses With Pediatric Traumatic Brain Injury: A Meta-analysis. JAMA Pediatrics, 175(10), 1009–1016. https://doi.org/10.1001/jamapediatrics.2021.2033

²⁵ Liou, Y. J., Wei, H. T., Chen, M. H., Hsu, J. W., Huang, K. L., Bai, Y. M., Su, T. P., Li, C. T., Yang, A. C., Tsai, S. J., Lin, W. C., & Chen, T. J. (2018). Risk of Traumatic Brain Injury Among Children, Adolescents, and Young Adults With Attention-Deficit Hyperactivity Disorder in Taiwan. The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 63(2), 233–238. https://doi.org/10.1016/j.jadohealth.2018.02.012

²⁶ Brown, N. M., Brown, S. N., Briggs, R. D., Germán, M., Belamarich, P. F., & Oyeku, S. O. (2017). Associations Between Adverse Childhood Experiences and ADHD Diagnosis and Severity. Academic pediatrics, 17(4), 349–355. https://doi.org/10.1016/j.acap.2016.08.013

²⁷ Lugo-Candelas, C., Corbeil, T., Wall, M., Posner, J., Bird, H., Canino, G., Fisher, P. W., Suglia, S. F., & Duarte, C. S. (2021). ADHD and risk for subsequent adverse childhood experiences: understanding the cycle of adversity. Journal of child psychology and psychiatry, and allied disciplines, 62(8), 971–978. https://doi.org/10.1111/jcpp.13352

²⁸ Galera, C., Heude, B., Forhan, A., Bernard, J. Y., Peyre, H., Van der Waerden, J., Pryor, L., Bouvard, M. P., Melchior, M., Lioret, S., de Lauzon-Guillain, B., & EDEN Mother-Child Cohort Study Group (2018). Prenatal diet and children’s trajectories of hyperactivity-inattention and conduct problems from 3 to 8 years: the EDEN mother-child cohort. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 59(9), 1003–1011. https://doi.org/10.1111/jcpp.12898

²⁹ Hawkey, E., & Nigg, J. T. (2014). Omega-3 fatty acid and ADHD: blood level analysis and meta-analytic extension of supplementation trials. Clinical psychology review, 34(6), 496–505. https://doi.org/10.1016/j.cpr.2014.05.005

³⁰ Colombo, J., Kannass, K. N., Shaddy, D. J., Kundurthi, S., Maikranz, J. M., Anderson, C. J., Blaga, O. M., & Carlson, S. E. (2004). Maternal DHA and the development of attention in infancy and toddlerhood. Child development, 75(4), 1254–1267. https://doi.org/10.1111/j.1467-8624.2004.00737.x

³¹ Nigg, J. T., & Holton, K. (2014). Restriction and elimination diets in ADHD treatment. Child and adolescent psychiatric clinics of North America, 23(4), 937–953. https://doi.org/10.1016/j.chc.2014.05.010

³² Tseng, P. T., Cheng, Y. S., Yen, C. F., Chen, Y. W., Stubbs, B., Whiteley, P., Carvalho, A. F., Li, D. J., Chen, T. Y., Yang, W. C., Tang, C. H., Chu, C. S., Yang, W. C., Liang, H. Y., Wu, C. K., & Lin, P. Y. (2018). Peripheral iron levels in children with attention-deficit hyperactivity disorder: a systematic review and meta-analysis. Scientific reports, 8(1), 788. https://doi.org/10.1038/s41598-017-19096-x

³² Arnold, L. E., & DiSilvestro, R. A. (2005). Zinc in attention-deficit/hyperactivity disorder. Journal of Child and Adolescent Psychopharmacology, 15(4), 619–627. https://doi.org/10.1089/cap.2005.15.619

³⁴ Li, H. H., Yue, X. J., Wang, C. X., Feng, J. Y., Wang, B., & Jia, F. Y. (2020). Serum Levels of Vitamin A and Vitamin D and Their Association With Symptoms in Children With Attention Deficit Hyperactivity Disorder. Frontiers in psychiatry, 11, 599958. https://doi.org/10.3389/fpsyt.2020.599958

