Hypertension in the haemodialysis population: any relationship to 2-years survival?

Background. Few studies have quantified the effect of hypertension on survi val in the haemodialysis (HD) population. We have previously reported lack of adverse effect of hypertension on 1-year mortality in a cohort of 649 ha emodialysis patients (Am J Kidney Dis 1996; 28. 737-744). We report here th e effect of hypertension on 2-year survival in the same cohort of patients. Methods. We reviewed the complete computerized files on 649 HD patients enr olled in 10 haemodialysis centres in the state of Mississippi, USA. One-mon th dialysis records for each patient from mid-October 1994 to mid-November 1994 were reviewed. Predialysis mean arterial pressure was calculated as im mediate predialysis diastolic pressure plus one-third the difference betwee n systolic and diastolic pressure. Patients were classified as hypertensive if their average pre-MAP was more than 114 mmHg or they were receiving ant ihypertensive drugs during the study period. Normotensives had a pre-MAP <1 14 and were not receiving any antihypertensives. We followed these patients for 2 years to determine their survival and the effect of their BP status, as determined in October 1994, on 2-year mortality. Results. In univariate analysis, hypertension was associated with improved 2-years survival (relative risk 0.64, P = 008 compared to normotensives). F urthermore, among the hypertensives, good blood pressure control (less than 140/90) was associated with increased relative risk of death at 2 years (R R 1.86, P = 0.004). In multivariate analysis, taking age, race, serum album in, and diabetic status into consideration, there was a 27% reduction in mo rtality among hypertensives compared to normtensives (RR 0.73, P = 0.06). O ther factors of significance in multivariate analysis were age (RR 1.03/yea r, P = 0.02), serum albumin (RR 0.36/g, P < 0.0001), diabetes mellitus (RR 1.35, P = 0.07), and race (RR 0.64, P = 0.05). Conclusions. Our study suggests that hypertension has no adverse effect on survival at 2 years in the haemodialysis population.