Obesity is one of the most important causes of sleep apnea. Scientists discovered that people who are overweight (BMI of 25 to 29) and obese (BMI of 30 and above) have the higher risk for OSA.
Numerous studies have shown correlations between the prevalence of obstructive sleep apnea syndrome and obesity.
The studies have demonstrated that obesity increases the rate of progression of sleep apnea, and weight gain further accelerates disease progression.
Even mildly overweight people are at risk of having obstructive apnea. Read the study here.
However, losing 10% of weight will decrease the AHI with 26%. Read the study here.
Enlarged tonsils or adenoids are the most common cause of upper airway obstruction, and hence obstructive sleep apnea (OSA), in children. The tonsils represent clusters of lymphatic/immune tissue at the back of the throat, while the adenoids represent the equivalent structures at the back of the nose.
Earlier clinical studies have established an association between OSA and behavior and sleep problems, low energy levels, and overall decreased daytime functioning.
A deviated nasal septum may lead to the development of obstructive sleep apnea (OSA). It is a frequently diagnosed disorder of the nose. The septum is composed of bone and cartilage and separates the nose into right and left passages in the nasal cavity. A deviated nasal septum is most commonly caused by trauma, usually a direct blow to the face. After healing, the nasal septum leans, or deviates, right or left.
Menopause may lead to the development of obstructive sleep apnea (OSA). Menopause is defined as the absence of menstrual periods in women for 12 consecutive months. During menopause, women experience ever decreasing levels of the sex hormones estrogen and progesterone. Both of these hormones assist in the promotion and regulation of sleep. It’s no surprise that sleep suffers as the levels of these hormones decline. In the United States, the average age of the onset of menopause is 51-years.
A large neck circumference, or the distance around the neck, may lead to the development of obstructive sleep apnea (OSA). As an individual gains weight, one area of the body that increases in circumference is the neck. Additionally, fat tissue increases in other areas of the body such as the base of the tongue and tissues surrounding the upper airways. The increase in fat tissue crowds the throat and upper airways leading to intermittent obstruction.
Smoking may lead to the development of obstructive sleep apnea (OSA). Smoking irritates the tissues of the upper airways leading to inflammation. The inflammation reduces the space for air flow and can cause intermittent obstruction. In a clinical trial published in Sleeping and Breathing, researchers established smoking as an independent risk factor for the development of OSA. Current smokers are 2.5-times more likely to develop OSA.
Alcohol relaxes the upper airway muscles and can lead to partial or complete airway obstruction during sleep.
Alcohol is also a risk factor for upper airway resistance syndrome (UARS), another dangerous sleep breathing disorder.
Men who consume more alcohol than average have 25% greater risk for developing OSA.
Evidence is accumulating that genetic factor may be one of the primary causes of sleep apnea. The risk factors arise from changes of the upper airway structure:
Male gender - Recent studies demonstrate that OSA is 2 to 3 times higher in men than women. However, this gap between man and women decreases after the menopause.
Why men are at higher risk for OSA is not entirely clear but appear to be related to hormonal influence.
Gender differences in the prevalence of obstructive sleep apnea may also be related to body fat distribution.
Men exhibit a more central fat distribution, including the neck, thereby increasing the risk for narrowing and blockage of the upper airway.
Hypothyroidism, especially myxedema, is associated with an increased prevalence of obstructive (from the damage of muscle function) and central sleep apnea (through blunted ventilatory response).
Macroglossia associated with hypothyroidism contributes to the higher frequency of sleep disordered breathing.
Sleep apnea syndrome is more common and often severe in acromegalic patients (a chronic disease marked by enlargement of the bones of the extremities, face, and jaw) presumably related to a large tongue narrowing the upper airway.