THE ASSOCIATIONS OF HIGH-DENSITY-LIPOPROTEIN SUBCLASSES WITH INSULIN-LEVELS AND GLUCOSE-LEVELS, PHYSICAL-ACTIVITY, RESTING HEART-RATE, AND REGIONAL ADIPOSITY IN MEN WITH CORONARY-ARTERY-DISEASE - THE STANFORD CORONARY RISK INTERVENTION PROJECT BASE-LINE SURVEY

We used nondenaturing polyacrylamide gradient gel electrophoresis to e xamine the associations of high-density lipoprotein (HDL) subclasses w ith adiposity, physical activity, resting heart rate (an indicator of sympathetic drive), and plasma insulin and glucose levels in 97 men wi th angiographically documented coronary artery disease. These men neit her smoked nor used medications known to affect lipoproteins. The abso rbency of protein stain was used as an index of mass concentrations at intervals of 0.01 nm within five HDL subclasses: HDL(3c) (7.2 to 7.8 nm), HDL(3b) (7.8 to 8.2 nm), HDL(3a) (8.2 to 8.8 nm), HDL(2a) (8.8 to 9.7 nm), and HDL(2b) (9.7 to 12 nm). HDL peak diameter was determined from the predominant peak of the HDL particle distribution when plott ed against particle diameter. Four men who were non-insulin-dependent diabetics as defined by a fasting glucose exceeding 140 mg/dL had sign ificantly higher plasma HDL(3b) levels and significantly smaller HDL p eak dia meters than nondiabetic men, and were therefore excluded from further analyses. In the remaining 93 nondiabetic men, plasma HDL(3b) levels correlated positively with indices of truncal obesity (waist to hip ratio and subscapular skinfold), whereas plasma HDL(2b) levels co rrelated negatively with indices of total adiposity (body mass index [ BMI]) and truncal obesity (subscapular and abdominal skinfold). Fastin g plasma insulin levels correlated negatively with HDL(3a), HDL(2a), a nd HDL(2b). Obesity significantly affected the relationships of restin g heart rate with insulin and HDL subclasses. In heavier men (BMI > 25 .8 kg/m(2)) but not in the less obese men (BMI < 25.8 kg/m(2)), restin g heart rate was negatively correlated with HDL(3a), HDL(2a), and HDL( 2b) levels and HDL peak diameter and positively correlated with fastin g plasma insulin concentrations. Although the reported physical activi ty in heavier men also correlated with HDL(3a), HDL(2a), and resting h eart rate, the associations of resting heart rate with HDL(3a), HDL(2a ), and HDL(2b) could not be attributed to activity level. These analys es suggest that the influences of plasma insulin, regional adiposity, physical activity, and resting heart rate on HDL involve specific HDL subclasses. In the presence of increased adiposity, sympathetic drive and physical inactivity may reduce levels of larger HDL and the peak d iameter of the major HDL subspecies. Copyright (C) 1995 by W.B. Saunde rs Company