Pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients

OBJECTIVE: Obstructive sleep apnea syndrome (OSAS) is associated with increased cardiovascular morbidity and mortality. We investigated the values of brachial-ankle pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients. MATERIALS AND METHODS: Brachial-ankle pulse wave velocity (baPWV) was measured in 104 OSAS patients and 104 healthy control subjects matched for age, sex, and body mass index (BMI). BaPWV values were compared in both groups and investigated with respect to the number of risk factors for atherosclerosis, including hypertension, hypercholesterolemia, impaired glucose tolerance, smoking, and obesity. Comparisons were also made between 48 OSAS group cases and 90 control group cases free from hypertension, which has a major impact on baPWV. RESULTS: As compared to the control group, the OSAS group had significantly higher baPWV (1,645+/-349 cm/s vs 1,436+/-278 cm/s, p<0.0001), and values obtained for baPWV were significantly higher in the OSAS group than in the control group even in groups free from hypertension (1,453+/-216 cm/s vs 1,374+/-213 cm/s, p<0.05). In both groups, baPWV rose as the number of risk factors for atherosclerosis increased, but baPWV was higher in the OSAS group than in the control group even in a comparison of individuals entirely free from risk factors (1,400+/-200 cm/s vs 1,198+/-79 cm/s, p<0.05). CONCLUSION: The condition of OSAS itself is considered a possible risk factor for atherosclerosis. We believe that the usefulness of baPWV as an index of atherosclerosis merits further study in the frequently observed cases of OSAS complicated by cardiovascular disease.