Purpose: We investigated the relationships between the amount and distribution of body fat and fasting serum lipids and lipoproteins to explore whether coronary artery disease (CAD) risk may be mediated through effects on the serum lipid profile.
Patients and methods: We determined serum total cholesterol and triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, and HDL subfractions 2 and 3 in 103 healthy men, aged 21 to 77 years (mean 48.7). The amount and distribution of fat were determined directly by dual energy X-ray absorptiometry. Adiposity was determined as the ratio between total body fat tissue and total body lean tissue, while fat distribution was taken as the ratio between the mass of fat tissue in the android (central) and gynoid (hip and thigh) regions.
Results: Univariate analysis showed both adiposity and fat distribution to be correlated with total serum cholesterol and triglyceride concentrations (adiposity r = .20, .21; both P < 0.05: fat distribution r = .25, .38; P < 0.05, P < 0.001, respectively). Fat distribution was also negatively correlated with HDL2 cholesterol (r = -.20, P < 0.05). In multiple linear regression analysis, neither age nor adiposity was significantly correlated with any serum lipid or lipoprotein concentration, while increasing android-to-gynoid ratio was independently associated with elevated total serum triglyceride (r = .40, P < 0.01) and decreased HDL2 (r = -.25, P < 0.05) concentrations.
Conclusions: The association of both age and overall adiposity with the fasting serum lipid profile are mediated via their correlations with body fat distribution. In men, the distribution, rather than the amount, of body fat is related to adverse changes in serum lipids and lipoproteins, and hence potentially to increased CAD risk.