THE MYSTERY. How can one symptom, insomnia, have so many different causes? Can we identify the factors and conditions that may be contributing to the insomnia and help insomniacs get a good night’s sleep?
A patient in her seventies had been referred to me by her family doctor for evaluation of her insomnia. The woman was thin and nervous. She had not combed her hair. She told me it usually took her three to four hours to fall asleep, and once she did she would wake up after an hour or two and be unable to sleep again. She assured me that she did not have continuous movement or restlessness in her legs either at night or in the daytime. Nor was she fidgety. She did not toss and turn; she lay perfectly still in bed whether she slept or not. She did not know whether she snored because she lived alone. When she did fall asleep, she sometimes awakened from a terrible nightmare drenched in perspiration. I asked her whether she was frustrated at not being able to fall asleep quickly, and she said no. Her difficulty sleeping through the night had gone on for so long that she was used to it. When she woke up, she did not have acid in her mouth, heartburn, hunger, chest pain, shortness of breath, or other unpleasant sensations. I was stumped until I asked her how long she’d had the problem and whether she could remember when it started. She told me that she remembered the exact night it started, over twenty years earlier.
Sleep scientists define insomnia as having at least one of the following symptoms: difficulty falling asleep, difficulty staying asleep, or waking up very early in the morning in conjunction with impaired daytime function. For many people the underlying problem is hyperarousal (the nervous system is jazzed up) even during the daytime; their brains show more metabolic activity in parts of the brain involved with arousal than average in the daytime.
For many people insomnia is not a disease. It is itself a symptom of a disease or other condition. Insomnia is present with many underlying problems, including psychological and psychiatric disorders; medical disorders such as diseases of the heart, lungs, and kidneys; disorders associated with women’s life transitions, such as menarche and menopause; and as a side effect of certain medications. Not all people with the conditions just mentioned have insomnia. Scientists believe that the condition along with the hyperaroused brain is what leads to the insomnia and have come up with the term “comorbid insomnia” to define it.
Thus, for people who have trouble falling or staying asleep one of the following might be the underlying cause:
Premenstrual syndrome (see Chapter 3)
Pregnancy (Chapter 4)
Hot flashes (Chapter 5)
Difficulties at home (Chapter 7)
Body clock differences (Chapter 8)
An unusual work schedule (Chapter 9)
Restless legs syndrome (Chapter 11)
Medical conditions (Chapter 15)
Psychiatric conditions (Chapter 16)
Medications (Chapter 17)
In this chapter I review issues that are important to all people with insomnia, focusing on the types of insomnia that are not associated with other conditions.
Insomnia is not just a problem among overstressed and overworked North Americans. It is widespread in every country in which it has been studied, including France, Germany, Great Britain, the Scandinavian countries, Australia, and Japan. In all these places, certain patterns emerge. Insomnia is common and more frequent among women and older people. One study from Sweden determined the percentage of thirty-eight-year-old women who had sleep problems and compared this with the percentage of the same women who had sleep problems twenty-two and twenty-four years later. The rate of insomnia had doubled. When they were younger, 17 percent of the women studied had sleep problems; when the same women were tested later, 35 percent had sleep problems.
Insomnia is also more common among women than men. A U.S. poll reported in 2002 found that more than half (58 percent) the adult population suffered from insomnia a few nights a week or more; 63 percent of those reporting insomnia were women. Thirty-five percent of the adults in the sample reported that they had symptoms of insomnia nightly or almost every night. According to the survey, insomnia seems to be more common in households with children, among people who are in poor health, and among shift workers. Compared to people who had insomnia a few nights a week, those people surveyed who rarely or never had insomnia tended to consider themselves full of energy, optimistic, happy, relaxed, satisfied with life, and peaceful. People not getting enough sleep described themselves as likely to become impatient and irritable and to make more mistakes. A 2015 study found that people with painful conditions are much more likely to have insomnia and decreased amount of sleep.
Using the definition of insomnia that includes daytime symptoms (sleepiness, fatigue, poor memory), scientists estimate that about 10 to 15 percent of adults worldwide have chronic insomnia.
