Sleep apnea risk factors


 * Associate Editor(s)-In-Chief: Kashish Goel, M.D.

Populations at risk
Individuals with decreased muscle tone, increased soft tissue around the airway, and structural features that give rise to a narrowed airway are at high risk for obstructive sleep apnea. Men, whose anatomy is typified by increased body mass in the torso and neck, are more typical sleep apnea sufferers, especially through middle age and older. Adult women suffer typically less frequently and to a lesser degree than men do, owing partially to physiology, but possibly to emerging links to levels of progesterone. Prevalence in post-menopausal women approaches that of men in the same age range.

Adults
In adults, the most typical individual with obstructive sleep apnea syndrome is obese, with particular heaviness at the face and neck. The hallmark symptom of obstructive sleep apnea syndrome in adults is excessive daytime sleepiness. Typically, an adult or adolescent with severe long-standing obstructive sleep apnea will fall asleep for very brief periods in the course of usual daytime activities if given any opportunity to sit or rest. This behavior may be quite dramatic, sometimes occurring during conversations with others at social gatherings.

Children
Obstructive sleep apnea syndrome was described more than a century ago, but obstructive sleep apnea in children was first described in the 1970s. It is a common but underdiagnosed condition in children that may ultimately lead to substantial morbidity if left untreated. Although this so called "hyper-somnolence" (excessive sleepiness) may also occur in children, it is not at all typical of younger children with sleep apnea. Toddlers and young children with severe obstructive sleep apnea instead ordinarily behave as if "over-tired" or "hyper". Studies have suggested that as many as 25 percent of children diagnosed with attention-deficit hyperactivity disorder may actually have symptoms of obstructive sleep apnea and that much of their learning difficulty and behavior problems can be the consequence of chronic fragmented sleep. Bed-wetting, sleep-walking, retarded growth, other hormonal and metabolic problems, even "failure to thrive" can be related to sleep apnea.Adults and children with very severe obstructive sleep apnea also differ in typical body habitus. Adults are generally heavy, with particularly short and heavy necks. Young children, on the other hand, are generally not only thin but may have "failure to thrive", where growth is reduced. Poor growth occurs for two reasons: the work of breathing is high enough so that calories are burned at high rates even at rest, and the nose and throat are so obstructed that eating is both tasteless and physically uncomfortable. Obstructive sleep apnea in children, unlike adults, is almost always caused by obstructive tonsils and adenoids and is usually cured with tonsillectomy and adenoidectomy.

Parents occasionally comment on breathing difficulties during sleep (eg, gasps or heroic snorts), unusual sleeping positions, morning headaches, daytime fatigue, irritability, poor growth and weight gain, and behavioral problems. Nevertheless, even in cases in which a sleep specialist conducts the diagnostic interview, the accuracy of obstructive sleep apnea prediction is poor and does not exceed a sensitivity and specificity of 50-60%, particularly in distinguishing obstructive sleep apnea from benign snoring. .