Sleep & Mornings

How Sleep Deprivation Looks a Lot Like ADHD

Inadequate sleep can cause procrastination, forgetfulness, and inattention among other symptoms often mistaken for ADHD. Learn the telltale signs of a sleep deficit, and how to get the rest you need.

A woman sleeps well into the day after experiencing symptoms of insomnia the night before.
A woman sleeps well into the day after experiencing symptoms of insomnia the night before.

Several years back, a new patient came to see me to find out if he had ADHD. He had all the classic symptoms: procrastination, forgetfulness, a propensity to lose things, and, of course, the inability to pay attention consistently. But one thing was unusual. His symptoms had started only two years earlier, when he was 31.

I treat a lot of adults for ADHD, but the presentation of this case was a violation of an important diagnostic criterion: Symptoms must date back to childhood. It turned out that he first started having these problems the month he began his most recent job, one that required him to rise at 5 a.m., despite the fact that he was a night owl.

The patient didn’t have ADHD, I realized, but symptoms of insomnia, which caused a chronic sleep deficit. I suggested some techniques to help him fall asleep at night, like relaxing for 90 minutes before getting into bed at 10 p.m. If necessary, he could take a small amount of melatonin. When he returned to see me, two weeks later, his symptoms were almost gone. I suggested that he call if they recurred. I never heard from him again.

The Sleep Theory For ADHD

Many theories are thrown around to explain the rise in the diagnosis and treatment of ADHD in children and adults. According to the Centers for Disease Control and Prevention, 11 percent of school-age children have now received a diagnosis of the condition. I don’t doubt that many people do, in fact, have ADHD; I regularly diagnose and treat it in adults. But what if a substantial number of cases are sleep disorders in disguise?

For some people — especially children — sleep deprivation does not necessarily cause lethargy; it makes them hyperactive and unfocused. Researchers and reporters are increasingly seeing connections between dysfunctional sleep and what looks like ADHD, but those links are not yet understood by parents and doctors.

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We all get less sleep than we used to. The number of adults who reported sleeping fewer than seven hours each night went from 2 percent in 1960 to more than 35 percent in 2011. Good sleep is crucial for children, who need delta sleep — the deep, rejuvenating, slow-wave kind — for proper growth and development. Yet today’s youngsters sleep about an hour less than children did a hundred years ago. And for all ages, stressful daytime activities — marked by nonstop 14-hour schedules and inescapable melatonin-inhibiting iDevices — often impair sleep. It might be a coincidence, but our sleep-restricting lifestyle became more extreme in the 1990s, the decade that saw the explosion in ADHD diagnoses.

A number of studies have shown that a huge proportion of children with an ADHD diagnosis also have sleep-disordered breathing, like apnea or snoring, restless leg syndrome, or non-restorative sleep, in which delta sleep is frequently interrupted. One study, published in 2004 in the journal Sleep, looked at 34 children with ADHD. All of them showed a deficit of rejuvenating delta sleep, compared with only a handful of the 32 control subjects.

A 2006 study in the journal Pediatrics showed something similar, from the perspective of a surgery clinic. This study included 105 children between ages five and 12. Seventy-eight of them were scheduled to have their tonsils removed because they had problems breathing in their sleep, while 27 children scheduled for other operations served as a control group. Researchers measured the participants’ sleep patterns and tested for hyperactivity and inattentiveness, consistent with standard protocols for validating an ADHD diagnosis. Of the 78 children getting the tonsillectomies, 28 percent had ADHD, compared with only 7 percent of the control group.

Even more stunning was what the study’s authors found when they followed up with the children. A full half of the original ADHD group who received tonsillectomies — 11 of 22 children — no longer met the criteria for the condition. In other words, what had appeared to be ADHD had been resolved by treating a sleeping problem.

But ADHD-like symptoms may persist even after a sleeping problem is resolved. Consider the long-term study of more than 11,000 children in Britain, published three years ago, also in Pediatrics. Mothers were asked about symptoms of sleep-disordered breathing in their infants when they were six months old. Then, when the children were four and seven years old, the mothers completed a behavioral questionnaire to gauge their children’s levels of inattention, hyperactivity, anxiety, mood disorders, and problems with peers, conduct, and social skills.