Sometimes what is perceived as abnormal in fact falls within the normal behavioral range. People sometimes consult a doctor about a symptom that causes them distress but that is not a medical problem. What such people require is reassurance that nothing is wrong. I have had many patients, for example, who find taking thirty minutes to fall asleep distressing, whereas others find it unremarkable. For some, any delay in falling asleep seems endless. Most of the patients that I have seen who suffer from insomnia take more than forty-five minutes to fall asleep.
Over the years, I have seen many patients who have told me that they sleep only six or seven hours a night; they therefore assume they must have insomnia. Many request that I prescribe sleeping pills because they have read that they should be sleeping eight or nine hours a night. I then ask them how they feel during the day and how productive they are. If they say that they feel wide awake and alert and they are functioning at a high level, I tell them that they are among the lucky people who can need less sleep than the rest of the population. Though there are recommendations for the ideal amount of sleep, there is no single number that defines the optimal amount of sleep for each person. Each individual seems to have an optimal number. But although some people recognize how much sleep works best for them, others are unsure of the amount and think they are not getting enough.
If you are uncertain how many hours of sleep you need, try the following experiment. For the next two weeks, record the amount of sleep you have during the night and rate your daytime functioning at the end of the day on a scale from 1 (worst functioning I’ve ever had) to 10 (best functioning I’ve ever had). You can rate how productive you are at work, your performance at hobbies and other activities, and how you interact with your family. After two weeks, look at the relationship between your nightly sleep and your next-day functioning. Pay specific attention to whether your sleep amount seems to be highly associated with your next-day functioning. Some people notice, for example, that there are days they function well on relatively little sleep and days they function poorly despite having had a relatively long night’s sleep. What most people will learn is that they function better and feel better when they have slept more.
Some people have trouble sleeping not because they have a medical problem, but because their environment does not encourage sleep. Too much light in the room can keep people awake or wake them up early in the morning. Good window shades can take care of this. Excessive noise from outside the house (buses, cars, or airplanes) or inside the house (music or television, smart-phone notifications) can keep people awake. Wearing earplugs, using noise machines, or turning off the gadgets that ping all night such as smartphones can help. People might also have trouble falling asleep if the temperature is too hot or too cold. This too can be adjusted.
Whenever I travel and stay in a hotel, I always ask for a quiet room facing away from the street, elevators, and ice machines; I also ask for a room without a feather pillow or down comforter. Why no feathers? I learned many years ago, when I was a child, that I was allergic to feathers. Someone who wakes up in the middle of the night with a stuffy nose or sneezing might also be allergic to feathers in the bedding.
People spend on average one-third of their lives in bed—they should make sure that it is not itself the cause of a sleep problem. Is the bed comfortable? Many people have beds that are too firm. Others don’t realize that mattresses and even bed frames should be replaced if they are impeding sleep, and they spend their nights trying to sleep on a bed that is lumpy or has a depression in the middle. Another problem is trying to sleep in a bed that is not the right size. Teenagers may suddenly outgrow the standard single bed they have been comfortably sleeping in for many years. Bed partners should take particular care to find a bed in which they will both be comfortable. Both partners may not find the same mattress comfortable and may need to make adjustments. A short “test drive” in the store may not be enough time to determine whether a bed is right; consumers should always make sure before they buy a bed that they can return or exchange it after they have tried sleeping in it. Travelers who find a hotel mattress especially comfortable should ask what brand it is and what model the bed is. Some hotels will sell and ship mattresses to their guests.
People who are really sleepy can sleep almost anywhere, on any surface, but the more comfortable the surface, the better they sleep. A 2012 poll found that the mattress, pillows (on average Americans use two when they sleep), and even fresh scent of sheets all contribute to the quality of people’s sleep. But what is true in the United States might not be true in other countries. The ideal conditions for sleeping vary from country to country. In traditional hotels in Japan, for example, a guest might be offered a buckwheat-filled or hard wooden “pillow” and a mat to sleep on.
But just as insomnia might not be a problem in itself but the result of an adjustable environmental factor, it can also be a symptom of a factor that has nothing to do with environment. Two different neighbors of mine came home from a health fair, each with a $6,000 bed. One challenged me to lie in his, and it was certainly comfortable. But did their fancy beds cure their insomnia? No. This is because their insomnia was not caused by their beds. One had severe pain from a back injury, the other was a heavy smoker who would wake up to smoke at night. For them, the insomnia was a different kind of symptom.
