Insomnia is defined as difficulty initiating or maintaining sleep, or both, despite adequate opportunity and time to sleep, leading to impaired daytime functioning. Insomnia may be due to poor quality or quantity of sleep.
Insomnia is very common and occurs in 30% to 50% of the general population. Approximately 10% of the population may suffer from chronic (long-standing) insomnia.
Insomnia affects people of all ages including children, although it is more common in adults and its frequency increases with age. In general, women are affected more frequently than men.
Insomnia may be divided into three classes based on the duration of symptoms.
- Insomnia lasting one week or less may be termedtransient insomnia;
- short-term insomnia lasts more than one week but resolves in less than three weeks;
- long-term or chronic insomnia lasts more than three weeks.
Insomnia can also be classified based on the underlying reasons for insomnia such as sleep hygiene, medical conditions, sleep disorders, stress factors, and so on.
It is important to make a distinction between insomnia and other similar terminology; short duration sleep and sleep deprivation.
- Short duration sleep may be normal in some individuals who may require less time for sleep without feeling daytime impairment, the central symptom in the definition of insomnia.
- In insomnia, adequate time and opportunity for sleep is available, whereas in sleep deprivation, lack of sleep is due to lack of opportunity or time to sleep because of voluntary or intentional avoidance of sleep.
Impairment of daytime functioning is the defining and the most common symptom of insomnia.
Other common symptoms include:
- daytime fatigue,
- daytime sleepiness,
- mood changes,
- poor attention and concentration,
- lack of energy,
- poor social function,
- increased errors and mistakes.
In general, insomnia related to transient situational factors resolves spontaneously when the provoking factor is removed or corrected. However, medical evaluation by a doctor may be necessary if the insomnia persists or it is thought to be related to a medical or a psychiatric condition.
There are also specialized doctors who evaluate and treat insomnia and other sleep disorders. Sleep apnea may be evaluated and treated by pulmonologists (lung doctors) who have specialized in sleep disorders. Other doctors who evaluate and treat sleep disorders are neurologists with a specialty in sleep disorders.
Evaluation and diagnosis of insomnia may start with a thorough medical and psychiatric patient history taken by the physician. As mentioned above, many medical and psychiatric conditions can be responsible for insomnia.
A general physical examination to assess for any abnormal findings is also important, including assessment of mental status and neurological function; heart, lung and abdominal exam; ear, nose and throat exam; and measurement of the neck circumference and waist size. Assessment of routine medications and use of any illegal drugs, alcohol, tobacco, or caffeine is also an important part of the medical history. Any laboratory or blood work pertinent to these conditions can also be a part of the assessment.
The patient's family members and bed partners also need to be interviewed to ask about the patient's sleep patterns, snoring, or movements during sleep.
Specific questions regarding sleep habits and patterns are also a vital part of the assessment.
A sleep history focuses on:
- duration of sleep,
- time of sleep,
- time to fall sleep,
- number and duration of awakenings,
- time of final awakening in the morning, and time and length of any daytime naps.
Sleep logs or diaries may be used for this purpose to record these parameters on a daily basis for more accurate assessment of sleep patterns.
Sleep history also typically includes questions about possible symptoms associated with insomnia. The physician may ask about daytime functioning, fatigue, concentration and attention problems, naps, and other common symptoms of insomnia.
Other diagnostic tests may be done as part of the evaluation for insomnia, although they may not be necessary in all patients with insomnia.
Polysomnography is a test that is done in sleep centers if conditions such as sleep apnea are suspected. In this test, the person will be required to spend a full night at the sleep center while being monitored for heart rate, brain waves, respirations, movements, oxygen levels, and other parameters while they are sleeping.
The data is then analyzed by a specially trained physician to diagnose or rule out sleep apnea. Actigraphy is another more objective test that may be performed in certain situations but is not routinely a part of the evaluation for insomnia.
Insomnia may have many causes and, as described earlier, it can be classified based upon the underlying cause.
Situational and stress factors leading to insomnia may include:
- jet lag,
- physical discomfort (hot, cold, lighting, noise, unfamiliar surroundings),
- working different shifts,
- stressful life situations (divorce or separation, death of a loved one, losing a job, preparing for an examination),
- illicit drug use,
- cigarette smoking,
- caffeine intake prior to going to bed,
- alcohol intoxication or withdrawal,
- certain medications.
Most of these factors may be short-term and transient, and therefore insomnia may resolve when the underlying factor is removed or corrected.
