Obstructive sleep apnea is serious, currently underdiagnosed, and associated with increased risk of hypertension, stroke, myocardial infarction, and death. Most persons with obstructive sleep apnea snore, and the condition is particularly common in overweight persons.
Episodes of apnea and hypopnea are defined by a clear reduction in airflow or tidal volume, often accompanied by a decrease in oxygen saturation and terminated by an arousal (an interval of three seconds or longer in which the electroencephalographic pattern indicates that the patient is awake). In addition, breathing and limb movements and an electrocardiographic lead are monitored.
The main cause of restless legs syndrome (RLS) is unknown. Researchers are investigating neurologic (nervous system) problems that may arise either in the spinal cord or the brain. One current theory suggests that a deficiency in a brain chemical called dopamine causes restless legs syndrome.
People with restless legs syndrome (RLS) often have a family history of the disorder. Researchers have detected at least six genetic locations or factors that might be responsible for this condition. Two of the genes are associated with spinal cord development. None of the genes have been associated with dopamine or iron-regulating systems, though these are considered strong causal factors.
What is the Definition of Sleep Apnea?
Apnea is defined as a cessation of oronasal airflow of at least 10 seconds in duration. When it occurs 30 or more times during a 7-hour period of nocturnal sleep, it is called obstructive sleep apnea (OSA) and requires immediate intervention to prevent it from becoming life-threatening.
Description of Sleep Apnea
In the most common form of the condition - obstructive apnea (also called upper airway apnea) - air stops flowing through the nose and mouth, but throat and abdominal breathing efforts are uninterrupted. The snoring that results is produced when the upper rear of the mouth (the soft palate and the cone-shaped tissue - the uvula - that descends from it) relaxes and vibrates as air passes in and out. This sets up an air current between the palate and the base of the tongue, resulting in snoring.
Typically, the individual will wake up, emit a vigorous snort or grunt while gasping for air, then immediately fall back to sleep, only to repeat the cycle.
In another form of the disorder, central apnea, both oral breathing and throat and abdominal breathing efforts are simultaneously interrupted. In a third type of apnea, mixed apnea, a brief period of central apnea is followed by a longer period of obstructive apnea.
Sleep apnea can be recognized by a number of symptoms. Loud and intermittent snoring is one warning signal. The person who has sleep apnea may experience a choking sensation, early-morning headaches, or extreme daytime sleepiness as well. His bed partner or roommate might comment on his excessive body movements or his snorting or gasping for breath during sleeping.
If the condition is suspected, it should be reported to a physician, who may recommend evaluation by a specialist in sleep disorders. Since sleeping pills may be harmful for people with sleep apnea, they should not be taken if the condition is suspected.
Causes of Sleep Apnea
Sleep apnea is believed to affect at least 1 out of every 200 Americans - 70 to 90 percent are men, mostly middle-aged and usually overweight. But the condition can afflict both men or women at any age.
Symptoms of Sleep Apnea
People with this disorder actually may stop breathing while asleep - even hundreds of times - without being aware of the problem. During an apnea attack, the snorer may seem to gasp for breath, and the blood may become abnormally low.
In severe cases, a sleep apnea victim may actually spend more time not breathing than breathing and may be at risk for death.
Neurologic Abnormalities
Dopamine and Neurologic Abnormalities in the Brain. A variety of studies support the theory that an imbalance in neurotransmitters (chemical messengers in the brain), notably dopamine and serotonin, may play a part in RLS. Dopamine and serotonin cause numerous nerve impulses that affect muscle movement. The effect is similar to what happens in Parkinson's disease. Moreover, drugs that increase dopamine levels treat both disorders. However, Parkinson's disease itself does not seem to increase the risk for RLS. Nor does RLS early in life predispose a person to Parkinson's later on.
Neurologic Abnormalities in the Spine. Other research suggests that restless legs syndrome may be due to nerve impairment in the spinal cord. Researchers considered that such abnormalities were likely to start in nerve pathways in the lower spine. However, some patients with RLS have symptoms in the arms, indicating that the upper spine may also be involved.
Neuropathy. Some experts suggest that RLS, particularly if it occurs in older adults, may be a form of neuropathy, which is an abnormality in the nervous system outside the spine and brain. So far, there is no evidence of a causal relationship.
Abnormalities of Iron Metabolism
Iron deficiency, even at a level too mild to cause anemia, has been linked to restless legs syndrome (RLS) in some people. Studies suggest, in fact, that RLS in some people may be due to a problem with getting iron into cells that regulate dopamine in the brain. Some studies have reported RLS in 25 - 30% of people with low iron levels.
Deficiencies in Cortisol
Some research suggests that low cortisol levels in the evening and early night hours may be related to restless leg symptoms. Some patients experienced improvement in symptoms with low-dose hydrocortisone injections.
Causes of Periodic Limb Movement Disorder
The cause or causes of periodic limb movement disorder (PLMD) are not clear. Some research suggests that it may be due to abnormalities in the autonomic nervous system, which regulates the involuntary actions of the smooth muscles, heart, and glands.
RLS may often have a genetic basis, particularly in those who develop it before age 40. When the condition occurs in older adults, it is most likely due to a neurological problem.