The study found that children who suffered from sleep-disordered breathing in infancy were more likely to have behavioral difficulties later in life — 20 to 60 percent more likely to have behavioral problems at age four, and 40 to 100 percent more likely to have such problems at age seven. These problems occurred even if the disordered breathing had abated, implying that an infant’s breathing problem might cause some kind of potentially irreversible neurological injury. There is more going on in the nocturnal lives of our children than any of us have realized. Typically, we see and diagnose only their downstream, daytime symptoms.

There has been less research into sleep and ADHD after childhood. But a team from Massachusetts General Hospital found, in one of the few studies of its kind, that sleep dysfunction in adults with ADHD closely mimics the sleep dysfunction in children with ADHD. There is also some promising research being done on sleep in adults, relating to focus, memory, and cognitive performance. A study published several years ago in the journal Nature Neuroscience found that the amount of delta sleep in seniors correlates with performance on memory tests. And a study published several years ago in the journal Sleep found that while subjects who were deprived of sleep didn’t necessarily report feeling sleepier, their cognitive performance declined in proportion to their sleep deprivation and continued to worsen over five nights of sleep restriction.

[Wired, Tired, & Sleep Deprived]

As it happens, “moves about excessively during sleep” was once listed as a symptom of attention-deficit disorder in the Diagnostic and Statistical Manual of Mental Disorders. That version of the manual, published in 1980, was the first to name the disorder. When the term ADHD, reflecting the addition of hyperactivity, appeared in 1987, the diagnostic criteria no longer included trouble sleeping. The authors said there was not enough evidence to support keeping it.

What if doctors, before diagnosing ADHD in their patients, did have to find evidence of a sleep disorder? Psychiatric researchers typically don’t have access to the equipment or expertise needed to evaluate sleep challenges. It’s tricky to ask patients to keep sleep logs or to send them for expensive overnight sleep studies, which can involve complicated equipment. (And getting a sleep study approved by an insurance company is by no means guaranteed.) As it stands, ADHD is usually diagnosed with only an office interview.

Some of my patients have resisted my referrals for sleep testing, since everything they have read identifies ADHD as the culprit. People don’t like to hear that they may have a different, stranger-sounding problem that can’t be fixed with a pill — though this often changes once patients see the results of their sleep studies.

ADHD And Sleep: It’s Personal

Beyond my day job, I have a personal interest in ADHD and sleep disorders. Beginning in college, and for nearly a decade, I struggled with profound cognitive lethargy and difficulty focusing, a daily nap habit, and weekend oversleeping. I got through my med school exams only by the grace of memorization skills and the fact that ephedra was still a legal supplement.

I was misdiagnosed with various maladies, including ADHD. Then I underwent two sleep studies and was found to have an atypical form of narcolepsy. This was a shock to me, because I had never fallen asleep while eating or talking. But, as it turned out, over 40 percent of my night was spent in REM sleep — or “dreaming sleep,” which normally occurs only intermittently throughout the night — while just 5 percent was spent in rejuvenating delta sleep. I was sleeping eight to 10 hours a night, but I still had a delta sleep deficit.

It took some trial and error, but with the proper treatment, my cognitive problems came to an end. Today, I eat well and respect my sleep needs instead of trying to suppress them. I also take two medications: a stimulant for narcolepsy and, at bedtime, an SNRI (or serotonin-norepinephrine reuptake inhibitor) antidepressant — an off-label treatment that curtails REM sleep and helps increase delta sleep. Now my daytime focus is remarkably improved.

Attention-deficit problems are not the only reasons to take lack of quality sleep seriously. Laboratory animals die when they are deprived of delta sleep. Chronic delta sleep deficits in humans are implicated in many diseases, including mood disorders, heart disease, hypertension, obesity, diabetes, and cancer, not to mention thousands of fatigue-related car accidents each year. Sleep disorders are so prevalent that
every internist and psychiatrist should screen for them.

The National Institutes of Health spent only $233 million on sleep research in 2013, a decrease from 2012. One of the problems is that the research establishment exists as mini-fiefdoms — money given to one sector, like cardiology, rarely makes it into another, like sleep medicine, even if they are intimately connected.

Adults with ADHD can’t wait any longer to pay attention to the connection between delta sleep and ADHD. If you’re not already convinced, consider the drug clonidine. It started as a hypertension treatment, but has been approved by the Food and Drug Administration to treat ADHD. Studies show that when it is taken only at bedtime, symptoms improve during the day. Many physicians may not know that clonidine can be a potent delta sleep enhancer.

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This piece was originally published in The New York Times.