Association of depression with all-cause and cardiovascular mortality among maintenance hemodialysis patients in China: a retrospective cohort study.

BACKGROUND

Depression is not uncommon among patients with end-stage renal disease being treated by hemodialysis (HD). However, the relationship between depression and mortality is inconclusive. This study aims to investigate the above relationship in maintenance hemodialysis (MHD) patients.

METHODS

We conducted a retrospective cohort study involving 746 adults who were treated with long-term HD within a single dialysis center. Depression was assessed with the self-reported Patient Health Questionnaire-9 (PHQ-9). Kaplan-Meier survival analysis, multivariable Cox regression models, restricted cubic splines, subgroup and sensitivity analyses were used to assess the relationship between depression and mortality risks.

RESULTS

Among 746 patients (median follow-up: 30.47 months), 211 deaths (28.28 %) occurred, including 149 (19.97 %) cardiovascular deaths. Compared to the non-depression group, the depression was positively associated with all-cause mortality (HR = 1.34, 95 % = 1.01-1.77) and cardiovascular mortality (HR = 1.55, 95 % = 1.11-2.17) after multivariate adjustments. Similarly, we detected a significant positive association when PHQ-9 score was a continuous variable. Besides, the risk of all-cause and cardiovascular mortality in MHD patients increased by 13 % (HR = 1.13, 95 %CI = 1.00-1.27) and by 19 % (HR = 1.19, 95 %CI = 1.03-1.36) for each standard deviation increase in PHQ-9 score, respectively. The findings were robust in all the subgroup and sensitivity analyses. Kaplan-Meier analysis revealed significantly lower cumulative survival in the depression group compared to the non-depression group (p < 0.05). Furthermore, a positive linear dose-response relationship was observed between PHQ-9 scores and the risk of all-cause and cardiovascular mortality (pnon-linearity > 0.05).

CONCLUSIONS

Depression is a heterogeneous disorder and may be associated with increased mortality for MHD patients. Future research needs to assess whether early identification and treatment of depression may help to improve quality of life and survival in MHD patients.