Insomnia

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Insomnia is a symptom of a sleeping disorder characterized by persistent difficulty falling asleep or staying asleep despite the opportunity. It is typically followed by functional impairment while awake. Insomniacs have been known to complain about being unable to close their eyes or "rest their mind" for more than a few minutes at a time. Both organic and non-organic insomnia constitute a sleep disorder.^[1][2]

According to the U.S. Department of Health and Human Services in year 2007, approximately 64 million Americans suffer from insomnia each year.^[3] Insomnia occurs 1.4 times more commonly in women than in men.^[4]

Types of Insomnia

Although there are several different degrees of insomnia, about three types of insomnia have been clearly identified: transient, acute, and chronic.

1. Transient insomnia lasts from days to weeks. It can be caused by another disorder, by changes in the sleep environment, by the timing of sleep, or by stress. Its consequences - sleepiness and impaired psychomotor performance - are similar to those of sleep deprivation.^[5] If this form of insomnia continues to occur from time to time, the insomnia is classified as intermittent.^{citation needed}
2. Acute insomnia is the inability to consistently sleep well for a period of between three weeks to six months.^[6]
3. Chronic insomnia lasts for years and years at a time. It can be caused by another disorder, or it can be a primary disorder. Its effects can vary according to its causes. They might include sleepiness, muscular fatigue, hallucinations, and/or mental fatigue; but people with chronic insomnia often show increased alertness. Some people that live with this disorder see things as though they were happening in slow motion, whereas moving objects seem to blend together.^[5]

Patterns of Insomnia

The pattern of insomnia often is related to the etiology.^[7]

1. Onset insomnia - difficulty falling asleep at the beginning of the night, often associated with anxiety disorders.
2. Middle-of-the-Night Insomnia - Insomnia characterized by difficulty returning to sleep after awakening in the middle of the night or waking too early in the morning. Also referred to as nocturnal awakenings. Encompasses middle and terminal insomnia.
3. Middle insomnia - waking during the middle of the night, difficulty maintaining sleep. Often associated with pain syndromes or medical illness.
4. Terminal (or late) insomnia - early morning waking. Characteristic of clinical depression.

Causes

Insomnia can be caused by:

• Psychoactive drugs or stimulants, including certain medications, herbs, caffeine, cocaine, ephedrine, amphetamines, methylphenidate, MDMA, methamphetamine and modafinil
• Hormone shifts such as those that precede menstruation and those during menopause
• Life problems like fear, stress, anxiety, emotional or mental tension, work problems, financial stress, unsatisfactory sex life
• Mental disorders such as clinical depression, schizophrenia, bipolar disorder, general anxiety disorder
• Disturbances of the circadian rhythm, such as shift work and jet lag, can cause an inability to sleep at some times of the day and excessive sleepiness at other times of the day. Jet lag is seen in people who travel through multiple time zones, as the time relative to the rising and setting of the sun no longer coincides with the body's internal concept of it. The insomnia experienced by shift workers is also a circadian rhythm sleep disorder.
• Certain neurological disorders, brain lesions, or a history of traumatic brain injury
• Medical conditions such as hyperthyroidism and Wilson's syndrome
• Abuse of over-the counter or prescription sleep aids can produce rebound insomnia
• Poor sleep hygiene
• Parasomnia, which includes a number of disruptive sleep events including nightmares, sleepwalking, violent behavior while sleeping, and REM behavior disorder, in which a person moves his/her physical body in response to events within his/her dreams
• The full moon lunar phase^[8]
• A rare genetic condition can cause a prion-based, permanent and eventually fatal form of insomnia called fatal familial insomnia

A common misperception is that the amount of sleep a person requires decreases as he or she ages. The ability to sleep for long periods, rather than the need for sleep, appears to be lost as people get older. Some elderly insomniacs toss and turn in bed and occasionally fall off the bed at night, diminishing the amount of sleep they receive.^[9]

An overactive mind or physical pain may also be causes. Finding the underlying cause of insomnia is usually necessary to cure it. Insomnia can be common after the loss of a loved one, even years or decades after the death, if they have not gone through the grieving process. Overall, however, symptoms and the degree of severity affects different people differently, depending on their mental health, physical condition, and attitude or personality.

Diagnosis

Patients with delayed sleep phase syndrome are often mis-diagnosed with insomnia. If the patient has trouble getting to sleep, but has normal sleep architecture once asleep, a circadian rhythm disorder is a more likely cause.

Insomnia Versus Poor Sleep Quality

Poor sleep quality can occur as a result of sleep apnea or clinical depression. Poor sleep quality is caused by the individual not reaching stage 4 or delta sleep which has restorative properties. There are, however, people who are unable to achieve stage 4 sleep due to brain damage who still lead perfectly normal lives.

• Sleep apnea is a condition that occurs when a sleeping person's breathing is interrupted, thus interrupting the normal sleep cycle. With the obstructive form of the condition, some part of the sleeper's respiratory tract loses muscle tone and partially collapses. People with obstructive sleep apnea often do not remember awakening or having difficulty breathing, but they complain of excessive sleepiness during the day. Central sleep apnea interrupts the normal breathing stimulus of the central nervous system, and the individual must actually wake up to resume breathing. This form of apnea is often related to a cerebral vascular condition, congestive heart failure, and premature aging.

Major depression leads to alterations in the function of the hypothalamic-pituitary-adrenal axis, causing excessive release of cortisol which can lead to poor sleep quality.

Nocturnal polyuria or excessive nighttime urination can be very disturbing to sleep.^[10] Nocturnal polyuria can be nephrogenic (related to kidney disease) or it may be due to prostate enlargement or hormonal influences.^{citation needed} Deficiencies in vasopressin, which is either caused by a pituitary problem or by insensitivity of the kidney to the effects of vasopressin, can lead to nocturnal polyuria.^{citation needed} Excessive thirst or the use of diuretics can also cause these symptoms.^{citation needed}

Treatment for Insomnia

In many cases, insomnia is caused by another disease or psychological problem. In this case, medical or psychological help may be useful.

Medications

Many insomniacs rely on sleeping tablets and other sedatives to get rest. All sedative drugs have the potential of causing psychological dependence where the individual cannot psychologically accept that they can sleep without drugs. Certain classes of sedatives such as benzodiazepines and newer nonbenzodiazepine drugs can also cause physical dependence which manifests in withdrawal symptoms if the drug is not carefully titrated down.

In comparing the options, a systematic review found that benzodiazepines and nonbenzodiazepines have similar efficacy which was insignificantly more than for antidepressants.^[11] Benzodiazepines had an insignificant tendency for more adverse drug reactions.^[11]

Benzodiazepines

Main article: Benzodiazepine

The most commonly used class of hypnotics prescribed for insomnia are the benzodiazepines. Benzodiazepines bind unselectively to the GABA_A receptor.^[11] This includes drugs such as temazepam, flunitrazepam, triazolam, flurazepam, nitrazepam and midazolam. These medications can develop tolerance and dependence, especially after consistent usage over long periods of time.

Non-benzodiazepines

Main article: Nonbenzodiazepine

Nonbenzodiazepine prescription drugs, such as Ambien (zolpidem), Sonata (zopiclone) and Lunesta (eszopiclone), are more selective for the GABA_A receptor^[11] and may have a cleaner side effect profile than the older benzodiazepines; however, there are controversies over whether these non-benzodiazepine drugs are superior to benzodiazepines. These drugs appear to cause both psychological dependence and physical dependence though less than traditional benzodiazepines, and can also cause the same memory and cognitive disturbances along with morning sedation. They belong to the new category of medications called sedative-hypnotics.

Antidepressants

Main article: Antidepressants

Some older antidepressants such as amitriptyline, doxepin, mirtazapine, and trazodone may have a sedative effect, and are prescribed off label to treat insomnia. The major drawback of these drugs is that they have antihistaminergic, anticholinergic and antiadrenergic properties which can lead to many side effects. Some also alter sleep architecture. As with many benzodiazepines, the use of antidepressants in the treatment of insomnia can lead to physical dependence; withdrawal may induce rebound insomnia and actually further complicate matters in the long-term.

Melatonin

Melatonin has proved effective for some insomniacs in regulating the sleep/waking cycle, but lacks definitive data regarding efficacy in the treatment of insomnia. Melatonin agonists, including Ramelteon (Rozerem), seem to lack the potential for abuse and dependence. This class of drugs has a relatively mild side effect profile and lower likelihood of causing morning sedation. Natural substances such as 5-HTP and L-Tryptophan have been said to fortify the serotonin -> melatonin pathway and aid people with various sleep disorders including insomnia.^[12]

Antihistamines

The antihistamine Benedryl (diphenhydramine) is widely used in nonprescription sleep aids such as Tylenol PM, with a 50 mg recommended dose mandated by the FDA. In the United Kingdom, Australia, New Zealand, South Africa, and other countries, a 50 to 100 mg recommended dose is permitted. While it is available over the counter, the effectiveness of these agents may decrease over time and the incidence of next-day sedation is higher than for most of the newer prescription drugs. Dependence does not seem to be an issue with this class of drugs.

Periactic (Cyproheptadine) is a useful alternative to benzodiazepine hypnotics in the treatment of insomnia. Cyproheptadine may be superior to benzodiazepines in the treatment of insomnia because cyproheptadine enhances sleep quality and quantity whereas benzodiazepines tend to decrease sleep quality.^[13]

Atypical Antipsychotics

Low doses of certain atypical antipsychotics such as quetiapine (Seroquel) are also prescribed for their sedative effect but the danger of neurological and cognitive side effects make these drugs a poor choice to treat insomnia. Over time, Seroquel may lose it's ability to produce sedation.

Other Substances

Some insomniacs use herbs such as valerian, chamomile, lavender, hops, and passion-flower. Valerian has undergone multiple studies and appears to be modestly effective.^[14][15][16] Cannabis has also been suggested as a very effective treatment for insomnia.^[17]

Though alcohol may have sedative properties, the REM sleep suppressing effects of the drug prevent restful, quality sleep.^{citation needed} Also, middle-of-the-night awakenings due to polyuria or other effects from alcohol consumption are common, and hangovers can also lead to morning grogginess.

Insomnia may be a symptom of magnesium deficiency, or lower magnesium levels. A healthy diet containing magnesium, can help to improve sleep in individuals without an adequate intake of magnesium.^[18]

Other reports cite the use of an elixir of cider vinegar and honey but the evidence for this is only anecdotal.^[19]

Cognitive behavior therapy

Recent research has shown that cognitive behavior therapy can be more effective than medication in controlling insomnia.^[20] In this therapy, patients are taught improved sleep habits and relieved of counter-productive assumptions about sleep.^[20]

Complementary and Alternative medicine

Some traditional and anecdotal remedies for insomnia include: drinking warm milk before bedtime, taking a warm bath, exercising vigorously for half an hour in the afternoon, eating a large lunch and then having only a light evening meal at least three hours before bed, avoiding mentally stimulating activities in the evening hours, going to bed at a reasonable hour and getting up early, and avoiding exposing the eyes to too much light, especially blue light, a few hours before bedtime. Initial treatment of insomnia may include the rules of Sleep Hygiene

Using aromatherapy, including jasmine oil, lavender oil, Mahabhringaraj and other relaxing essential oils, may also help induce a state of restfulness. Many believe that listening to slow paced music will help insomniacs fall asleep. ^[21]

The more relaxed a person is, the greater the likelihood of getting a good night's sleep. Relaxation techniques such as meditation have been shown to help people sleep. Such techniques can lower stress levels from both the mind and body, which leads to a deeper, more restful sleep.^{citation needed}

Traditional Chinese medicine has included treatment for insomnia. A typical approach may utilize acupuncture, dietary and lifestyle analysis, herbology and other techniques, with the goal of resolving the problem at a subtle level.

In the Buddhist tradition, people suffering from insomnia or nightmares may be advised to meditate on "loving-kindness", or metta. This practice of generating a feeling of love and goodwill is claimed to have a soothing and calming effect on the mind and body.^[22] This is claimed to stem partly from the creation of relaxing positive thoughts and feelings, and partly from the pacification of negative ones. In the Mettā (Mettanisamsa) Sutta,^[23] Siddhartha Gautama, the Buddha, tells the gathered monks that easeful sleep is one benefit of this form of meditation.

Hypnotherapy, self hypnosis and guided imagery can be effective in not only falling asleep and staying asleep; they can also help to develop good sleeping habits over time. Visualizing can be effective in taking the mind away from present day anxieties and towards a more relaxing place. Binaural Beats can help people fall asleep faster using special sounds.

See also

• Sleep
• Sleep disorder
• Fatal familial insomnia
• Sleep deprivation
• Delayed sleep phase disorder
• Actigraphy

References