High-density lipoprotein cholesterol subfractions in chronic uremia.

Cholesterol content in high-density lipoprotein (HDL) subfractions has been studied in 108 patients at different evolutive stages of chronic renal failure (CRF) under conservative treatment. Results have been compared with healthy control subjects, patients receiving hemodialysis, and renal graft recipients. Significant low levels of total HDL and HDL2 cholesterol are observed in men with CRF. The more severe the CRF, the more likely that total HDL and HDL2 cholesterol will be low. Moreover, a significant inverse correlation is found between HDL2 cholesterol and serum creatinine levels. In women, although a decrease in total and HDL2 subfraction is observed, no significant differences are found across the severity of CRF. Serum HDL2 cholesterol levels are decreased in men and women receiving hemodialysis, while raised total HDL and HDL2 cholesterol levels are observed in normally functioning renal grafts. These results indicate that according to the "HDL hypothesis," despite other associated risk factors, the high cardiovascular mortality rates noted mainly in men with CRF under conservative treatment and in patients receiving hemodialysis could be explained, at least in part, by the sustained and progressive decrease in total HDL and HDL2 values. From this point of view, our study suggests the need to promote early kidney transplantation.