³⁵ Johnstone, J. M., Hatsu, I., Tost, G., Srikanth, P., Eiterman, L. P., Bruton, A. M., Ast, H. K., Robinette, L. M., Stern, M. M., Millington, E. G., Gracious, B. L., Hughes, A. J., Leung, B. M. Y., & Arnold, L. E. (2022). Micronutrients for Attention-Deficit/Hyperactivity Disorder in Youths: A Placebo-Controlled Randomized Clinical Trial. Journal of the American Academy of Child and Adolescent Psychiatry, 61(5), 647–661. https://doi.org/10.1016/j.jaac.2021.07.005

³⁶ Hvolby A. (2015). Associations of sleep disturbance with ADHD: implications for treatment. Attention deficit and hyperactivity disorders, 7(1), 1–18. https://doi.org/10.1007/s12402-014-0151-0

³⁷ Seiffer, B., Hautzinger, M., Ulrich, R., & Wolf, S. (2022). The Efficacy of Physical Activity for Children with Attention Deficit Hyperactivity Disorder: A Meta-Analysis of Randomized Controlled Trials. Journal of attention disorders, 26(5), 656–673. https://doi.org/10.1177/10870547211017982

³⁸ Kashimoto, R. K., Toffoli, L. V., Manfredo, M. H. F., Volpini, V. L., Martins-Pinge, M. C., Pelosi, G. G., & Gomes, M. V. (2016). Physical exercise affects the epigenetic programming of rat brain and modulates the adaptive response evoked by repeated restraint stress. Behavioural brain research, 296, 286–289. https://doi.org/10.1016/j.bbr.2015.08.038

³⁹ Lobelo, F., Muth, N. D., Hanson, S., Nemeth, B. A., COUNCIL ON SPORTS MEDICINE AND FITNESS, & SECTION ON OBESITY (2020). Physical Activity Assessment and Counseling in Pediatric Clinical Settings. Pediatrics, 145(3), e20193992. https://doi.org/10.1542/peds.2019-3992

⁴⁰ Ra, C. K., Cho, J., Stone, M. D., De La Cerda, J., Goldenson, N. I., Moroney, E., Tung, I., Lee, S. S., & Leventhal, A. M. (2018). Association of Digital Media Use With Subsequent Symptoms of Attention-Deficit/Hyperactivity Disorder Among Adolescents. JAMA, 320(3), 255–263. https://doi.org/10.1001/jama.2018.8931

⁴¹ Anderson, C. A., Bushman, B. J., Bartholow, B. D., Cantor, J., Christakis, D., Coyne, S. M., Donnerstein, E., Brockmyer, J. F., Gentile, D. A., Green, C. S., Huesmann, R., Hummer, T., Krahé, B., Strasburger, V. C., Warburton, W., Wilson, B. J., & Ybarra, M. (2017). Screen Violence and Youth Behavior. Pediatrics, 140(Suppl 2), S142–S147. https://doi.org/10.1542/peds.2016-1758T

Researchers have “refined the genetic architecture of ADHD” after identifying 27 variations in genetic code that are most present in people with the attention deficit hyperactivity disorder. A Danish-led international genome-wide association study (GWAS) published in Nature highlighted these and 76 probable risk genes — including “brain-expressed genes” involved in development and genes known to influence other psychiatric disorders. ¹

The study identified 27 ADHD risk loci, or locations of a gene or mutation on a chromosome. Researchers then linked these loci to 76 ADHD risk genes. They found that many of the genes thought to influence ADHD also influence early embryonic brain development.

“This emphasizes that ADHD should be seen as a brain developmental disorder, and that [ADHD] is most likely influenced by genes that have a major impact on the brain’s early development,” said Ditte Demontis, one of the study’s authors and a professor at Aarhus University.

Researchers estimated that up to 7,300 common genetic variants influence ADHD, highlighting its polygenicity. They observed that common variants were often found in genes expressed in the frontal cortex, which is responsible for attention and working memory, and in genes expressed in midbrain dopaminergic neurons that control voluntary movement and reward processing.

“There was a time about 30 years ago when many scientists — and the general public — thought that… we would find the [one] gene for ADHD, bipolar disorder, autism, and so on,” said Joel Nigg, Ph.D., in a recent ADDitude webinar. “That is clearly wrong. We now know after 25 to 30 years of extensive genetic research that lots of genes are involved in these conditions; there’s lots of overlap and genetic correlations. And [we know] that genes don’t explain the whole story for any of these conditions, despite some fairly substantial genetic influence in all of them.”

According to the study, 84% to 98% of common variants tied to ADHD seemed to influence other psychiatric disorders including autism spectrum disorder, depression, and schizophrenia. This correlates with the high rate of comorbidity seen among ADHD patients.

