Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Sleep apnea is a disorder characterized by a reduction or pause of breathing (airflow)
during sleep.
It is common among adults but rare among children. Although a diagnosis of sleep
apnea often will be suspected on the basis of a person's medical history, there
are several tests that can be used to confirm the diagnosis. The treatment of
sleep apnea can be either surgical or nonsurgical.
An apnea is a period of time during which breathing stops or is markedly
reduced. In simplified terms, an apnea occurs when a person stops breathing for
10 seconds or more. If a person stops breathing completely or take less than 25% of a normal breath for a period that lasts 10 seconds or more,
this is an apnea. This definition includes complete stoppage of airflow. Other definitions of apnea that may be used include at least a 4% drop in oxygen in the blood, a direct result of the reduction in the transfer of oxygen into the blood when breathing stops.
Apneas usually occur during sleep. When an apnea occurs, sleep usually is disrupted due to inadequate breathing and poor oxygen levels in the blood. Sometimes this means the person wakes up completely, but sometimes this can mean the person comes out of a deep level of sleep and into a more shallow level of sleep. Apneas are usually measured during sleep (preferably in all stages of sleep) over a
2-hour period. An estimate of the severity of apnea is calculated by dividing the number of apneas by the number of hours of sleep, giving an apnea index (AI in apneas per hour); the greater the AI, the more severe the apnea.
A hypopnea is a decrease in breathing that is not as severe as an apnea. Hypopneas usually occur during sleep and can be defined as 69% to 26% of a normal breath. Like apneas, hypopneas also may be defined as a 4% or greater drop in oxygen in the blood. Like apneas, hypopneas usually disrupt the level of sleep. A hypopnea index (HI) can be calculated by dividing the number of hypopneas by the number of hours of sleep.
The apnea-hypopnea index (AHI) is an index of severity that combines apneas and hypopneas. Combining them gives an overall severity of sleep apnea including sleep disruptions and desaturations (a low level of oxygen in the blood). The apnea-hypopnea index, like the apnea index and hypopnea index, is calculated by dividing the number of apneas and hypopneas by the number of hours of sleep.
Another index that is used to measure sleep apnea is the respiratory disturbance index (RDI). The respiratory disturbance index is similar to the apnea-hypopnea index; however, it also includes respiratory events that do not technically meet the definitions of apneas or hypopneas, but do disrupt sleep.
Sleep apnea is formally defined as an apnea-hypopnea index of at least 15 episodes/hour in a patient if
he or she does not have medical problems that are believed to be caused by the sleep apnea. This is the equivalent of approximately one episode of apnea or hypopnea every 4 minutes.
High blood pressure, stroke, daytime sleepiness, congestive heart failure (low flow of blood to the heart), insomnia,
and mood disorders can be caused or worsened by sleep apnea. In the presence of these conditions, sleep apnea is defined as an apnea-hypopnea index of at least five episodes/hour. This definition is stricter because these individuals may be already experiencing the negative medical effects of sleep apnea, and it may be important to begin treatment at a lower apnea-hypopnea index.
Sleep apnea may lead to frequent awakening of the bed partner
resulting in insomnia and its associated symptoms.
Obstructive sleep apnea can also be associated with long-term
complications if not diagnosed and treated properly. Some of these complications
may include:
high blood pressure (hypertension),
ischemic heart disease (poor blood flow to the heart),
heart attack,
heart failure,
irregular heart rate,
pulmonary hypertension (elevation of blood pressure in blood vessels of
the lungs), or
Congestive heart failure (CHF) is a condition in which the heart's function as a pump is inadequate to meet the body's needs. A poor blood supply resulting
Sinus infection (sinusitis) signs and symptoms include headache, fever, and facial tenderness, pressure, or pain. Treatments of sinus infections are generally
Anxiety is a feeling of apprehension and fear characterized by physical symptoms. Anxiety disorders are serious medical illnesses that affect approximately
Temporomandibular joint disorder, or TMJ, is a disorder of the temporomandibular joint(s) that causes signs and symptoms including ear pain, bite problems,
Polycythemia (elevated red blood cell count) causes are either primary (aquired or genetic mutations) or secondary (diseases, conditions, high altitude).
Insulin resistance is the diminished ability of cells to respond to the action of insulin in transporting glucose (sugar) from the bloodstream into muscle
Heart attack happens when a blood clot completely obstructs a coronary
artery supplying blood to the heart muscle. A heart attack can cause chest pain,
Restless leg syndrome (RLS or restless legs syndrome) is a common cause for painful legs that typically eases with motion, and becomes worse and more noticeable
Atrial fibrillation is an abnormality in the heart rhythm which involves irregular and often rapid beating of the heart. Symptoms may include palpitations,
Nonalcoholic fatty liver disease (NAFLD) refers to a wide spectrum of liver disease ranging from simple fatty liver (steatosis), to nonalcoholic steatohepatitis
Marfan syndrome is hereditary condition affecting connective tissue. A person with Marfan syndrome may exhibit the following symptoms and characteristics:
Pulmonary hypertension is an abnormal elevation of the pressure in the pulmonary circulation caused by the constriction of the blood vessels that supply
Chronic fatigue syndrome is a debilitating and complex disorder characterized by profound fatigue that lasts 6 months or longer, is not improved by bed
Fatigue can be described in various ways. Sometimes fatigue is described as feeling a lack of energy and motivation (both mental and physical). The causes
High blood pressure (hypertension) means high pressure (tension) in the arteries. Treatment for high blood pressure include lifestyle modifications (alcohol,
Male sexual dysfunction can be caused by physical or psychological problems. Common sexual problems in men include erectile dysfunction (impotence or ED),
It is thought that the tonsils and adenoids assist the body in fighting incoming bacteria and viruses by helping the body form antibodies. This is thought
Heart disease (coronary artery disease) is caused by a buildup of cholesterol deposits in the coronary arteries. Risk factors for heart disease include
Snoring, like all other sounds, is caused by vibrations that cause particles in the air to form sound waves. While we are asleep, turbulent air flow can
Insomnia is the perception or complaint of inadequate or poor-quality sleep because of difficulty falling asleep; waking up frequently during the night
A number of vital tasks carried out during sleep help maintain good health and enable people to function at their best. Sleep needs vary from individual
Women's health is an important topic area to guide a woman through the stages of her life, as well as knowing the conditions and diseases that may occur.
Wisdom teeth, otherwise known as third molars, are the last set of teeth to
develop. Sometimes these teeth emerge from the gum line and the jaw is large
enough to allow room for them, but most of the time, this is n"...