Peridialysis BP levels and risk of all-cause mortality: a dose-response meta-analysis

Blood pressure (BP) management posed great challenge in hemodialysis (HD) population. We conducted a dose-response meta-analysis to investigate the quantitative features and the potential threshold effect of the associations between peridialysis BP levels and all-cause mortality risk in HD population. We searched all of the prospective cohort studies (published before 18 March 2017) on the associations between peridialysis BP levels and all-cause mortality risk. A total of 229,688 prevalent HD patients from 8 studies were included. Significant non-linear associations were noted between peridialytic BP levels and all-cause mortality risk. Significant increased risk of death was found in four peridialysis BP ranges, that is, low levels of predialysis SBP (<135 mmHg, 140 mmHg as the reference), two extremes of predialysis DBP (<55 and >95 mmHg, 90 mmHg as the reference), high levels of postdialysis SBP (>180 mmHg, 130 mmHg as the reference), and low levels of postdialysis DBP (<75 mmHg, 80 mmHg as the reference). Threshold effect was determined in the associations between peridialysis BP and all-cause mortality risk, and potential BP thresholds were identified (149 mmHg for predialysis SBP, 79 mmHg for predialysis DBP, 147 mmHg for postdialysis SBP and 76 mmHg for postdialysis DBP). In conclusion, the proposed peridialysis BP ranges and the threshold values could help clinicians identify high risk HD patients. The interpretation of the peridialysis BP mortality associations should be based on the features of HD population (especially the cardiovascular conditions, volume status and the dialysis vintage).