“As many as 80% of adults with ADHD have at least one co-existing psychiatric disorder, while approximately 60% of children with ADHD have at least one co-occurring condition,” wrote Theresa Cerulli, M.D., in an ADDitude article about complex ADHD.

The considerable genetic overlap found in the current study helps to explain the frequency of ADHD comorbidities.

“The presence of co-occurring conditions almost always muddles the diagnosis, treatment, and prognosis of ADHD,” Cerulli wrote. “ADHD and comorbidities may also influence the presentation and severity of one another, which can complicate the detection and treatment of symptoms.

This GWAS meta-analysis of ADHD is the largest to date. Researchers analyzed twice as many ADHD cases and identified more than double the number of ADHD-associated loci compared to a 2019 GWAS. ² That study helped establish the role of common variants in ADHD; the current study is an updated GWAS meta-analysis.

“The results advance our understanding of the underlying biology of ADHD and reveal new aspects of the polygenic architecture of ADHD, its relationship with other phenotypes and its impact on cognitive domains,” wrote the researchers.

The study sampled 186,843 people with ADHD, 38,691 controls, and analyzed data on over 6 million variants.

Sources

¹Demontis, D., Walters, G. B., Athanasiadis, G., Walters, R., Therrien, K., Nielsen, T. T., … Børglum, A. D. (2023). Genome-wide analyses of ADHD identify 27 risk loci, refine the genetic architecture and implicate several cognitive domains. Nature Genetics, 55(2), 198–208. doi: 10.1038/s41588-022-01285-8

²  Demontis, D., Walters, R.K., Martin, J. et al. (2019). Discovery of the first genome-wide significant risk loci for attention deficit/hyperactivity disorder. Nat Genet 51, 63–75. https://doi.org/10.1038/s41588-018-0269-7

• Improved diet, exercise, or sleep: 11.9%
• Education services (e.g., tutoring, accommodations): 10.13%
• Behavioral therapy: 7.34%
• Limited screen time: 4.56%
• Supplements (e.g., omega-3s, magnesium, zinc): 2.53%
• Speech, occupational, or physical therapy: 2.53%
• Mindfulness exercises: 1.77%

Comments and questions submitted during the webinar, titled “Genes and the Environment: How Biology and Exposures Contribute to ADHD in Children,” centered on the lifestyle and environmental factors with the biggest impact on ADHD symptoms.

The Importance of Diet, Exercise, and Sleep in Managing ADHD

Diet, exercise, and sleep are the Big Three — the lifestyle changes with the most significant, most scientifically proven effect on ADHD. When these lifestyle factors are optimized, your child may require a lower dose of stimulant medication or may find their ADHD medication works better, according to Joel Nigg, Ph.D., a clinical psychologist and a professor in the departments of psychiatry and behavioral sciences at Oregon Health & Science University.

Next Steps to Optimize Diet, Exercise, and Sleep:

• Read: Exercise and Sleep – the Better Brain Therapies Your Child Needs
• Read: 5 Big Natural Remedies for ADHD
• Read: Leveraging Sleep, Exercise, and Nutrition to Improve ADHD

Q: “Are there specific foods or nutrients that we should increase to better manage ADHD symptoms?”

Omega-3 supplements have been shown to improve ADHD symptoms. Learn more about the benefits of omega-3s in these resources:

• Read: Omega 3s – the Ultimate (ADHD) Brain Food
• Free Download: 12 Surprising Sources of Omega-3 Fatty Acids
• Read: “How Do I Get My Sensory-Sensitive Child to Take Fish Oil Supplements?”

Q: “What, if anything, should we eliminate from our child’s diet?”

A portion of children with ADHD will respond positively to a diet that eliminates allergens, additives, and dyes. Consult with your child’s doctor and/or a nutritionist to safely follow an elimination diet.

Next Steps:

• Read: The Truth About Food Dyes and ADHD – What Science Tells Us
• Read: Eggs, Dairy, Nuts, and Soy – Testing for Food Sensitivities with an ADHD Elimination Diet
• Free Download: What to Eat — And Avoid — to Improve ADHD Symptoms

Q: “What about caffeine?”

The active ingredients in caffeine are clearly beneficial for attention, Nigg says, but it’s unknown what caffeine doses are safe for children. Too much caffeine can actually be harmful for development. It’s best to avoid caffeine (e.g., watch sports drinks and other sources of caffeine) until the late teenage years.

