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If you've ever lain in bed staring at the ceiling for what feels like forever, you know the pain of insomnia. The missed opportunity for sleep is bad enough, not to mention the worry about what it will mean for your performance the next day.
I've written elsewhere about the best way to treat chronic insomnia, which involves cognitive behavioral therapy for insomnia (CBT-I). If you've battled insomnia for years and have tried everything else, give CBT-I a try; if you've never tried treatment for your insomnia, CBT-I is a great place to start.
But how can we prevent chronic insomnia in the first place? To answer this question I spoke with Dr. Michael Perlis, a psychologist and sleep specialist at the University of Pennsylvania. Dr. Perlis works at the frontier of sleep medicine, and has played a key role in developing CBT-I; he's the first author on a therapist guide for CBT-I entitled Cognitive Behavioral Treatment of Insomnia: A Session-by-Session Guide.
Let's start by distinguishing between two different types of insomnia.
What Is Acute Insomnia?
Insomnia means trouble sleeping, whether it happens at the beginning, middle, or end of the night. As Dr. Perlis explains, "Insomnia includes not being able to fall asleep or stay asleep, or waking up too early in the morning." Those difficulties can last a short time (acute) or a long time (chronic), and the distinction matters. So what is acute insomnia?
Michael L. Perlis: Somewhere between a few days and two weeks of three or more days per week is often considered the threshold of acute insomnia. Some people go as much as a few days to three months before they call it "chronic," so everything before three months is considered acute insomnia.
Acute Insomnia Is Very Common—and Most People Recover
Most of us have experienced acute episodes of insomnia, as you've probably heard the people you know describe from time to time. New research is confirming just how common acute insomnia is, and how likely it is that people recover before it becomes chronic.
MLP: We just finished a study of a national sample of about 1500 people who started as good sleepers. They completed questionnaires for us quite frequently: daily sleep diaries, weekly measures of insomnia. And we just watched. And it was astounding—in confirmed good sleepers, around thirty percent had acute insomnia in one year. In England, the same study was done with a colleague of mine and he found fifty percent. That's a lot of people. The interesting thing is that ninety percent of people who have acute insomnia recover.
Unlike Chronic Insomnia, Acute Insomnia Is Unrelated to Age
Acute insomnia is relatively "equal opportunity," meaning it doesn't discriminate by age—which raises important questions about its function.
MLP: There is a belief—and it's true—that as we get older decade by decade, the rate of chronic insomnia goes up. One of the things I'm working on in the data set is to see if this humongous incidence of acute insomnia varies by age, but so far it doesn't—which is really telling you something. If a humongous percentage of the population has acute insomnia now and again, like once every three or four years, and it doesn't differ by age the way chronic insomnia does, which gets more and more prevalent with each passing decade—how "abnormal" is that? Popularity is not a great way to define normal, but it is a way, and if something is highly prevalent and doesn't vary the way the chronic form of it does, you start to wonder if this is normal. And then you start to wonder, How could that be?
Acute Insomnia Is Usually Linked to Stress
So what causes acute insomnia? Many factors can be involved, and most of them involve stress. The stress may be related to physical pain, illness, worry, or that argument you had with your sibling earlier in the day. As Dr. Perlis points out, it makes sense that our bodies at times make sleep a lower priority. As the late Dr. Art Spielman, another major figure in the insomnia treatment, said, "Sleep is adaptively deferred when the lion is at the mouth of the cave."
MLP: There has to be an override when there is a perceived or real threat, to disable the normal governance of sleep, so that you can stay awake and run or fight. So acute insomnia is part of the fight-or-flight response, such that if you are under siege and at mortal threat, don't sleep. And that's a good thing.
But why would our brains override the sleep drive when stress is more psychological, like having big deadlines at work? Is that just a function of our stress response, which doesn't distinguish between physical danger and psychological distress?
MLP: You can argue, "Maybe for the caveman living on the savannah, evolutionarily speaking, that was important... But now it's not adaptive at all, it's just bad. We're responding with inappropriate levels of fight/flight response, of being adrenalized, because I'm worried about work? Because I've got some financial problems? Those are not life-threatening. I shouldn't lose sleep over that." And I hear that, and maybe this is vestigial, or maybe it's not. Maybe insomnia is what you're begging for when you're under stress. What is insomnia but the gift of more time? It's what you're begging God for—"If only I had a 40-hour day, I could get all this stuff done!" You asked, you got it. So maybe it's still adaptive in its acute form.
What Turns Acute Insomnia into Chronic Insomnia?
It's harder to make a case that chronic insomnia serves some adaptive function, especially since it can stick around long after the stress is resolved. The best way to keep our sleep as healthy as possible and to get it back on track from acute insomnia is to match sleep opportunity (how much time we spend in bed) to sleep ability (how long we're able to sleep), as Dr. Perlis explains.
Seth J. Gillihan: If only a fraction of people with acute insomnia go on to have chronic insomnia, what underlies that transition? If we can't say for sure how much sleep a typical person needs, how much time should a person plan to spend in bed from when they lie down to go to sleep to when they get up for the day?
MLP: The easy answer is, whatever sleep opportunity you give to yourself, if your obtained sleep isn't 90% of that time, you're in bed for too long. If you're in bed for 10 hours and you can sleep 5 of that, that's a mismatch between sleep opportunity and sleep ability. So in this way, we can individualize and tailor to the individual. This is actually a part of what CBT-I does—identify the magnitude of the mismatch. But what do people naturally do? According to the gospel of Art Spielman, they do one thing in particular, in theory—which is in theory why CBT-I works. At some point, after you've had a few bad nights–maybe it's one bad night, maybe it's fifteen bad nights—some people say, "I've had enough. I'm going to bed earlier so I can get more sleep." That is referred to as the mortal sin of sleep extension. It probably kicks in for people who have higher sleep needs, but the idea is that what transitions you to chronic insomnia is that you are expanding your sleep opportunity to recover lost sleep, and that's a problem because you don't have that sleep ability. The minute you put into place a compensatory behavior like sleep extension, you're basically guaranteeing the insomnia will continue.
Dr. Perlis's recent study will provide a large sample in which to test this theory, and the results should be available soon. In the meantime, he offered an alternative hypothesis about what leads to chronic insomnia:
MLP: There is another possibility that is less obvious. It might be that transitioning from acute insomnia is not about extending sleep opportunity—the tendency to try to recover lost sleep, like going from a sleep period of 8 to 10 hours. It might be something more benign, which is the failure to sleep restrict. What that means is, it might just be that you stay at 8, even though your ability has dropped to 7 or 6. And the people who are more likely to do that are the ones who are suffering from sleep loss, who have a higher sleep need.
So what's the bottom line? It's a simple answer, but not an easy one.
MLP: At the end of the day, if you experience several days of insomnia, or even one, you know the solution? Do nothing. There's your solution. It is the hardest nothing you'll ever do, because your body will be screaming at you to do something. If you do absolutely nothing—get up at the same time, don't nap, don't go to bed early, which your body will want you to do... If you maintain your normal sleep schedule, the odds are the insomnia will abate in 3-to-5 days, and we have data for that. The ship rights itself if you leave it alone.
The full interview with Dr. Perlis is available here.
References
Perlis, M. L., Jungquist, C., Smith, M. T., & Posner, D. (2006). Cognitive behavioral treatment of insomnia: A session-by-session guide. New York: Springer Science & Business Media.
