Abstract 873: Going Beyond Obstructive Sleep Apnea Syndrome: The Relationship Between Daytime Sleepiness and Metabolic Syndrome in Mexican-American Women
Background: Impaired sleep has been associated with decreased insulin sensitivity and increased blood pressure and sympathetic nervous system activity, which may contribute to the development of the metabolic syndrome (MetS). To date, most research regarding impaired sleep and MetS has focused on Obstructive Sleep Apnea Syndrome (OSAS) as a primary driver of the relationship. Little to no work has examined this association within Latinos, who have one of the highest rates of MetS in the U.S. In this study, we examined the relationship between daytime sleepiness, an indicator of impaired sleep, and MetS in a group of Mexican-American women.
Methods: A community sample of 251 middle aged (M=49.83 years) Mexican-American women underwent assessment of MetS components (blood pressure, waist circumference, fasting glucose, HDL, and triglycerides) and completed the Epworth Sleepiness Scale, a measure of daytime sleepiness (coded into quintiles), and the Pittsburgh Sleep Quality Index, a measure of sleep disturbances. MetS was defined according to Adult Treatment Panel III/NHLBI criteria.
Results: After adjustment for age, education, current smoking, menopausal status, nativity (U.S. born versus not), and use of sleep medication, women who reported greater daytime sleepiness were at significantly increased odds of having MetS [OR(95% CI) = 1.30 (1.03,1.63), p= .02]. The relationship was linear and persisted after controlling for chronic stress, dietary factors and BMI [OR(CI 95%) 1.36 (1.01,1.84), p= .04]. Further analyses revealed that controlling for sleep duration, sleep disturbances, and OSAS indicators (breathing difficulty, coughing/snoring) did not alter this relationship [OR(95% CI)1.31 (1.02,1.69), p= .03].
Conclusions: Daytime sleepiness is related to increased odds of MetS in Mexican-American women. Much of the research on the cardiovascular effects of sleep has focused on OSAS, but the persistence of the sleepiness effect even after controlling for OSAS indicators, suggests that the relationship extends beyond the possible association with OSAS. Sleepiness may be an independent indicator of heightened inflammatory processes which may in turn contribute to MetS and cardiovascular disease risks.