Next Steps:

• Read: The Truth About Caffeine and ADHD

Screen Time and Video Games

Q: “Do violent video games impact my child’s behavior?”

“There is quite a bit of evidence linking violent content with increased aggression in vulnerable children,” Nigg says. Monitor your child’s gaming activities and redirect if you notice signs of aggression, depression, and irritability.

Next Steps:

• Read: ADHD and Video Games – Is Your Child Hooked?
• Read: Do Video Games Exacerbate ADHD?
• Free Download: An “Ethics Manual” for Your Child’s Electronics

Stress and Family Conflict

Q: “My child’s ADHD has worsened since the pandemic. Do I need to adjust their treatment plan?”

“Scientific evidence supports your feeling that kids’ problems have gotten a lot worse in the last two and a half, three years,” Nigg says. In a chronically stressful situation, it’s normal for children to be (and act) stressed. As the stressful situation reduces, your child’s behaviors should go back to baseline. In the meantime, continue to support and coach your child and model appropriate coping behaviors. Talk to your child’s doctor if you notice concerning behaviors. There could be more than ADHD in the picture, which will influence your child’s course of treatment.

Next Steps:

• Read: How Do You Reassure Your Anxious Child When You’re Scared, Too?
• Read: How Trauma and Chronic Stress Affect Developing Brains
• Read: Does Trauma Cause ADHD? And Vice Versa?
• Read: Building Resilience Begins Here –  6 Motivation Strategies for ADHD Families

Remember, ADHD is Not Caused by “Bad Parenting”

Parents of children with ADHD can easily get caught in negative loops that may inadvertently reinforce challenging behaviors. (Parental ADHD can also complicate the dynamic.) Behavioral therapy is proven to help reduce difficult behaviors in children and create a positive family dynamic. Parental self-care is also important.

Next Steps:

• Read: Behavioral Therapy for ADHD – A Pragmatic Parent’s Guide
• Read: “None of Us Were Trained How to Be Good Parents” – An ADHD Guide to Behavior Therapy
• Read: A Survival Guide for Parents with ADHD – Strategies from Preschool to High School
• Read: Hey, ADHD Parents – Shoot for Progress, not Perfection
  

To learn more about how lifestyle and environmental factors impact ADHD symptoms in children, listen to the ADDitude ADHD Experts webinar, “Genes and the Environment: How Biology and Exposures Contribute to ADHD in Children” by Joel Nigg, Ph.D., which was broadcast live on November 30, 2022.

How to Treat ADHD in Children: Next Questions

1. What ADHD medications are used to treat children?
2. Is ADHD medication right for my child?
3. What are common side effects associated with ADHD medication?
4. What natural treatments help kids with ADHD?
   • What are the most effective natural ADHD treatments for kids?
   • What foods can help control ADHD symptoms?
   • What vitamins and supplements should my child take?
   • Does brain training help with ADHD?
   • How much and what type of exercise helps kids with ADHD?
   • What types of therapy help patients with ADHD?
5. What if the medication stops working?
6. How can I find an ADHD specialist near me?

SUPPORT ADDITUDE
Thank you for reading ADDitude. To support our mission of providing ADHD education and support, please consider subscribing. Your readership and support help make our content and outreach possible. Thank you.

ADHD brains exhibit unique differences in the expression of genes used to code neurotransmitters, the chemical messengers that power attention and communication, among other brain functions. This is the finding of a new study conducted by researchers at the National Institute of Health (NIH) that uncovered a key difference in gene activity in the brains of individuals diagnosed with attention deficit hyperactivity disorder (ADHD).¹

The study, led by scientists at the NIH’s National Human Genome Research Institute (NHGRI) and published in Molecular Psychiatry, shed light on the ways in which genomic differences may contribute to ADHD symptoms.

Using postmortem brain tissue for the first time to investigate ADHD, researchers gathered gene-level information to explore the influence of genes on cell function and symptoms. Investigating gene expression through RNA sequencing, the scientists studied the caudate and frontal cortex of the brain, two connected regions that are crucial in attentional control and management. Differences in the activity and structure of these regions of the brain in individuals with ADHD have been established through previous research.

Gustavo Sudre, Ph.D., associate investigator in the Social and Behavioral Research Branch in NHGRI’s Intramural Research Program, who led this study, noted that multiple studies point toward the expression of the same genes in individuals with ADHD and other neurological conditions. “Interestingly, these gene-expression differences were similar to those seen in other conditions,” he said. “Which may reflect differences in how the brain functions, such as in autism.”

