Supplementary Material for: Blood Pressure Variability and Outcomes in End-Stage Renal Disease Patients on Dialysis: A Systematic Review and Meta-Analysis

Objective: Previous studies have suggested that blood pressure variability (BPV) is associated with an increased risk of mortality and cardiovascular events in patients on dialysis. However, the results are inconsistent. A comprehensive literature review was conducted to analyze the association between BPV and outcomes in patients on dialysis. Methods: Articles in Embase, Medline, and Web of Science from the date of inception through January 1, 2020, were identified. The outcomes were all-cause and cardiovascular mortality and cardiovascular events. The risk of bias was assessed using the Newcastle-Ottawa scale tool. Random effects models were used to pool the overall effect sizes. Two reviewers extracted the data independently. Meta-regression and subgroup analyses were performed to explore potential heterogeneity. Results: Fifteen eligible studies were included, and all enrolled hemodialysis recipients only. The overall risk of bias for the included studies was low. A 1-SD increase in systolic BPV was associated with higher risks of all-cause mortality (HR = 1.18; 95% CI 1.11–1.26, I2 = 53.8%), cardiovascular mortality (HR = 1.23; 95% CI 1.10–1.37, I2 = 57.2%), and cardiovascular events (HR = 1.27; 95% CI 1.07–1.51, I2 = 69.3%). Likewise, a 1-SD increase in diastolic BPV was associated with higher HR for all-cause and cardiovascular mortality (HR = 1.14; 95% CI 1.05–1.23, I2 = 0.0%, and HR = 1.14; 95% CI 0.94–1.38, I2 = 0.0%, respectively). Conclusions: A greater BPV is associated with higher risks of cardiovascular and mortality outcomes in patients on hemodialysis. Further research is required to determine whether BPV may be useful either as a marker enabling individualized treatment of cardiovascular risk or as a treatment target in its own right.