Adiposity and cardiovascular risk factors in men with obstructive sleep apnea

To assess anthropometric characteristics of patients with obstructive sleep apnea (OSA) and their relationship to cardiovascular risk factors (dyslipidemia, hypertension, glucose intolerance) and severity of breathing abnormalities during sleep.

Case series.

Referral-based sleep disorder center serving Rhode Island and Southeastern Massachusetts.

Forty-five men, 26 to 65 years old, with OSA diagnosed by clinical and polysomnographic criteria.

By national health survey criteria, 51 percent of patients were in the upper fifth percentile for weight, whereas 91 to 98 percent were in the upper fifth percentile for skinfold thicknesses (triceps, subscapular, triceps plus subscapular). Severe upper body obesity, as defined by a waist-hip ratio (WHR) greater than or equal to 1.00, was present in 51 percent of the patients. The WHR, however, did not correlate significantly with the severity of respiratory disturbances during sleep. The patients had higher prevalences of hypertension and impaired glucose tolerance than expected, but normal prevalences of hypercholesterolemia, low high-density lipoprotein cholesterol, and overt diabetes mellitus. Skinfold thicknesses correlated more closely with the severity of OSA than did body mass index (BMI) or neck circumference.

Men with OSA have a marked excess of body fat that is not always reflected in measurements of body weight or BMI. Also, upper body obesity, hypertension, and impaired glucose tolerance occur more frequently than expected in this population. Severe adiposity may not only promote development of the respiratory abnormalities of OSA, but also may contribute directly to the increased cardiovascular risk associated with OSA.