RLS and PLMD can be causes of insomnia, with or without daytime sleepiness.
RLS occurs as a primary, early onset, familial form and as a secondary, later onset form. Secondary causes of RLS include anemia (particularly iron deficiency), uremia, peripheral neuropathy, and pregnancy. RLS has also been described in diabetes, hypo/hyperthyroidism, porphyria, COPD, peripheral vascular disease, ADHD, fibromyalgia, rheumatoid arthritis, sjogrens syndrome, carcinoma, obesity, decreased exercise, LS radiculopathy, spinal cord disease, ALS, polio, multiple sclerosis, deficiency states including Mg, folate, B12, Fe and drugs/toxins including lithium, TCA's, SSRI's, caffeine, smoking, benzo withdrawal, spinal anesthesia.
RLS is generally a lifelong condition for which there is no cure. Nevertheless, current therapies can control the disorder, minimizing symptoms and increasing periods of restful sleep. Symptoms may gradually worsen with age, although the decline may be somewhat faster for individuals who also suffer from an associated medical condition. In addition, some individuals have remissions—periods in which symptoms decrease or disappear for days, weeks, or months—although symptoms usually eventually reappear. A diagnosis of RLS does not indicate the onset of another neurological disease, such as Parkinson’s disease.
Peripheral neuropathy is a problem with the nerves that carry information to and from the brain and spinal cord to the rest of the body. This can produce pain, loss of sensation, and an inability to control muscles.
* "Peripheral" means nerves further out from the center of the body, distant from the brain and spinal cord (which are called the central nervous system).
* "Neuro" means nerves.
* "Pathy" means abnormal.
One set of peripheral nerves relays information from your central nervous system to muscles and other organs. A second set relays information from your skin, joints, and other organs back to your central nervous system.
Peripheral neuropathy means these nerves don't work properly. Peripheral neuropathy may involve damage to a single nerve or nerve group (mononeuropathy), or it may affect multiple nerves (polyneuropathy).
There are many reasons for nerves to malfunction. In many cases, no cause can be found.
Nerve damage can be caused by:
* Diseases that run in families (hereditary disorders), such as:
o Charcot-Marie-Tooth disease
o Friedreich's ataxia
* Diseases that affect the whole body (systemic or metabolic disorders) such as:
o Cancer
o Diabetes (diabetic neuropathy)
o Dietary deficiencies (especially vitamin B12)
o Excessive alcohol use (alcoholic neuropathy)
o Hypothyroidism
o Multiple myeloma
o Uremia (from kidney failure)
* Infections or inflammation, including:
o Colorado tick fever
o Guillain-Barre syndrome
o Hepatitis
o HIV
o Lyme disease
o Polyarteritis nodosa
o Rheumatoid arthritis
o Sarcoidosis
o Sjogren syndrome
o Syphilis
o Systemic lupus erythematosus
* Exposure to poisonous substances such as:
o Glue sniffing or inhaling other toxic compounds
o Heavy metals (lead, arsenic, and mercury are most common)
o Industrial chemicals -- especially solvents
o Nitrous oxide
* Neuropathy secondary to medications, most commonly:
o Cisplatin
o Isoniazid
o Paclitaxel (Taxol)
o Pyridoxine (vitamin B6)
o Vincristine
* Miscellaneous causes:
o Compression of a nerve by nearby body structures or by casts, splints, braces, crutches, or other devices
o Decreased oxygen and blood flow (ischemia)
o Prolonged exposure to cold temperatures
o Prolonged pressure on a nerve (such as a long surgery)
o Trauma to a nerve
Peripheral neuropathy is very common. Because there are many types and causes of neuropathy and doctors don't always agree on the definition, the exact incidence is not known.
The outcome depends on the cause of peripheral neuropathy. In cases where a medical condition can be found and treated, the outlook may be excellent. However, in severe neuropathy, nerve damage can be permanent, even if the cause is treated.
For most hereditary neuropathies, there is no cure. Some of these conditions are harmless. Others get worse quickly and may lead to permanent, severe complications.
Serotonin and Sleep Disordered Breathing in Parkinson's Disease
Clinical Intervention Awards 2007
Objective/Rationale:
Sleep related problems are a major cause of impairment in Parkinson's disease. Recent studies indicate a high incidence of a disabling sleep disorder – sleep disordered breathing (SDB; known also as obstructive sleep apnea) in Parkinson's disease. Brain systems using the neurotransmitter serotonin are involved in control of breathing during sleep. Degeneration of serotonin systems occurs in Parkinson's disease. We will determine if loss of serotonin brain systems underlies sleep disordered breathing in Parkinson disease.
a. Benzodiazepines. They tend to depress one's central nervous system in order for sufferers to be able to sleep better despite the symptoms. However, those who have sleep apnea should not use them.
Here is the chain: Stress -> RLS -> peripheral neuropathy -> obstructive apnea -> PLMD: side-effects: memory loss, stroke, hipoxic, lack of concentration. Possible underlying disease: Parkinson's. It's all related
Happy ending, ain't it?
La venganza es un plato que se sirve helado
Hace 13 años.