The study marks an important advancement in ADHD research. While past studies have successfully identified genes associated with ADHD, they have not previously studied how genomic differences contribute to symptoms. “This allows us to inch closer to understanding how genomic differences alter gene expression in the brain and contribute to ADHD symptoms,” said Philip Shaw, M.D., Ph.D., senior investigator in the Social and Behavioral Research Branch at NHGRI, who supervised the study.

Shaw also pointed out the value of conducting research on postmortem brain tissue, which can be difficult to access due to limited donations. “Such postmortem studies have accelerated our understanding of other mental health challenges,” he said, “but to date no such studies have looked at ADHD until now.”

Sources

¹Sudre, G., Gildea, D.E., Shastri, G.G. et al. Mapping the cortico-striatal transcriptome in attention deficit hyperactivity disorder. Mol Psychiatry (2022). ¹ https://doi.org/10.1038/s41380-022-01844-9

ADHD may be hereditary, but emerging research suggests environmental factors and experiences can affect a child’s development and behavior in ways that may last a lifetime —or may be reversible. We know that exposure to stress, adversity, and trauma as well as many other environmental exposures, affect how genes are influenced, or expressed. We also know that these environmental factors can affect the developing brain and make learning and behavior challenges associated with ADHD worse during the early and middle years of childhood.

These findings provide clues to maximize children’s health from before birth into childhood. Among the clues: certain lifestyle changes can slow or reverse the harm caused by stress and other toxic influences — and help to restore healthy development in children with ADHD.

In this webinar, you will learn:

• How genetics influence ADHD
• About the environmental risk factors related to brain development and ADHD
• About the behavioral and learning challenges in children with ADHD that result from adverse environmental conditions
• How emerging research into environmental influences on a child’s brain development may inform prevention or new treatment
• How exercise, stress management, and lifestyle changes can benefit a child’s development and attention

Watch the Video Replay

Enter your email address in the box above labeled “Video Replay + Slide Access” to watch the video replay (closed captions available) and download the slide presentation.

Download or Stream the Podcast Audio

Click the play button below to listen to this episode directly in your browser, click the symbol to download to listen later, or open in your podcasts app: Apple Podcasts; Google Podcasts; Stitcher; Spotify; Amazon Music; iHeartRADIO.

More on Genes, the Environment, and ADHD

• Download: Unraveling the Mysteries of Your ADHD Brain
• Read: How Environment, Lifestyle, and Stress Impact ADHD
• Read: Are Everyday Toxins Causing ADHD?

Obtain a Certificate of Attendance

If you attended the live webinar on November 30, 2022, watched the video replay, or listened to the podcast, you may purchase a certificate of attendance option (cost: $10). Note: ADDitude does not offer CEU credits. Click here to purchase the certificate of attendance option »

Meet the Expert Speaker:

Joel Nigg, Ph.D., is a professor in Psychiatry and Behavioral Neuroscience and Director of the Division of Psychology at Oregon Health & Science University. He is a leading researcher in the field of ADHD and the author of over 200 scientific papers related to the neuropsychological, cognitive, and temperamental correlates of childhood ADHD; to ADHD genetics; and to MRI-based research and theoretical interpretations of brain development in ADHD. He is the author of Getting Ahead of ADHD, a book for parents that addresses lifestyle and environment approaches to ADHD. (#CommissionsEarned) He also maintains a blog via Psychology Today. For more information, visit Dr. Nigg’s personal webpage here.

#CommissionsEarned As an Amazon Associate, ADDitude earns a commission from qualifying purchases made by ADDitude readers on the affiliate links we share. However, all products linked in the ADDitude Store have been independently selected by our editors and/or recommended by our readers. Prices are accurate and items in stock as of time of publication.

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• ADHD and trauma often co-occur in ways we are still trying to understand.
• PTSD and ADHD symptoms can overlap and exacerbate one another.
• People with ADHD are more likely to have high scores on the Adverse Childhood Experiences Questionnaire (ACEs), meaning that there is greater likelihood of
  trauma.
• Clients and clinicians should give trauma history and ADHD equal consideration in treatment.
• ADHD clinicians should perform comprehensive trauma screenings, then make treatment recommendations accordingly.
• Neither ADHD nor traumatic stress is your fault. They are not character
  flaws.