People who develop insomnia as a result of stress or pain should learn ways to manage or minimize the symptoms; otherwise they risk developing behaviors that perpetuate the insomnia, even after the original cause of the problem has disappeared.
Anyone who has taken a psychology course—and a lot of people who haven’t—has heard of Pavlov’s dog. In the early twentieth century, the physiologist Ivan Pavlov conducted an experiment in which he rang a bell and then presented a dog with food. Initially the prospect of food made the dog drool; Pavlov would then measure the drool. After repeated sessions in which Pavlov rang the bell and presented the food—reinforcing the dog’s drooling—the dog started to drool whenever it heard the bell, even when Pavlov did not give it any food. The dog’s behavior showed that it now associated the ringing of the bell with the presentation of food. The significant finding was that the dog had learned this behavior. (This is why a conditioned or learned response to a situation is often called a Pavlovian reflex.)
People also develop conditioned or learned responses. Some people enjoy eating a bag of popcorn when they go to the movies. Over time, if they continue to have popcorn when they go to the movies, they will find that the very act of going to the movies elicits an urge to eat popcorn. For many people, even if they have just eaten a large dinner, the first thing they notice when they walk into a movie theater is the urge to eat a bag of popcorn.
Insomnia can also be learned. Say, for example, that a man suffers a painful back injury that prevents him from falling asleep. In the days and weeks following this injury, as he becomes more and more frustrated about his inability to fall asleep, he begins to associate his bed with that frustration. Even after his injury has healed he suffers from insomnia, yet now it is caused not by the pain but by a new problem, his learned behavior. He now associates the bed with insomnia. No matter how tired he feels when he goes to bed, once he gets into bed, he immediately feels wide awake and alert—the bed itself has become a cue for sleeplessness. And because he gets so little sleep, he attempts to keep alert during the day by drinking large amounts of coffee. But caffeine, especially if taken close to bedtime, can worsen insomnia, thus perpetuating it.
Another common source of learned insomnia is anxiety. Many people have trouble falling asleep before going on a trip. They are worried about whether they will wake up on time or whether there will be other problems, and this anxiety causes them to sleep fitfully. After the trip, if all goes well, everything is fine. But before the next trip, they experience exactly the same anxiety and insomnia until eventually they connect going on a trip with not being able to sleep the night before. When someone expects to have a bad night’s sleep, he or she usually experiences a bad night of sleep, and learned insomnia is surprisingly common.
People who experience insomnia very rarely or only at particular times, therefore, probably have nothing to worry about. They can try certain strategies, listed below, to overcome it. But those who have trouble falling asleep most nights and then experience frustration, anxiety, and difficulty in functioning the following day, do have cause for concern. If none of the common cures for insomnia help, they need to bring the problem to the attention of their primary caregiver. He or she, in turn, might direct them to see a specialist in sleep disorders.
1. Use the bedroom for sleep and sex only.
2. If you can’t fall asleep, after fifteen to twenty minutes get out of bed and do something else that is relaxing.
3. Avoid any activity that might cause your brain to become excessively aroused before going to sleep. Avoid arguments, discussions about money or major problems, and exciting television or books. Avoid any vigorous activity for four to five hours before bedtime (sex appears to be the major exception). Turn off all gadget screens an hour before bedtime.
4. Do not consume heavy or spicy meals, which might cause heart-burn or discomfort. You want to feel neither full nor hungry before going to bed.
5. If you use an alarm clock, turn it away from you. Do not check the time throughout the night.
6. Establish a relaxing bedtime ritual, such as reading soothing books.
7. If you have nighttime caregiving duties (children, elderly parents, pets), share them.
8. Avoid daytime or evening naps (especially in the four to five hours before bedtime). If you must take a nap, make sure that it is not more than twenty minutes long.
