Hyperhomocysteinemia in end-stage renal failure.

The end-stage renal disease (ESRD) population experiences an excess morbidity and mortality due to arteriosclerotic cardiovascular disease (CVD) outcomes. Specifically, event rates for myocardial infarction and stroke are 5- to 10-fold in ESRD patients on maintenance dialysis than in the general population. Recently, there is controlled evidence that hyperhomocysteinemia occurs more commonly than any of the traditional CVD risk factors in ESRD patients. Prolonged exposure of endothelial cells to homocysteine impairs the production of nitric oxide and endothelium-dependent vasodilatation, they combine with low-density lipoprotein cholesterol to produce aggregates that are taken up by vascular macrophages in the arterial intima (foam cells), produce aggregatory effects on the platelets, and decrease endothelial antithrombotic activity due to changes in the thrombomodulin function. Current treatment regimens for ESRD hyperhomocysteinemia, which are based on the pharmacological doses of folic acid (5 to 15 mg/day), frequently result in suboptimal lowering of Hcy concentrations. Other potential therapeutic approaches (such as oral N-acetylcysteine at 1.2 g/day) merit controlled investigation.