Traumatic stress and ADHD share significant associations, according to a growing body of research on trauma and childhood maltreatment. Studies show that people with ADHD score higher than their neurotypical peers on the Adverse Childhood Experiences (ACEs) questionnaire¹, which measures the impact of negative, stressful, or traumatic events on well-being. This means that they are likely to report troubling events like domestic violence, caregiver substance abuse, physical or sexual abuse, neglect, mental illness, poverty, and community violence. Experiences of racism, discrimination, and oppression can also lead to trauma.

So what is the connection between trauma and ADHD? How to we tease apart the diagnoses? What do their similarities mean for symptoms, diagnosis, and treatment? Here’s what you need to know about traumatic stress and ADHD.

1. Untreated ADHD Can Lead to Trauma

In considering the relationship between ADHD and trauma, we must first acknowledge that some of us start with greater access to resources than do others. Not having access to services for ADHD symptoms, being invalidated or dismissed by professionals, or going without an accurate diagnosis and treatment can lead to years of unnecessary distress, impairment, and neglect.

2. Traumatic Stress Can Worsen ADHD Symptoms

While research tells us that exposure to traumatic events can exacerbate ADHD symptoms, it doesn’t mean that trauma causes ADHD. Epigenetics — how genes might be turned on or off based on our environment — is key to understanding the role that trauma might have in leading to ADHD symptoms. Scientists are studying exposure to toxins, as well as nutrition, lifestyle, and stress levels, to learn what might make ADHD genes turn on or become activated.

[Read: A Complete Overview of Childhood Trauma and ADHD]

We need a better understanding of what ADHD really is and why it presents in unique and individual ways and at various ages. Trauma responses, in utero and/or at a young age, could trigger the development of ADHD symptoms. Research has shown that exposure to trauma changes the brain. This is essential to consider when evaluating or seeking out a diagnosis for ADHD.

3. Rejection Sensitive Dysphoria and Trauma Require Further Study

People with ADHD can become strongly emotionally triggered by perceived rejection or anticipation of judgment, often because of hurtful past experiences related to their differences. This is called Rejection Sensitive Dysphoria. RSD is not a clinical diagnosis, but it is important to contextualize this sensitivity as one being triggered by events that recreate past wounding experiences while living with ADHD. More research needs to be done to determine how RSD emerges in people with ADHD and how it could be a manifestation of a trauma response.

4. Trauma Can Be Misdiagnosed as ADHD

Both ADHD and trauma affect the functioning of the pre-frontal cortex — which controls executive functioning skills and reasoning — and the amygdala, which processes emotions. This can lead to hyperarousal or restlessness; difficulty with emotional regulation and making decisions; sleep problems; impulsivity; addictive behaviors; and difficulty relating to others.

[Understand: The Science of Fear]

How do clinicians tell the difference? We do the best we can by taking an in-depth trauma history and exploring the lived experience of each client, in addition to conducting traditional ADHD assessment procedures.

5. Trauma Screenings Should Be Part of Every ADHD Assessment

All ADHD assessments should include questions about trauma. Clinicians should perform comprehensive screenings that use both direct questions and more open explorations of a patient’s lived experiences over time (especially since trauma can sometimes take time to manifest).

Not everyone who experiences trauma will meet the full criteria for post-traumatic stress disorder (PTSD). Some people who do not meet the full criteria will still struggle with complicated impacts of traumatic stress, while others might not have symptoms at all.

When trauma occurs later in life, the diagnostic picture is a bit clearer, because a doctor can ask whether ADHD symptoms were present before the trauma occurred. The picture is more nuanced if the trauma occurred in childhood or is ongoing (developmental or attachment trauma). In these cases, clinicians must consider the client’s unique personality and lived experiences, and conduct treatment carefully.

ADHD and symptoms related to trauma, such as PTSD, can co-occur and exacerbate each other, so the presence of both leads to more problems than occur with ADHD or PTSD alone.

In all, to develop an effective treatment plan, it is vital that a person with ADHD find a clinician who inquires about trauma during the course of an ADHD evaluation. As for treatment, patients should look for providers who have been trained in Eye Movement Desensitization and Reprocessing or cognitive processing therapy. Both of these therapies reduce trauma symptoms, and they have been validated by extensive research.

ADHD and Trauma: Next Steps

• Free Download: How Is ADHD Diagnosed?
• Read: ADHD and Trauma: Untangling Causes, Symptoms & Treatments
• Read: The Relationship Between PTSD and ADHD: Symptoms, Diagnosis, Treatment

SUPPORT ADDITUDE
Thank you for reading ADDitude. To support our mission of providing ADHD education and support, please consider subscribing. Your readership and support help make our content and outreach possible. Thank you.

