Interdialytic Blood Pressure and Risk of Cardiovascular Events and Death in Hemodialysis Patients

Abstract

Introduction: Normal (120-140 mm Hg) systolic peridialysis blood pressure (BP) is associated with higher mortality in hemodialysis (HD) patients.

Aim: We explored the relationship between hypertension and BP on outcomes using data collected at the interdialytic period.

Methods: This was a single-center observational cohort study with 2672 HD patients. BP was determined at inception, in mid-week, between 2 consecutive dialysis sessions. Hypertension was defined as systolic BP ≥ 140 mm Hg and/or diastolic BP ≥ 90 mm Hg. Endpoints were major CV events and all-cause mortality.

Results: During a median follow-up of 31 months, 761 patients (28%) experienced CV events and 1181 (44%) died. Hypertensive patients had lower survival free of CV than normotensive patients (P = 0.031). No difference occurred in the incidence of death between groups. Compared with the reference category of SBP ≥ 171 mmHg, the incidence of cardiovascular events was reduced in patients with SBP 101-110 (HR 0.647, 95% CI 0.455 to 0.920), 111-120 (HR 0.663, 95%CI 0.492 to 0.894), 121-130 (HR 0.747, 95%CI 0.569 to 0.981), and 131-140 (HR 0.757, 95%CI 0.596 to 0.962). On multivariate analysis, systolic and diastolic BP were not independent predictors of CV events or death. Normal interdialytic BP was not associated with mortality or CV events, and hypertension predicted an increased probability of CV complications.

Conclusions: Interdialytic BP may be preferred to guide treatment decisions, and HD patients should be treated according to guidelines for the general population until specific BP targets for this population are identified.

Keywords: Blood pressure; Chronic kidney disease; Hemodialysis; Hypertension.