Nocturnal blood pressure and 24-hour pulse pressure are potent indicators of mortality in hemodialysis patients

BACKGROUND: Cardiovascular (CV) complications are the leading cause of mortality in hemodialysis patients. The role of arterial hypertension on the prognosis of CV in hemodialysis patients is not as clear as in the general population. The purpose of this study was to investigate the prognostic role of ambulatory blood pressure (BP) on CV mortality in treated hypertensive hemodialysis patients. METHODS: Fifty-seven treated hypertensive hemodialysis patients (56.87 +/- 16.22 years, 30 men) were prospectively studied. All patients initially underwent an ambulatory BP monitoring between two dialysis sessions. The outcome event studied was CV death; kidney transplantation and deaths not related to CV disease were censored. RESULTS: The duration of follow-up was 34.4 +/- 20.39 months, during which 10 CV and 8 non-CV fatal events occurred. In the 10 patients who died from CV complications, age, previous CV events, ambulatory systolic BP, ambulatory pulse pressure (PP), and life-long smoking level were significantly higher, and the office diastolic BP was lower at the time of inclusion than in those who did not die from CV complications (N = 47). Based on Cox analysis and after adjustment for age, sex, and previous CV events, a low office diastolic BP relative risk (RR) 0.49, 95% CI, 0.25 to 0.93, P = 0.03], an elevated 24-hour PP (RR 1.85, 95% CI, 1.28 to 2.65, P = 0.009), and an elevated nocturnal systolic BP (RR 1.41, 95% CI, 1.08 to 1.84, P = 0.01) were predictors of CV mortality (RR associated with a 10 mm Hg increase in BP and in PP). CONCLUSION: This study demonstrates that nocturnal BP and 24-hour PP are independent predictors of CV mortality in treated hypertensive hemodialysis patients. Randomized trials are needed to investigate whether nocturnal BP and 24-hour PP are superior to office BP as targets for antihypertensive therapy in this high-risk group.