Associations of leptin with body fat distribution and metabolic parametersin non-insulin-dependent diabetic patients: No effect of apolipoprotein E polymorphism

Leptin levels have been shown previously to be associated with anthropometr ic parameters such as the body mass index (BMI), total body fat, and subcut aneous fat. Since apolipoprotein E (apoE) polymorphism is known to be a gen etic marker affecting the relationship between certain anthropometric and m etabolic parameters, we evaluated whether the leptin level and/or associati ons between the leptin level and body composition in non-insulin-dependent diabetic patients could be determined by apoE polymorphism. In 171 type 2 d iabetic patients (105 male and 66 female), body composition (BMI, waist to hip ratio [WHR], fat mass, and visceral fat) was measured and fasting blood samples were obtained to determine the apoE genotype, leptin, glucose, and insulin levels, and the lipid profile. The mean leptin level for the whole group was 11.7 +/- 9.3 ng/mL, with a significant difference (P < .001) bet ween men (7.1 +/- 4.9 ng/mL) and women (19.0 +/- 10.1 ng/mL). No difference was found for leptin levels or anthropometric variables between the 3 diff erent apoE genotypes (E3/E3 homozygotes, E2 carriers, and E4 carriers). Onl y low-density lipoprotein (LDL) cholesterol was significantly different bet ween the 3 apoE subgroups. The correlations of leptin with anthropometric v ariables, especially visceral fat, tended to be different between the 3 apo E groups, but this was not independent and no effect was found after contro lling for the other parameters in the model. A multiple regression model co ntaining gender, subcutaneous fat, fasting glucose, triglycerides, and high -density lipoprotein (HDL) cholesterol explained 81% of the variance in lep tin levels. We conclude that apoE polymorphism has no effect on the leptin level or its associations with other anthropometric and metabolic parameter s. Copyright (C) 2000 by W.B. Saunders Company.