Affiliation:
1. Daini Hattori Clinic Tokyo Japan
2. Division of Nephrology and Hypertension, Department of Internal Medicine St. Marianna University School of Medicine Kawasaki Japan
3. Division of Nephrology, Department of Internal Medicine Showa University Fujigaoka Hospital Yokohama Japan
4. Showa University Research Administration Center (SURAC) Tokyo Japan
Abstract
AbstractIntroductionThis systematic review and meta‐analysis examined the relationship between hyponatremia and worse outcomes in patients undergoing maintenance hemodialysis.MethodsThe MEDLINE, EMBASE, CENTRAL, and Web of Science databases were used to search for relevant articles. The target population was patients on maintenance hemodialysis (those undergoing hemodialysis for ≥60 days). The defined outcomes were death, cardiovascular disease, cognitive decline, and falls. Meta‐analysis was performed with a random‐effects model of pairwise comparisons of normonatremia and hyponatremia defined for each study, 1‐mmol/L increment of sodium analysis, and dose–response analysis using the sodium concentration defined for each study. This study was registered with PROSPERO (registration number CRD42018087667).ResultsThirteen articles were included. The pairwise analysis revealed that the hazard ratio for all‐cause mortality was 1.45 (95% confidence interval, 1.31–1.61). The analysis of 1‐mmol/L increment of sodium included six studies with a hazard ratio for all‐cause mortality of 0.94 (95% confidence interval, 0.91–0.97) for each 1‐mmol/L increase in the serum sodium concentration. In the dose–response analysis, assuming a linear relationship, a sodium increment of 1 mmol/L revealed a hazard ratio for all‐cause mortality of 0.97 (95% confidence interval, 0.96–0.98). Other outcomes could not be integrated.ConclusionsHyponatremia is associated with all‐cause mortality in patients undergoing maintenance hemodialysis. Healthcare providers should pay special attention to even the slightest indication of hyponatremia.