Racial Differences in Plasma High-Density Lipoproteins in Patients Receiving Hemodialysis: A Possible Mechanism for Accelerated Atherosclerosis in White Men

Among 346 nondiabetic patients receiving long-term hemodialysis, cardiovascular mortality was higher in white than in black men (P<0.02) but was similar between black and white women, despite the higher incidence of nephrosclerosis in black men and women (59 and 58 per cent vs. 8 and 10 per cent, respectively; P<0.0001). There were significant racial differences in plasma lipid and apoprotein levels in a subset of 100 of these patients. The white men had higher levels of plasma triglyceride and lower levels of high-density-lipoprotein (HDL) cholesterol, apoprotein A-I, and apoprotein A-II than black men; concentrations of HDL, apoprotein A-I, and apoprotein A-II were also lower in white than in black women. The distribution of the HDL subfractions HDL₂, HDL₃, and HDL_3D, as determined by zonal ultracentrifugation, was normal in black and abnormal in white men receiving hemodialysis. HDL₂ concentrations were higher in black than in white men by both zonal analysis (P<0.05) and polyanionic precipitation of the HDL subfractions (P<0.01). The distributions and concentrations of HDL₂ and HDL_3L were similar in black and white women. Thus, there are marked racial differences in HDL in male patients receiving hemodialysis. The abnormalities in HDL and the hypertriglyceridemia in the white men may explain their high rate of cardiovascular mortality. (N Engl J Med 1983; 308:1245–52.) Several hemodialysis centers have reported an increased mortality from cardiovascular diseases and have attributed it to atherosclerotic complications.^{1 2 3 4 5} Data from other centers suggest that mortality from cardiovascular causes among patients receiving hemodialysis may be overestimated because of the inclusion of patients with prior coronary heart disease, and that atherosclerosis is not accelerated in patients receiving hemodialysis.^6,7 Whatever the reasons for these divergent data, a high mortality from cardiovascular disease is reported from hemodialysis centers serving predominantly white populations.^{1 2 3 4 5} Among these populations there is an increased prevalence of hypertriglyceridemia and lower plasma levels of highdensity-lipoprotein (HDL) cholesterol, as compared with normal.