9. Get plenty of exercise but not too close to bedtime.
10. Restrict your time in bed. Spending more time in bed than you need may lead to poor sleep.
11. Take a warm bath or have a hot drink (without alcohol or caffeine) to help you relax.
12. Cut down or eliminate cigarette smoking. Limit caffeine dramatically; if the insomnia is severe, avoid caffeine after lunch. Reduce your consumption of alcohol, which can disrupt sleep.
13. If the insomnia persists, consult your doctor: a medication or a disease might be causing the insomnia.
I discuss other strategies for dealing with insomnia in Chapters 19 and 20.
Any type of stress can result in difficulty falling or staying asleep. Examples of situational stress that can cause insomnia include an exam, a meeting, or a trip the next day. Examples of chronic stress might include marital strife, separation, or divorce; financial difficulties; illness in oneself or a family member; or problems in the workplace. Some stresses are out of the sufferer’s control and relate to outside factors unconnected to his or her environment. The acute stress Americans felt after the terrorist attacks of September 11, 2001, for example, resulted in a spike in cases of insomnia in the United States. The number of people using medication to help them sleep at least a few nights a month increased from 11 percent of the population to 15 percent. Other examples of this type of stress are unstable international politics that might lead to war or a downward spiral in the national or international economy. Human sleep can be affected by something as intimate as a personal relationship or something as impersonal as a war or witnessing violence thousands of miles away.
For most people, their sleep returns to normal when the factor causing the stress is removed (unless there are psychophysiological factors at work). In a situation in which the stressful situation is expected to be brief but the sleep disruption is severe, medication can be effective. Patients should speak to their doctor about what types of medication are available, the benefits and disadvantages of each, and their costs. (I discuss these medications further in Chapter 20.) Insomnia related to stressful situations is generally expected to improve without treatment, so sufferers should try first to get through their difficult periods without drugs.
In most situations, even when stress occurs over months or years, sleep does return to normal. But there are cases in which the insomnia continues long after the cause of stress has ended. I have seen people in my clinical practice who at one time in their life suffered some enormous stress that was still causing symptoms of insomnia fifty years later. Many Holocaust survivors, to take an extreme case, continue to have trouble falling and staying asleep. Many still suffer from terrible nightmares. Some also suffer from posttraumatic stress disorder, a serious psychiatric condition that is discussed further in Chapter 16.
When a stressful situation is not improving and insomnia continues, the sufferer should seek help to deal with the stress. As a first step, they can look to close friends, family, or clergy. Is there a support system of people they can trust with whom to discuss the problem? Talking with others about a stressful situation might alleviate some of the stress and with it the insomnia. If the situation is severe, sufferers should consider seeking help from a doctor, a counselor, a psychologist, or a social worker.
People seeking medical help for insomnia should not expect the doctor to ask about their sleep habits as part of the routine medical evaluation. This question simply does not come up often enough. The patient needs to bring the issue to the doctor’s attention.
The doctor should take the time to discuss the stressful situation and do an assessment to see whether the patient has clinically important depression or a medical problem. What the doctor should not do is write out a prescription for a sleeping pill or an antidepressant without further exploration of the insomnia.
Over the years many people have been referred to me for insomnia after being told by their doctors that they were depressed. Many of these patients were being treated with antidepressants, although some were not depressed. The saddest case I treated was a woman who had developed insomnia on a business trip in the mid-1970s and was started on medications for depression that she was still taking thirty years later. Tragically, the medication she was taking was not even a sleeping pill or an antidepressant; it was an antipsychotic medication that a doctor had prescribed to her in error. She had seen several doctors and had refilled the prescription more than a hundred times, but none of the doctors questioned why she was on this particular medication. The poor woman had been in a fog most of her adult life because of an error in her initial diagnosis and treatment.
When a doctor prescribes a pill to help a patient sleep, it is imperative that the patient ask what the pill is. Is it a sleeping pill or an antidepressant—and has it been approved for use for the treatment of insomnia? Sometimes doctors use medications to treat insomnia that have not been approved for use for insomnia by the U.S. Food and Drug Administration. Since insomnia is a common symptom of depression, antidepressants are frequently prescribed for sufferers. Patients who are prescribed an antidepressant need to ask whether the doctor has diagnosed them as depressed, and if so how long they will be on the medication, and what will constitute a cure.
