In-Center Nocturnal Hemodialysis Versus Conventional Hemodialysis: A Systematic Review of the Evidence

Background: Owing to its longer treatment duration-up to 8 hours per dialysis treatment-in-center thrice-weekly nocturnal hemodialysis (HD) is receiving greater attention. To better understand the evidence for in-center nocturnal HD, we sought to systematically review the literature to determine the effects of in-center nocturnal HD versus conventional HD on clinically relevant outcomes. Study Design: We searched MEDLINE, Embase, Evidence-Based Medicine Reviews (EBMR), Web of Science, and Scopus from the earliest date in the database to November 2016. Setting & Population: Adults receiving in-center nocturnal HD compared with those receiving conventional HD. Selection Criteria for Studies: All quasi-experimental and observational studies were considered; randomized trials were sought but not found. Predictor: Nocturnal vs conventional in-center HD. Outcomes: Indexes of blood pressure and left ventricular hypertrophy, markers of anemia, measures of bone mineral metabolism, nutrition, quality of life, sleep quality, episodes of intradialytic hypotension, hospitalization, and mortality. Results: Of 2,086 identified citations, 21 met the inclusion criteria, comprising a total of 1,165 in-center nocturnal HD patients and 15,865 conventional HD patients. Although there was substantial heterogeneity in reporting of outcomes, we pooled data for measures of blood pressure, anemia, and mineral metabolism. Though heterogeneity was generally high, in-center nocturnal HD was associated with improved systolic blood pressure (-3.18 [95% CI, -5.58 to -0.78) mm Hg, increased hemoglobin levels (0.53 [95% CI, 0.11-0.94] g/dL), and lower serum phosphate levels (-0.97 [95% CI, -1.48 to -0.46] mg/dL). Limitations: No randomized trials have been conducted to address the clinical effects of in-center nocturnal HD. The quality of the observational literature contributing to the results of this review was generally poor to moderate. Confounded outcomes are a significant concern. Publication bias and outcome reporting bias remain possibilities. Conclusions: Relative to conventional HD, in-center nocturnal HD was associated with improvements in several clinically relevant outcomes. Other benefits may not have been detected due to small sample sizes of included studies; no prespecified outcome was worse with in-center nocturnal HD. (C) 2017 Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc.