Articles

Insomnia, Sleep Disorders

Introduction

Insomnia is a chronic inability to obtain or sustain sleep. While everyone occasionally experiences sleeplessness, chronic insomnia is an ongoing, often debilitating condition. After a night of inadequate sleep, those with insomnia report impaired mental and physical abilities, diminished memory, reduced alertness, and impaired reaction time. (1) Chronic lack of sleep threatens the well being, productivity, and safety of millions of Americans. Insomnia is not a disease but a condition associated with a number of physical and emotional disorders. The incidence of insomnia is higher among people with chronic illnesses, such as hyperthyroidism, renal insufficiency, multiple sclerosis, and Alzheimer’s disease. Pregnancy, alcohol intake, stress, and depression are also leading causes of insomnia.

What determines sleep remains somewhat a mystery. Four stages of sleep have been identified by studies of brain wave patterns. Stage 1, the lightest sleep, is accompanied by muscle relaxation and a slowing of the heart rate. During stage 2 sleep, there is an increase in heart rate and eye movements, known as REM (rapid eye movements). During REM sleep, there is increased autonomic nervous system activity indicated by rapid breathing and increased stomach acid secretion. Muscle tone during REM sleep is inactive. Presumably, this is the period when dreaming takes place. During deep sleep (stages 3 and 4), there is no dreaming. During the sleep period, a person normally cycles from stage 1 to stage 4 in about 90 minutes. (2) Waking after a sleep cycle is complete is common among the elderly and small children.

Statistic

National Sleep Foundation, 2000.

    Nearly two-thirds of adults in the U.S. (62%) experienced a sleep problem a few nights per week or more during the past year. Specifically, more than one-half of the adults surveyed (58%) report having experienced one or more symptoms of insomnia a few nights per week or more within the past year. One-third (33%) of adults say they get fewer than 6.5 hours of sleep per night during the workweek.

Signs and Symptoms

[span class=alert]The following list does not insure the presence of this health condition. Please see the text and your healthcare professional for more information.[/span]

The most common type of insomnia is sleep-onset insomnia, which is characterized by a difficulty falling asleep. Typically, sleep occurs within about 20 minutes. For those with sleep-onset insomnia, it may take hours before sleep is obtained. Strangely, sleep typically comes around 3:00 AM for many suffering this type of insomnia. (3) This may be related to an alteration in body temperature phases. It has been shown that insomniacs have temperature rhythms that are about 2.5 hours later than normal sleepers. (4)

Early morning waking insomnia (terminal insomnia) is characterized by normal sleep onset with early awakening. Although described as "early morning" waking, the actual hour depends on the initial bedtime and the circadian rhythm of the individual. Once awake, the terminal insomniac can not go back to sleep. Early morning waking is a classic sign of depression. (5) It is thought that this type of insomnia is also related to an early rise in body temperature. A recent study among the elderly with sleep disorders demonstrated that elevated core body temperature is associated with night waking. (6)

Sleep-onset insomnia

    Difficulty falling asleep for hours Body temperature rhythms that are about 2.5 hours later than normal sleepers Disturbance in daytime functioning

Terminal insomnia

    Normal sleep onset with early awakening Once awake, can not go back to sleep Depression may be present Disturbance in daytime functioning

Treatment Options

Conventional

Conventional treatment of insomnia includes the use of antihistamines, sedative hypnotic drugs (benzodiazepines), antidepressants, or a combination of the above. In 1999, the FDA approved a new prescription drug, zolpidem, for the short-term management of insomnia in adults.

    Benzodiazepines (estazolam, lorazepam, quazepam) have been prescribed since the 1960's for the management of anxiety. Benzodiazepine receptors are found in the limbic system and cerebral cortex, two brain centers associated with primitive emotional behavior. Benzodiazepines work by increasing the activity of the neurotransmitter (GABA), which reduces neuronal stimulation. The popularity of this class of drugs stems from its low toxicity. Lethal overdoses of benzodiazepines are rare. Major side effects include daytime sedation, dizziness, ataxia, and headaches. Tolerance and dependency are not unusual for some drugs in this class. Antihistamines (diphenhydramine, hydroxyzine) offer a short-term alternative for temporary insomnia. Antihistamines, used to treat allergic reactions, also cause drowsiness. They are relatively mild with few adverse effects. Some side effects may include dry mouth and tremor. Many antihistamines are available over the counter, making them readily available. Antidepressants such as the tricyclic agent amitriptyline and some selective serotonin re-uptake inhibitors (SSRIs) such as fluoxetine, sertraline, paroxetine, fluvoxamine, and citalopram may be effective in treating insomnia related to depression. Side effects of antidepressants may include dry mouth, constipation, urinary retention, bone-marrow depression, and decreased libido. Zolpidem is the newest prescription medication available for the treatment of insomnia. Zolpidem is a non-benzodiazepine hypnotic (a pyrazolopyrimidine compound) with effects similar to drugs in the benzodiazepine class. Although zolpidem produces some psychomotor and memory impairment initially, it appears to have no residual effects the following day. (7) This is due to its extremely short half-life of approximately one hour. (8) Zolpidem also has a very short onset, so it can be taken as needed at bedtime. Zolpidem appears to be effective for both sleep-onset insomnia and early-morning waking. The most common adverse effects are nausea, dizziness, and drowsiness. During a clinical trial of the drug, there were no indications of rebound insomnia or withdrawal after discontinuing the drug. (9)

Nutritional Supplementation


Melatonin

Melatonin is the sleep trigger that regulates the body’s sleep/wake cycles. It has been suggested that patients with specific neurological disorders may have changes in their melatonin secretion that causes sleep disorders. A group of psychiatrists reported the following: "It is both striking and in some ways not surprising that the majority of patients with phase delay syndrome described in our research studies have been misdiagnosed as having depression." (10)

Melatonin reportedly is effective in improving sleeping patterns in phase shift workers and people who have trouble sleeping due to what is called delayed sleep phase syndrome (DSPS). (11) , (12) The studies on melatonin and jet lag are mixed. (13) , (14)

Melatonin products are available as regular tablets (or capsules), sublingual tablets, and timed-release tablets. Sublingual tablets, which are fast acting, work best for people who have difficulty falling asleep. Timed-release products work better for people who wake up during the night. Some take both, a sublingual to get to sleep and a timed-released tablet to help them have a better chance of sleeping through the night.


5-Hydroxytryptophan (5-HTP)

5-HTP (5-Hydroxytryptophan) is the immediate precursor to serotonin, which is converted into melatonin in the brain. Thus, 5-HTP is a product that can be used to improve sleep patterns. (15) Animal studies report that 5-HTP is significantly more effective than tryptophan at inducing dose-dependent changes in sleep-wake activity. (16) There are a few reasons why 5-HTP is considered superior to tryptophan for inducing sleep. First, some of the ingested tryptophan gets metabolized in other biochemical pathways, so part of it is "lost." Also, 5-HTP is more effective at crossing the blood-brain barrier than tryptophan because it doesn’t have to compete with other amino acids for transport into the brain.

Herbal Supplementation


Kava

South Pacific natives have used kava for centuries. The root is used in the preparation of a recreational beverage known by a variety of local names (kava, yaqona, awa) and occupies a prominent position in the social, ceremonial, and daily life of Pacific island peoples as coffee or tea does in the Western cultures. In European phytomedicine, kava has long been used as a safe, effective treatment for mild anxiety states, nervous tension, muscular tension, and mild insomnia. (17) , (18) Researchers suggest after a multicenter, randomized, placebo-controlled, double-blind clinical trial that kava may be effective and safe when used for sleep disturbances associated with anxiety disorders. (19) Studies have reported that kava preparations compare favorably to benzodiazepines in controlling symptoms of anxiety and minor depression, while increasing vigilance, sociability, memory, and reaction time. (20) , (21) Reports are conflicting as to whether kava’s anti-anxiety actions are GABA mediated. (22) , (23) Kavalactones appear to act on the limbic system, in particular the amygdala complex, the primitive part of the brain that is the center of the emotional being and basic survival functions. (24) It is thought that kava may promote relaxation, sleep, and rest by altering the way in which the limbic system modulates emotional processes. Tolerance does not seem to develop with kava use. (25) , (26)


Passionflower

Passionflower, or maypop, is a common roadside vine in many areas of the United States. Passionflower has been reported to have sedative, hypnotic, antispasmodic, and anodyne properties. It has traditionally been used for neuralgia, generalized seizures, hysteria, nervous tachycardia, spasmodic asthma, and specifically for insomnia. (27) The bioactive constituents maltol and ethylmaltol have been reported to have CNS sedation, anticonvulsant activity (high doses), and a reduction in spontaneous motor activity (low doses) in laboratory animals. (28) Passionflower extracts have been reported to reduce locomotor activity, prolong sleeping time, raise the nociceptive threshold, and produce an anxiolytic effect in laboratory animals. (29) In humans, passionflower has been reported effective when used in combination with other sedative and anti-anxiety herbs such as valerian, making it beneficial in conditions such as hyperthyroidism, where CNS stimulation occurs. (30) These effects may be due to synergism and also due to the potential binding of passionflower constituents to benzodiazepine receptors in vivo. (31) , (32)


Valerian

Valerian has long been used as an agent to soothe the nervous system in response to stress. It has been reported that valerian helps improve sleep quality. (33) , (34) , (35) The usefulness of valerian is reported to be due to several principal components, including valepotriates, valeric acid, and pungent oils, which have a sedative effect on the central nervous system, as well as a relaxing effect on the smooth muscles of the GI tract. (36) , (37) It is felt that both valepotriates and valeric acid bind to receptor sites similar to the benzodiazepines. (38) Valerian’s constituents reportedly influence gamma aminobutyric acid (GABA) activity through affinity for receptors in the brain. (39) Valerian does not seem to produce the morning drug hangover effect as seen with some benzodiazepines. (40) Studies have found that valerian extract when administered to healthy volunteers was not mood-altering or did not have psychomotor/cognitive effects. Because of fewer side effects, valerian could prove to be a less troublesome alternative to drugs in the treatment of insomnia. (41) , (42)


Chamomile

Chamomile has been used as a medicinal herb for centuries. It is most frequently used as a mild sedative for individuals with minor anxiety or nervousness. (43) It reportedly does not induce drowsiness or impair motor activity. Chamomile has also been used to soothe digestive upset and is considered a carminative (anti-gas) agent. (44) Chamomile has been used topically for various conditions such as acne, infections, burns, and wounds. (45) Apigenin has been reported to be a ligand for the central benzodiazepine receptors, exerting anxiolytic and slight sedative effects, but not being anticonvulsant or myorelaxant. (46)


Hops

Hops have been used since the Roman times in brewing and as a traditional nerve and sedative tonic. Hops are stated to possess sedative, hypnotic, antispasmodic, and topical bactericidal properties. (47) Traditional uses of hops include neuralgia, insomnia, excitability, topically for skin ulcerations, and primarily for restlessness associated with nervous tension. (48) The sedative effect of hops is not fully understood. Early research demonstrating the sedative action of hops in laboratory animals produced conflicting results. (49) Human studies of the sedative action generally refer to hops being used in combinations with one or more additional herbs. In laboratory studies, hops has been reported to increase the sleeping time induced by pentobarbital. (50) Hops was reported to improve sleep disturbances when given in combination with other sedative herbs such as valerian root and passionflower. (51) The constituent 2-methyl-3-buen-2-ol was found to have a central nervous system depressant activity when given intraperitoneally in laboratory animals at high dosages. Even though only a small amount of this compound is usually present in hops products, it is formed in vivo through metabolism of the a-bitter acids humulone and lupulone, which may explain the sedative action of hops. (52) , (53)

Homeopathic

Coffea cruda

Typical Dosage: 6X or 6C, 30X or 30CNervous excitement that keeps the mind active; Often awaken about 3:00AM and cannot go back to sleep

Ignatia amara

Typical Dosage: 6X or 6C, 30X or 30CIntellectual strain

Lycopodium clavatum

Typical Dosage: 6X or 6C, 30X or 30CCannot stop mind from thinking about day’s events

Nux vomica

Typical Dosage: 6X or 6C, 30X or 30CLight, disturbed sleep with bad dreams, often due to overexertion or overindulgence in food and drink; Always feel as if more sleep is needed

Diet & Lifestyle

    Avoid caffeine and alcohol in the afternoon and evening. Some people report that small amounts of caffeine can keep them awake, even 8-10 hours after consumption. Maintain a consistent bedtime routine. Go to bed and wake up at the same time every day, even on weekends. Exercise during the day can improve sleep at night. Increase your body temperature slightly before bed in a warm bath or shower. The subsequent decline can help induce and maintain sleep. Try to stop work or doing tasks that keep the mind active earlier in the evening. Avoid television before bed. The lights and sounds can over-stimulate the nervous system. If the insomnia is stress induced, try and learn stress reduction techniques. This is different for many, but exercise, yoga, tai chi, or any activity that will bring joy and calmness is a big step in the right direction. Some people who wake up during the middle of the night do so because of hypoglycemia. Consuming a small snack just before bedtime helps to stabilize blood sugar levels throughout the night. Ideally, snacks should consist of complex carbohydrates, along with a little fat and protein. This allows for more of a timed-release breakdown and release of energy into the body.

Clinical Lab Assessment

Some of the following laboratory testing can provide information necessary for diagnosis and treatment. In addition, the tests listed may also give insight to functional metabolism and functional nutrient status in the body.

Adrenal Function Profiles

Stress activates the HPA axis and has impact on the immune system, particularly through the adrenal hormones. In assessing the HPA axis, adrenal functional abnormalities are relatively simple to identify and address (e.g., when compared to hypothalamic dysregulation or pituitary imbalance).

Insulin and Cortisol: The interactions of these hormones in the sleep-wake cycle have been found to be significant. (54) Monitoring may prove useful.

Melatonin

Melatonin an antioxidant, is considered important in the healthy sleep cycle. (55)

Amino Acids

Deficiencies or imbalances in amino acids can indicate fundamental reasons for numerous disorders. Amino acid malabsorption syndrome or imbalanced amino patterns reflect abnormal organ and glandular processes that have critical bearing on optimal function. Several amino acids have impact on healthy sleep patterns. (56) , (57) , (58) , (59)

References

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