Arterial hypertension and renal allograft survival

Context Several observational studies have investigated the significance of hypertension in renal allograft failure; however, these studies have been complicated by the lack of adjustment for baseline renal function, leaving the role of elevated blood pressure in allograft failure unclear. Objective To examine the relationship between blood pressure adjusted for r enal function and survival after cadaveric allograft transplantation. Design Nonconcurrent historical cohort study conducted from 1985 through 19 97. Setting University teaching hospital. Participants A total of 277 patients aged 18 years or older who underwent c adaveric renal transplantation without another simultaneous organ transplan tation and whose allograft was functioning for a minimum of 1 year. Follow- up continued through 1997 (mean follow-up, 5.7 years). Main Outcome Measure Time to allograft failure (defined as death, return to dialysis, or retransplantation) by systolic, diastolic, and mean arterial blood pressure measurements at 1 year after transplantation. Results Multivariate Cox proportional hazards modeling demonstrated that no nwhite ethnicity, history of acute rejection, and nondiabetic kidney diseas e were significant predictors of failure (P = .01 for all), In addition, th e calculated creatinine clearance at 1 year had an adjusted rate ratio (RR) for allograft failure per 10 mL/min (0.17 mL/s) of 0.74 (95% confidence in terval [CI], 0.62-0.88). The RR per 10-mm Hg in crease in blood pressure me asured at 1 year after transplantation, after adjustment for creatinine cle arance, was 1.15 (95% CI, 1.02-1.30) for systolic pressure, 1.27 (95% CI, 1 .01-1.60) for diastolic pressure, and 1.30 (95% CI, 1.05-1.61) for mean art erial pressure. Supplemental analyser that did not include death as a failu re event or reduce the minimum allograft survival time for study subjects t o 6 months yielded results consistent with the primary analysis. There was no evidence of modification of the blood pressure-allograft failure relatio nship by ethnicity or diabetes mellitus. Conclusions Systolic, diastolic, and mean arterial blood pressures at 1 yea r posttransplantation strongly predict allograft survival adjusted for base line renal function. More aggressive control of blood pressure may prolong cadaveric allograft survival.