Sleep hygiene can play an important role in insomnia.
Poor sleep hygiene includes physical factors such as:
- using the bedroom for things other than sleeping,
- eating or exercising prior to sleep,
- going to bed hungry,
- sleeping in a room with too much noise or lighting,
- doing work in bed.
Medical and psychiatric conditions
Medical and psychiatric conditions may also contribute to insomnia.
Some of these common medical conditions may include:
- breathing problems from chronic heart or lung disease (asthma, chronic obstructive pulmonary disease (COPD),
- congestive heart failure,
- obstructive sleep apnea,
- acid reflux,
- urinary problems (frequent urination, urinary incontinence),
- chronic pain,
- Parkinson's disease,
Common psychiatric problems can be responsible for insomnia including:
Some common physiologic conditions can lead to insomnia such as:
- menstrual cycle,
Other causes of insomnia may be related to sleep disorders including:
- sleep walking,
- sleep apnea,
- restless leg syndrome (creeping sensations in the leg during sleep, relieved by leg movement),
- periodic limb movement disorder (involuntary repeated leg movement during sleep),
- circadian sleep disturbance (unusual sleep time due to disturbed biological clock).
The treatment of insomnia depends largely on the cause of the problem. In cases where an obvious situational factor is responsible for the insomnia, correcting or removing the cause generally cures the insomnia. For example, if insomnia is related to a transient stressful situation, such as jet lag or an upcoming examination, then insomnia will be cured when the situation resolves.
Generally speaking, the treatment of insomnia can be divided into non-medical or behavioral approaches and medical therapy. Both approaches are necessary to successfully treat insomnia, and combinations of these approaches may be more effective than either approach alone.
When insomnia is related to a known medical or psychiatric condition, then appropriate treatment of that condition is in the forefront of therapy for insomnia in addition to the specific therapy for insomnia itself. Without adequately addressing the underlying cause, insomnia will likely go on despite taking aggressive measures to treat it with both medical and non-medical therapies.
There are several recommended techniques used in treating people with insomnia. These are non-medical strategies and are generally advised to be practiced at home in combination with other remedies for insomnia, such as medical treatments for insomnia and treatment for any underlying medical or psychiatric disorders.
Some of the most important of these behavioral techniques are sleep hygiene, stimulus control, relaxation techniques, and sleep restriction.
The main classes of medications used to treat insomnia are the sedatives and hypnotics, such as the benzodiazepines and the non-benzodiazepine sedatives.
Several medications in the benzodiazepine class have been used successfully for the treatment of insomnia, and the most common ones include:
- quazepam (Doral),
- triazolam (Halcion),
- estazolam (ProSom),
- temazepam (Restoril),
- flurazepam (Dalmane),
- lorazepam (Ativan).
Another common benzodiazepine, diazepam(Valium), is typically not used to treat insomnia due to its longer sedative effects.
Non-benzodiazepine sedatives are also used commonly for the treatment of insomnia and include most of the newer drugs.
Some of the most common ones are:
- zaleplon (Sonata),
- zolpidem (Ambien or Ambien CR, Zolpimist),
- eszopiclone (Lunesta).
Melatonin, a chemical released from the brain which induces sleep, has been tried in supplement form for treatment of insomnia as well. It has been generally ineffective in treating common types of insomnia, except in specific situations in patients with known low levels of melatonin. Melatonin may be purchased over-the-counter (without a prescription).
Ramelteon (Rozerem), which is an insomnia drug that acts by mimicking the action of melatonin, is a newer drug. It has been used effectively in certain group of patients with insomnia.
There are also other medications that are not in the sedative or hypnotic classes, which have been used in the treatment of insomnia. Sedativeantihistamines, diphenhydramine (Benadryl) have been used as sleep aids because of their sedative effects; however, this is not a recommended use of these or other similar drugs due to many side effects and long-term drowsiness the following day.
Some anti-depressants [for example, trazodone (Desyrel), amitriptyline (Elavil, Endep), doxepin (Sinequan, Adapin)] can be used effectively to treat insomnia in patients who also may suffer from depression. Some anti-psychotics have been used to treat insomnia, although their routine use for this purpose is generally not recommended.
A doctor or sleep specialist is the best person to discuss these different medications, and to decide which one may be the best for each specific individual. Many of these drugs have a potential for abuse and addiction and need to be used with caution. None of these medications may be taken without the supervision of the prescribing physician.