Visceral adipose tissue and low-density lipoprotein particle size in middle-aged versus young men

Age is associated with increased deposition of visceral adipose tissue. We examined whether this age related change in regional adipose tissue distrib ution had an impact on low-density lipoprotein (LDL) particle size. For thi s purpose, the plasma lipoprotein-lipid profile, including LDL peak particl e diameter as determined by gradient gel electrophoresis, was assessed in 3 8 young men (aged 26.4 +/- 4.2 years, mean +/- SD) and compared with 40 mid dle-aged men (55.9 +/- 6.2 years). Middle-aged men had higher values for to tal body fat and visceral adipose tissue area as measured by computed tomog raphy than young men (P < .001). Although significant differences were note d between the two age groups for plasma cholesterol, triglyceride (TG), apo lipoprotein B (apo B), LDL cholesterol, and LDL apo B, as well as the chole sterol to high-density lipoprotein (HDL) cholesterol ratio (P < .001), no d ifference was found for LDL peak particle size between young and middle-age d men. While visceral adipose tissue was a significant correlate of plasma lipoprotein levels, the fasting TG concentration was the best predictor of LDL particle size, and the regression of TG levels on LDL peak particle dia meter was not different between the two age groups. These results suggest t hat middle-aged men are characterized by an increased concentration of LDL particles (reflected by increased LDL apo B levels) but not by a reduced LD L peak particle size compared with young men. It is therefore proposed that in the absence of an important age-related change in TG levels, age per se is associated with an increased concentration of atherogenic LDL particles rather than a reduction of LDL particle diameter. Copyrights (C) 1999 by W .B. Saunders Company.