Dyslipidemia has been reported to be common in subjects with obstructive sleep apnea (OSA), but this may be comorbid with obesity or visceral obesity which are highly prevalent in those with OSA. This prospective cohort study investigated the relationship of OSA to lipid profile in Chinese subjects.
Consecutive Chinese subjects of male sex, with no history of cardiovascular disease, diabetes mellitus, hyperlipidemia or significant chronic illness or medications, were recruited from our sleep laboratory. Their demographic and anthropometric data, fasting lipid profile (cholesterol, triglycerides, low density lipoprotein-cholesterol (LDL-cholesterol) & high density lipoprotein-cholesterol (HDL-cholesterol), apolipoproteins A1 & B (Apo A1 & B), and polysomnographic findings were collected. The relationships between apnea-hypoapnea index (AHI) and each lipid parameter were examined with multiple linear regression, adjusted for obesity (body mass index or waist circumference).
98 subjects were recruited, aged between 21 and 65. OSA was defined as AHI≥5. 73 subjects had OSA. Significant linear relationships were present between AHI and waist circumference, body mass index (BMI), LDL-cholesterol, HDL-cholesterol, Apo B, LDL-cholesterol:HDL-cholesterol and Apo B:Apo A1 (all p<0.05). On multiple linear regression analysis, with lipid parameters as dependent variables, adjusted for BMI, AHI was associated with Apo B (p<0.05), total cholesterol:HDL-cholesterol (p< 0.01), LDL-cholesterol:HDL cholesterol (p< 0.05)and Apo B:Apo A1 (p<0.05).
In this cohort of Chinese subjects, AHI was associated with apolipoprotein B, apolipoprotein and cholesterol fraction ratios, controlled for obesity.
OSA may have an independent effect on adverse lipid profile, and thus confer independently to cardiovascular risks.
Jamie Lam, University grant monies This project was supported by the Hong Kong Research Grants Council, The University of Hong Kong, HKU7307/00M