Racial differences in HLA antigen frequency and hypertensive renal failure

Black patients with hypertension are six times more likely to develop end-stage renal disease than are their white counterparts. To determine if genetic differences associated with the Human Leukocyte Antigen (HLA) system account for racial variation in hypertensive renal failure, we examined antigenic frequencies from a large renal transplant registry. Human Leukocyte Antigen phenotypes from cadaveric renal transplant recipients and donors in the South Eastern Organ Procurement Foundation database from 1982 to 1986 were analyzed. One thousand six hundred four renal transplant recipients with hypertensive renal failure as the cause of end stage renal disease (cases) were compared with 4506 race-matched cadaveric kidney donors (controls). Log-linear models were used to assess the relationship between hypertensive renal failure and prevalence of each HLA phenotype. Bonferroni adjustments of P values were used to correct for multiple comparisons. Comparison of HLA frequencies between blacks and whites with hypertensive renal failure demonstrated that blacks had an increased frequency of HLA-DR3 beyond that normally known to exist between black and white populations. Black cases compared to black controls had an 8.6% increase in HLA-DR3 frequency contrasted with a 1.6% decrease in the frequency of this antigen between white cases and white controls. This absolute 10.2% difference between the races was significant (P = .02) because the control black and white populations had nearly identical frequencies for this antigen. White cases compared to white controls had lower HLA-A1 and B8 frequencies (21.2% v 30.6%, P = .0005 and 13.7% v 22.3%, P = .001, respectively) and a greater HLA-B35 frequency (20.7% v 14.2%, P = .02).(ABSTRACT TRUNCATED AT 250 WORDS)