# Blood Pressure Level and Risk of All-Cause Mortality in Patients With Kidney Failure on Maintenance Peritoneal Dialysis: A Systematic Review and Meta-Analysis of Observational Studies

## TL;DR

This study reviews existing research to understand how blood pressure affects the risk of death in patients with kidney failure undergoing peritoneal dialysis.

## Contribution

The paper provides a systematic review and meta-analysis of observational studies on blood pressure and mortality in peritoneal dialysis patients.

## Key findings

- Systolic BP >140 mm Hg was not significantly associated with higher mortality risk.
- Diastolic BP >90 mm Hg showed no association with mortality.
- The studies had high heterogeneity and risk of bias, limiting definitive conclusions.

## Abstract

To identify, appraise, and synthesize relevant epidemiologic studies to better understand the relations between blood pressure (BP) and outcomes in patients with kidney failure receiving maintenance peritoneal dialysis (PD) and to examine how the available evidence aligns with current clinical guidelines.

Systematic review and meta-analysis.

We conducted a comprehensive search of 5 databases (PubMed, Web of Science, Embase, CINAHL, Cochrane Library) through April 2023 (and abstracts from leading nephrology conferences from 2019-2023). Studies were eligible if they included patients receiving maintenance PD and reported associations between BP levels and all-cause mortality.

Systolic BP, diastolic BP, or presence/absence of hypertension.

All-cause mortality.

Dual independent screening and full-text review were performed. Where appropriate, data were then pooled using a random-effects meta-analysis. Adjusted data were not required for inclusion.

Thirty observational studies were included in the systematic review. Twenty-three studies were retrospective; 7 were prospective. Sixteen studies were single center, 13 were multicenter, and one study was unclear as it was presented only in abstract form. More than two-thirds were from Asia. Of the 28 full-length articles, only 9 had BP as the primary exposure, with the rest including BP only as a covariate in multivariable models. In the meta-analysis, compared with systolic BP 100-140 mm Hg, systolic BP >140 mm Hg was associated with a statistically nonsignificant 15% higher risk of all-cause mortality (RR, 1.15; 95% CI, 0.99-1.34). No association was found between diastolic BP >90 mm Hg (vs diastolic BP ≤90 mm Hg) and mortality (RR, 0.92; 95% CI, 0.53-1.57).

High level of heterogeneity and high risk of bias among the included studies.

The existing epidemiology literature is unable to offer definitive guidance regarding BP treatment targets for PD patients due to heterogeneity, risk of bias, and lack of statistical significance.

Some individual studies have reported that among patients with kidney failure treated with chronic peritoneal dialysis, higher blood pressure level is not correlated with higher risk of death, which differs from what is observed in the general population. However, experts continue to recommend lowering blood pressure as a treatment. We systematically reviewed and summarized the medical literature published before April 2023 concerning blood pressure level and risk of death among patients with kidney failure treated with chronic peritoneal dialysis. We found that the published studies have numerous limitations, and we concluded that more research is needed to generate better data to help physicians decide how to best manage blood pressure in this vulnerable high-risk population.