RACIAL-DIFFERENCES IN RENAL-ALLOGRAFT SURVIVAL - THE ROLE OF SYSTEMICHYPERTENSION

The rate of decline in the number of functioning renal allografts beyo nd the first year after transplantation has changed little in the last 25 years, and during long-term follow-up most allografts are lost due to chronic transplant rejection or patient death. The recipient race correlates with allograft survival, and African American recipients ha ve a lower allograft survival than Caucasians. The goal of the present study was to identify clinical variables present during the first six months after transplantation that predict the loss of renal allograft s beyond six months after transplantation, and in particular to determ ine the role of systemic hypertension on renal allograft survival in b lack and white recipients. This study includes 547 recipients of first cadaveric renal allografts performed at The Ohio Slate University. Al l patients were treated with a uniform immunosuppressive protocol and had a follow-up of at least three years. By multivariate analysis the following variables correlate with poor allograft survival: an elevate d serum creatinine concentration measured six months after transplanta tion (SCr6mo) (P < 0.0001); black race (P < 0.0001); increasing number s of acute rejection episodes (ATR) (P = 0.002); and young recipients (P = 0.026). Allograft survival is significantly worse in black (mean allograft half-life of 7.7 +/- 1.3 years) than in white recipients (24 +/- 3 years) (P < 0.0001). Black recipients also have a significantly higher six month average mean arterial blood pressure (MAP) (105 +/- 8 mm Hg) than white recipients (102 +/- 7 mm Hg) (P = 0.002). However, the prevalence of hypertension is not significantly different in blac k (33%) than in white recipients (26%). Furthermore, increasing MAP le vels correlate with a shorter allograft half-life in black recipients (P = 0.0002), bur not in white recipients (P = 0.84). Allograft surviv al was eight times shorter in hypertensive black (3.1 +/- 0.7 years) t han in hypertensive white recipients (24.6 +/- 7 years). In contrast, allograft survival was not statistically different between normotensiv e black and white patients. In conclusion, the presence of poorly cont rolled systemic hypertension, early after renal transplantation, corre lates with poor allograft survival in black recipients. Thus, systemic hypertension may explain, in part, differences in renal allograft sur vival between black and white patients.