Association between frailty and adverse outcomes in patients undergoing maintenance hemodialysis: a systematic review and meta-analysis

Objectives: The aim of this study was to determine the strength of the association between frailty and adverse outcomes in patients undergoing maintenance hemodialysis. Design: A systematic review and meta-analysis. Setting and participants: Patients aged >= 18 years who were undergoing maintenance hemodialysis. Methods: PubMed, Web of Science, Embase, the Cochrane Library, Scopus, the China Knowledge Resource Integrated Database, the Wanfang Database and the Weipu Database were searched from inception until 11 April 2024. The reviewers independently selected the studies, extracted the data and evaluated the quality of the studies. Stata 15.1 software was used to perform the meta-analysis. Results: A total of 36 articles were included in this study, including 56,867 patients. The primary outcome events in this study were mortality, hospitalization, and vascular access events. The secondary outcomes were depression, cognitive impairment, falls, fracture, sleep disturbances, and quality of life. This study suggested that frailty was associated with mortality in patients undergoing maintenance hemodialysis [hazard ratio (HR), 1.97; 95% CI, 1.62-2.40]. Frailty increased the risk of mortality in patients [odds ratio (OR), 2.33; 95% CI, 1.47-3.68]. In addition, we found that frailty was significantly associated with hospitalization in patients undergoing maintenance hemodialysis (OR, 2.47; 95% CI, 1.52-4.03). Patients who were undergoing maintenance hemodialysis and who were frail had a greater risk of hospitalization [RR, 1.47; 95% CI, 1.05-2.08] and emergency visits (RR, 2.28; 95% CI, 1.78-2.92). The results of this study also suggested that frailty was associated with a greater risk of vascular access events (HR, 1.72; 95% CI, 1.50-1.97). Finally, frailty increased the risk of depression (OR, 4.31; 95% CI, 1.83-10.18), falls and fractures, and reduced quality of life. Conclusions: The findings of this study suggested that frailty was an important predictor of adverse outcomes in patients undergoing maintenance hemodialysis. In the future, medical staff should regularly evaluate signs of weakness, formulate individual diagnosis and treatment plans, adjust dialysis plans according to the patient's condition, and reduce the occurrence of adverse events.