Relations of plasma TG and HDL-C concentrations to body composition and plasma insulin levels are altered in men with small LDL particles.

Low-density lipoprotein (LDL) subclass pattern B is characterized by a predominance of small, dense LDL particles (LDL peak particle size < or = 255 A), increased plasma triglyceride (TG) levels, reduced high-density lipoprotein (HDL) cholesterol levels, and glucose intolerance. This study tested the hypothesis that there are differences in the regulation of TG and HDL metabolism by insulin in patients with LDL pattern B. The study group comprised 160 healthy older (60 +/- 8 years, mean +/- SD) men. Forty-nine of the men (31%) had LDL pattern B. These men had a higher waist-to-hip ratio (WHR) (0.98 +/- 0.06 versus 0.95 +/- 0.06, P < .005) and lower maximal aerobic capacity (VO2max) (P < .005) than the 111 men of comparable age with a predominance of larger LDL particles (LDL peak particle size > 255 A, LDL pattern A). Men with LDL pattern B also had higher TG (1.76 +/- 0.60 versus 1.03 +/- 0.41 mmol/L, P < .0001) and lower HDL cholesterol (0.83 +/- 0.13 versus 1.06 +/- 0.29 mmol/L, P < .0001) and percent HDL2 subspecies (by gradient gel electrophoresis) (31 +/- 4 versus 43 +/- 6, P < .0001) levels than men with LDL pattern A, but the total cholesterol and LDL cholesterol levels did not differ between groups. Fasting glucose and insulin levels also did not differ between groups, but plasma glucose and insulin levels measured at 90 and 120 minutes during an oral glucose tolerance test were significantly higher in men with LDL pattern B.(ABSTRACT TRUNCATED AT 250 WORDS)