Survival of patients who opt for dialysis versus conservative care: a systematic review and meta-analysis

Background Non-dialytic conservative care (CC) has been proposed as a treatment option for patients with kidney failure. This systematic review and meta-analysis aims to compare survival outcomes between dialysis and CC in studies where patients made an explicit treatment choice. Methods Five databases were systematically searched from origin up to February 25th, 2021 for studies comparing survival outcomes among patients choosing dialysis versus CC. Adjusted and unadjusted survival rates were extracted and meta-analysis performed where applicable. Risk of bias analysis was performed according to the Cochrane Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I). Results Twenty-two cohort studies were included covering 21,344 patients. Most studies were prone to selection bias and confounding. Patients opting for dialysis were generally younger, had less comorbid conditions, functional impairments and frailty than patients who chose CC. Unadjusted median survival from treatment decision or eGFR <15mL/min/1.73m2 ranged between 20-67 months for dialysis and 6-31 months for CC. Meta-analysis of twelve studies that provided adjusted hazard ratios (HRs) for mortality showed a pooled adjusted HR of 0.47 (95% CI 0.39-0.57) for patients choosing dialysis compared to CC. In subgroups of patients with higher age or severe comorbidities, the reduction of mortality risk remained statistically significant, although analyses were unadjusted. Conclusions Patients opting for dialysis have an overall lower mortality risk compared to patients opting for CC. However, high risk of bias and heterogeneous reporting preclude definitive conclusions and results cannot be translated to an individual level.