Sources

¹ Brown, N. M., Brown, S. N., Briggs, R. D., Germán, M., Belamarich, P. F., & Oyeku, S. O. (2017). Associations Between Adverse Childhood Experiences and ADHD Diagnosis and Severity. Academic pediatrics, 17(4), 349–355. https://doi.org/10.1016/j.acap.2016.08.013

More frequent television use at 11 years and greater total screen time at 18 years are linked to a higher likelihood of ADHD diagnosis at 22 years of age, according to a general population longitudinal study published in the Journal of Attention Disorders.¹

Researchers studied the records of 2,333 participants without diagnosed ADHD who participated in the 1993 Pelotas Birth Cohort Study through age 22. Researchers studied participants’ time spent using television, video games, and computers at ages 11, 15, and 18, and then they assessed for ADHD at 22 years.

Research found that time spent watching television at ages 11 and 18 was positively correlated with the presence of future ADHD symptoms. This finding is corroborated by other, similar research. Children of participants in the 1972 Birth Cohort from Dunedin, New Zealand, who watched 2 hours, and particularly those who watched 3 hours, of television per day between the ages of 5 to 11 years were found to have above-average symptoms of poor attention at 15.² Similarly, a U.S. study found that 14-year-olds who viewed television for three or more hours per day were more likely to have one or more symptoms of ADHD at age 16, compared to adolescents who watched less than three hours per day.³

The new study also demonstrated positive correlations between later ADHD symptoms and video-game use at age 15, as well as computer use at age 18. It yielded a statistically significant but modest relationship between total screen time and subsequent diagnosis of ADHD in adolescents. Researchers concluded that additional research is necessary to establish whether this association is causal, including information about what was watched on each device and the time spent on different devices.

Sources

¹ Soares PSM, de Oliveira PD, Wehrmeister FC, Menezes AMB, Gonçalves H. Is Screen Time Throughout Adolescence Related to ADHD? Findings from 1993 Pelotas (Brazil) Birth Cohort Study. Journal of Attention Disorders. March 2021. doi:10.1177/1087054721997555

² Landhuis, C. E., Poulton, R., Welch, D., Hancox, R. J. (2007). Does childhood television viewing lead to attention problems in adolescence? Results from a prospective longitudinal study. Pediatrics, 120(3), 532–537.

³ Johnson, J. G., Cohen, P., Kasen, S., Brook, J. S. (2007). Extensive television viewing and the development of attention and learning difficulties during adolescence. Archives of Pediatrics & Adolescent Medicine, 161(5), 480–486.

Caregiver wellbeing — namely poor physical health, mental health, and/or employment status — is associated with increased symptoms of ADHD in toddlers, according to a new study published in the Journal of Attention Disorders.¹ The causality of this relationship remains unclear, though the findings could suggest including caregiver wellness screenings in early childhood pediatric appointments and ADHD evaluations.

Researchers examined the relationship between social determinants of health (SDH) and ADHD symptoms in a national sample of 7,565 preschool-age children using exploratory factor analysis (EFA) and exploratory structural equation modeling (ESEM).

Independently, socioeconomic status, access to basic needs, and caregiver wellbeing were all significantly associated with higher symptoms of ADHD. However, researchers found that socioeconomic status and access to basic needs were no longer significantly associated with ADHD symptoms in the model that included all three factors: only worse caregiver wellbeing (β = .39, p < .01) was significantly associated with ADHD symptoms.

One possibility for these findings is that “poor caregiver health may decrease the quality time spent by a caregiver with their child, thus leading to or exacerbating ADHD symptoms in young children,” or that “ADHD symptoms in young children worsen caregiver health and reduce likelihood of employment.”

This is the first study to suggest that the association between social detriments of health and ADHD is fully mediated by worse caregiver wellbeing, instead of poverty itself. These findings speak to the importance of interventions focused on the health of caregivers with young children that could mitigate the severity of symptoms of ADHD in toddlers.

Sources

¹Spencer AE, Oblath R, Sheldrick RC, Ng LC, Silverstein M, Garg A. Social Determinants of Health and ADHD Symptoms in Preschool-Age Children. Journal of Attention Disorders. March 2021. doi:10.1177/1087054721996458