Association Between Depression and Mortality in Patients Receiving Long-term Dialysis: A Systematic Review and Meta-analysis

Background We aimed to systematically review and analyze the association between depression and mortality risk in adults with kidney failure treated by long-term dialysis. Study Design A systematic review and meta-analysis of observational studies. Setting & Population Patients receiving long-term dialysis. Selection Criteria for Studies Searching MEDLINE, EMBASE, and PsycINFO, we identified studies examining the relationship between depression, measured as depressive symptoms or clinical diagnosis, and mortality. Predictor Depression status as determined by physician diagnosis or self-reported scales. Outcomes Pooled adjusted HR and OR of depression for all-cause mortality. Results 15 of 31 included studies showed a significant association between depression and mortality, including 5 of 6 studies with more than 6,000 participants. A significant link was established between the presence of depressive symptoms and mortality (HR, 1.51; 95% CI, 1.35-1.69; I2 = 40%) based on 12 studies reporting depressive symptoms using depression scales (N = 21,055; mean age, 57.6 years). After adjusting for potential publication bias, the presence of depressive symptoms remained a significant predictor of mortality (HR, 1.45; 95% CI, 1.27-1.65). In addition, combining across 6 studies reporting per-unit change in depression score (n = 7,857) resulted in a significant effect (HR per unit change in score, 1.04; 95% CI, 1.01-1.06; I2 = 74%). Limitations Depression or depressive symptoms were documented only from medical charts or a single self-report assessment. Included studies were heterogeneous because of variations in measurement methods, design, and analysis. Conclusions There is considerable between-study heterogeneity in reports of depressive symptoms in dialysis patients, likely caused by high variability in the way depressive symptoms are measured. However, the overall significant independent effect of depressive symptoms on survival of dialysis patients warrants studying the underlying mechanisms of this relationship and the potential benefits of interventions to improve depression on the outcomes.