Depressive symptoms, frailty, and mortality among dialysis patients

Introduction: Frailty and depression are highly prevalent in the dialysis population, but the association between them, the risk factors for their development, and their independent associations with mortality have not been studied.

Methods: We examined 771 patients enrolled in the ACTIVE/ADIPOSE prevalent dialysis cohort study. Fried's frailty phenotype and the Center for Epidemiologic Studies Depression score were used to determine frailty and presence of depressive symptoms, respectively. We assessed the baseline association between frailty and depressive symptoms, whether one entity is a risk factor for development of the other, and associations between frailty and depressive symptoms with mortality.

Findings: At baseline, 13.1% of our population screened positive for depressive symptoms, 21.8% met criteria for frailty, and 10.0% met criteria for both. During follow-up, 26.6% of our population developed frailty and 12.7% developed depressive symptoms. Using multivariable logistic regression, baseline depressive symptoms were associated with 2.14-fold higher odds of being frail at baseline (95% confidence interval [CI] 1.45-3.17) and with a 2.16-fold higher odds of incident frailty during follow-up (95% CI 1.22-3.82). However, baseline frailty was not associated with incident depressive symptoms. Frailty and depressive symptoms were independent predictors of mortality in time-varying survival analysis (meeting frailty criteria: hazard ratio [HR] 1.53, 95% CI 1.05-2.23; depressive symptoms: HR 2.21, 95% CI 1.50-3.25).

Discussion: Frailty and depressive symptoms remained highly prevalent over time and were strongly associated with one another and independently associated with mortality among dialysis patients. Future studies should investigate whether interventions for depression could potentially mitigate the appearance of frailty and its associated poor outcomes.