There is disagreement about the prevalence and character of lipoprotein lipid abnormalities in renal transplant patients. To test the hypothesis that these abnormalities may be related to the coexistence of medical conditions and medications which affect lipoprotein metabolism in these patients, triglyceride (TG), cholesterol (C), high-density lipoprotein (HDL) and HDL-C subfractions were measured in 26 transplanted patients (10 F/16 M), control subjects matched for age, sex, weight and race and uremic patients being treated with hemodialysis. Female transplant recipients had higher TG (181 +/- 47 vs. 68 +/- 6 mg/dl; p less than 0.001), C (242 +/- 19 vs. 165 +/- 9 mg/dl; p less than 0.01), and low-density lipoprotein (LDL)-C (155 +/- 15 vs. 93 +/- 8 mg/dl; p less than 0.01) than controls. Levels of HDL-C were similar, but HDL2 was significantly lower in the transplanted patients (9 +/- 2 vs. 19 +/- 2 mg/dl; p less than 0.01). Compared to the uremic patients, female transplanted patients had higher C (242 +/- 19 vs. 178 +/- 22 mg/dl; p less than 0.01), LDL-C (155 +/- 15 vs. 94 +/- 18 mg/dl; p less than 0.01), HDL-C (51 +/- 5 vs. 32 +/- 4 mg/dl; p less than 0.001) and HDL3-C (42 +/- 4 vs. 26 +/- 2 mg/dl; p less than 0.001); however, HDL2-C levels were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)