What causes insomnia? While there is no one cut and dried reason why some people can’t sleep, most experts agree that insomnia is brought on by stress, anxiety, medications, and/or caffeine – among other things. Transient and short-term insomnia has many causes.
A reaction to change or stress is one of the most common causes of short-term and transient insomnia. This condition is sometimes referred to as adjustment sleep disorder.
The precipitating factor could be a major or traumatic event such as the following:
- An acute illness.
- Injury or surgery.
- The loss of a loved one.
- Job loss.
Temporary insomnia could also develop after a relatively minor event, including the following:
- Extremes in weather.
- An exam at school.
- Trouble at work.
In such cases, normal sleep almost always returns when the condition resolves, the individual recovers from the event, or the person becomes acclimated to the new situation. Treatment is needed if sleepiness interferes with functioning or if it continues for more than a few weeks.
Fluctuations in female hormones play a major role in what causes insomnia in women over their lifetimes. Such insomnia is most often temporary.
The hormone progesterone promotes sleep. Levels of this hormone plunge during menstruation, causing insomnia. When they rise during ovulation, women may become sleepier than usual.
During Pregnancy, the effects of changes in progesterone levels in the first and last trimester can disrupt normal sleep patterns and can be what causes insomnia for them.
Insomnia can be a major problem in the first phases of menopause, when hormones are fluctuating intensely. Insomnia during this period may be due to different factors that occur.
In some women, hot flashes, sweating, and a sense of anxiety can awaken women suddenly and frequently at night during the first months of menopause. In such women, hormone replacement therapy may be beneficial.
Insomnia may also be perpetuated by psychological distress provoked by this life passage. In most cases, insomnia is temporary. Cases of chronic insomnia in women after 50 are more likely to be due to other causes
In one study, 20% of adults reported that light, noise, and uncomfortable temperatures are what causes insomnia. Depending on the time of day too much or too little light can disrupt sleep. It is well known that a person’s biologic circadian clock is triggered by sunlight and very bright artificial light to maintain wakefulness. One study indicated that even dim artificial light may disrupt sleep.
Insufficient exposure to light during the day, as occurs in some disabled elderly patients who rarely venture outside, may also be linked with sleep disturbances. One study suggests that when a person is exposed to bright daylight, melatonin levels increases in response to darkness at night, which aids sleep.
Caffeine most commonly disrupts sleep. Nicotine can cause wakefulness. Quitting smoking can also cause transient insomnia. In fact, it has been suggested that if sleeping could be improved during withdrawal from smoking, then perhaps it would be easier to quit smoking.
Your partner’s sleep habits can also be what causes insomnia for you. In one 1999 survey, 17% of women and 5% of men reported that their partner’s sleep habits impaired their own sleep. Snoring can certainly be a factor in a partner’s insomnia. In fact, in the same survey 44% of men and 36% of women reported snoring a few nights a week and of those who snored, 19% could be heard through a closed door.
Insomnia is a side effect of many common medications, including over-the-counter preparations that contain caffeine. People who suspect their medications are causing them to lose sleep should check with a physician or pharmacist.
Chronic insomnia can also have deep seated roots. In many cases, it is unclear if chronic insomnia is a symptom of some physical or psychological condition or if it is a primary disorder of its own. In most instances, a collaboration of psychological and physical conditions causes the failure to sleep.
Psychophysiologic insomnia is the revolving door of sleeplessness:
- An episode of transient insomnia disrupts the person’s circadian rhythm.
- The patient begins to associate the bed not with rest and relaxation but with a struggle to sleep. A pattern of sleep failure emerges.
- Overtime, this event repeats, and bedtime becomes a source of anxiety. Once in bed, the patient broods over the inability to sleep and the loss of mental control. All attempts to sleep fail.
- After such a cycle is established, insomnia becomes a self-fulfilling prophecy that can persist indefinitely.
Sometimes anxiety and the inability to sleep dates back to childhood when parents used various threats to force their children into sleep for which they may not have been ready.
Pain and discomfort from an injury, illness, or disability can also impair sleep. Among the many medical problems that can cause insomnia are: allergies, arthritis, cancer, heart disease, gastro reflux disease, hypertension, asthma, and ADHD.
When people are in pain or sick, they general have medication to help them through the uncomfortable symptoms. Unfortunately, many of these medicines can also cause insomnia to onset or worsen. They include: nicotine, some anti-depressants, beta-blockers, etc.
A large percentage of chronic insomnia cases prove to have a psychological or even psychiatric basis. The disorders that most often cause insomnia are the following: anxiety, depression, and bipolar disorder.
It should be noted, however, that insomnia may cause emotional problems, and it is often unclear which condition has triggered the other, or if the two conditions, in fact, have a common source.
Anxiety accounts for almost 50 percent of the cases of chronic insomnia. Feeling uptight and anxious can keep you from relaxing enough to go to sleep.
A national survey by the US Department of Health and Human Services found that 47 percent of those reporting severe insomnia also reported feeling a high level of emotional distress. It could be that you become so tense and restless during a hard day at work that you don’t even expect to sleep well at night.
An estimated 10% to 15% of chronic insomnia cases result from substance abuse, especially alcohol, cocaine, and sedatives. One or two alcoholic drinks at dinner, for most people, poses little danger of alcoholism and may help reduce stress and initiate sleep.
Excess alcohol or alcohol used to promote sleep, however, tends to fragment sleep and cause wakefulness a few hours later. It also increases the risk for other sleep disorders, including sleep apnea and restless legs. Alcoholics often suffer insomnia during withdrawal and, in some cases, for several years during recovery.
A number of studies have reported that shift work throws off the body’s circadian rhythm and have suggested that such changes could lead to chronic insomnia. One study found that 53% of night-shift workers fall asleep on the job at least once a week, implying that their internal clocks do not adjust to unusual work times.
They are also at much higher risk than other workers for automobile accidents due to their drowsiness and may also have a higher risk for health problems in general. A Japanese study reporting on different aspects of insomnia found that excessive computer work was associated with all forms of insomnia. People who were over-involved with their work tended to have trouble falling asleep and they tended to awaken earlier than average.
Persistently high levels of stress hormones, particularly cortisol, may be key factors in many cases of chronic insomnia, particularly insomnia related to aging and psychiatric disorders. High levels of cortisol reduce REM sleep. Abnormal levels of other biologic factors may also a play a role in specific situations.
An imbalance in specific hormones important in sleep has been associated with aging and may be partly responsible for the higher incidence of insomnia in older people. Older people experience higher levels of major stress hormones (cortisol and adrenocorticotropin) during the night. Why?
Normal aging is associated with a blunting of regular, cyclical surges of growth hormone. This hormone, which is normally secreted in the late night, is associated not only with growth but with deep, slow-wave sleep. Older people generally have less slow-wave sleep.
Melatonin levels, the hormone secreted by the pineal gland are lower, in older people. Some research suggests that elderly people may have lower levels in general simply because many stay mostly indoors and out of normal sunlight.
In spite of such observations a number of studies report no higher risk for insomnia in older adults who have no accompanying mental or physical problems.
There may also be a genetic link to what causes insomnia. Sleep problems seem to run in families; approximately 35% of people with insomnia have a positive family history, with the mother being the most commonly affected family member. Still, because so many factors are involved in insomnia, a genetic component is difficult to define.
So we’ve seen that there can be many reasons to what causes insomnia and why some people simply cannot sleep.