Patients with insomnia that is not caused by depression and people who are depressed often share a number of common symptoms, such as loss of interest in their usual activities, depressed mood, lack of concentration, reduced memory, fatigue, sleep disturbance, loss of energy, lack of motivation, and irritability. But they usually differ dramatically when it comes to other symptoms. People who are depressed might also suffer from extremely low self-esteem; extreme and inappropriate guilt over past events, wrongdoings, or failings; a high degree of self-blame; and loss of appetite. They might consider suicide.
Patients should not be surprised or concerned if the medical practitioner refers them to another doctor—perhaps a psychiatrist or a psychologist. Most doctors have not received sufficient training on how to deal with the psychologically stressful situations that may lead to sleep disruption. Referral to a colleague is not a weakness on the doctor’s part, but rather a strength. It proves that the practitioner knows his or her limitations and can see when it is appropriate to refer the patient to a specialist.
So far in this chapter, I have discussed insomnia as a sleep complaint or a symptom for which sufferers can receive attention and treatment. Some people, however, have what scientists call “true” or “primary” insomnia, and its causes are still a mystery. For 5 to 10 percent of the total population of people who have insomnia, the cause remains unknown. The current theory is that people with this problem are born with an abnormal sleep-generating system.
Most people with this condition have had it all their lives. They frequently claim to have been unable to sleep since they were children; their parents say that they could not sleep even when they were babies. They fussed and had tremendous difficulty falling asleep and sleeping through the night.
People with primary insomnia sometimes have parents or siblings with the same sleep problem, which has led to the theory that this type of insomnia is or can be inherited in some people.
Because medical science does not know the cause of the problem, treatments can only address the symptoms. Some experts have reported good results when patients take a very low dose of antidepressant medication at bedtime. Some patients also do well with hypnotic drugs (sleeping pills).
Almost no one who reads this book has this problem. It is an extremely rare fatal condition that has been reported mostly in Italy (although a few cases have been reported elsewhere in the world, including countries in Europe and in North America) and has involved only a very small number of families. This disorder is caused by a rare genetic mutation which leads to the production of prions, which are made up of a chemical that is not a virus but behaves like one. The chemical takes over the machinery of the cells to make copies of itself. A study published in 2016 showed that neurons in parts of the brain that normally are involved in regulating sleep are destroyed. Prions also cause mad cow disease (bovine spongiform encephalopathy) and, in humans, Jakob-Creutzfeld disease. Jakob-Creutzfeld causes progressive damage to the nervous system until sufferers also eventually lose their ability to sleep. There is no successful treatment known at this time, and the disease is always fatal. But it is so rare that readers do not have to worry about it—I mention it only to show that insomnia can in extreme cases be associated with death.
When my patient described the night her insomnia started, her story sent a chill down my spine. She had been living in an apartment with her son, who was in his twenties, in a high-crime part of the city. On the night that would change her life forever, two burglars broke down the door to her apartment and killed her son with a knife before they fled. Afterward, the woman became obsessed with personal safety. She tried to stay awake as long as possible every night to make sure no one was breaking into her apartment. The times she woke up in a sweat from a nightmare were terrifying for her because her nightmare was always about the stabbing of her son. After a while, she developed a fear of falling asleep. The woman had posttraumatic stress disorder, which had been untreated for over twenty years. Her insomnia did not bother her much because remaining awake meant that she would not have the awful dreams. I knew I was out of my depth—my training is in internal medicine, pulmonary medicine, intensive care, and sleep disorders. I am not an expert in psychiatric conditions. This patient required expert specialized help. The solution for her was not going to be a sleeping pill but rather a detailed psychiatric assessment and treatment. I referred her to another doctor, and she has apparently done well. As we see in this woman’s case, insomnia is often not a disease but rather a symptom of some other disorder. To “cure” the insomnia, the patient or the doctor has to find out what else is going on.
Insomnia, while often distressing, is hard to treat because it has many different causes. Patients and doctors need to isolate the factors perpetuating the insomnia, as well as the comorbid conditions that may be present. Both might require treatment. One such factor is restless legs syndrome, a common cause of insomnia, but one that most doctors don’t know anything about.