Sleep apnea refers to a sleeping disorder wherein breathing is briefly and repeatedly interrupted during sleep. Obstructive sleep apnea occurs when the muscles in the back of the throat fail to keep the airway open. In some cases of sleep apnea, the brain fails to properly control breathing during sleep. This disease has many different possible factors. Some of the most common causes of sleep apnea are discussed herein.

Obesity

A major risk factor for the development and progression of sleep apnea is obesity. Obese patients are twice at risk than adults who are at a healthy weight. This is because fat deposits in tissues of the upper airway, resulting in a smaller lumen and increased collapsibility. In the thorax, this issue reduces chest compliance and functional residual capacity.

Genetic Syndromes

A tumor or growth in the airway or birth defects like Down and Pierre-Robin syndromes can cause sleep apnea. Enlargement of the tongue, adenoids, tonsils, and a decreased muscle tone in the upper airway occurs due to Down Syndrome. In Pierre-Robin syndrome, the patient develops a small lower jaw and the tongue tends to ball up and fall to the back of the throat. Other genetic conditions that may lead to sleep apnea are cleft lip and cleft lip palate, and congenital central hypoventilation syndrome.

Endocrine and Neuromuscular Conditions

The endocrine system produces a hormone that can cause sleep disturbances. Disorders of endocrine associated with sleep apnea are hypothyroidism, acromegaly, and polycystic ovary syndrome.

Neuromuscular conditions can interfere with brain signals to airway and chest muscles, leading to sleep apnea. They include stroke, amyotrophic lateral sclerosis, Chiari malformations, myotonic dystrophy, post-polio syndrome, dermatomyositis, myasthenia gravis, and Lambert–Eaton myasthenic syndrome.

Natural Causes

The inherited tendency towards anatomical abnormalities may reflect the fact that 25% to 40% of people with obstructive sleep apnea have family members with the condition. In African-Americans, Hispanics, and Pacific Islanders, studies have shown that sleep apnea is more common than Caucasians. Men with a neck circumference above 17 inches and women with a neck circumference above 15 inches also have a significantly increased risk of developing obstructive sleep apnea.

Stress and Smoking

The release of stress hormones triggered by frequent decreases in blood oxygen levels and reduced sleep quality may be related to sleep apnea. Even excessive smoking, alcohol use, and frequent use of other sedatives may also cause obstructive sleep apnea.

Aging

The prevalence of obstructive sleep apnea is between 4% and 9% for middle-aged adults, though the condition often remains undiagnosed and untreated. The brain’s ability is affected by aging as the upper airway throat muscles stiff during sleep. People who have advanced heart or kidney failure may also have sleep apnea, caused by fluid build-up in their neck, which can obstruct the upper airway.