Obesity and dyslipidemia in Chinese patients with obstructive sleep apnea

Abstract

Background Obesity is a characteristic feature of OSA in adults, in both Caucasians and Chinese (1,2). There is a high prevalence of obesity in patients with OSA. This prospective cohort study investigated the relationship of obesity and lipid profiles to OSA in Chinese patients in Hong Kong. Methods 50 Chinese subjects of male sex, aged 25 to 65, were recruited from our sleep laboratory. Demographic and anthropometric data, fasting lipid profile (cholesterol, triglyceride, LDL & HDL-cholesterol, fatty acid, Apolipoproteins A & B) and polysomnographic findings were collected. MRI scan of abdomen was also performed to estimate the amount of abdominal fat. Results The major dependent outcome variable was the apnea-hypopnea index (AHI). OSA was defined as AHI ≥ 5. Independent measures were body weight (BW), BMI, waist circumference, abdominal fat analysis (MRI imaging), and the lipid profile. Significant linear relationships of AHI with BW, BMI, abdominal fat, HDL-cholesterol and Apolipoprotein B were demonstrated (P < 0.05). Multiple linear regression analysis showed that obesity measured by either abdominal fat (P < 0.001) or waist circumference (P < 0.001) or BMI (P < 0.001) as well as Apolipoprotein B levels (P < 0.05) were independently associated with AHI. Conclusion In this cohort of Chinese patients, Apolipoprotein B was associated with AHI as controlled for obesity, and it may contribute to atherosclerosis in OSA. References 1 Ip M.S.M., Lam B., Lauder I.J., et al. A community study of sleep-disordered breathing in middle-aged Chinese men in Hong Kong. Chest 2001;119:62–69. 2 Ip M.S.M., Lam B., Tang L.C.H., et al. A community study of sleep-disordered breathing in middle-aged Chinese women in Hong Kong. Chest 2004;125(1):127–134. This project was supported by Lee Wing Tat Cardiorespiratory Research Grant, The University of Hong Kong.