Importance: Depression is associated with increased disease burden worldwide and with higher risk of mortality in Western populations.
Objective: To investigate whether depression is a risk factor for all-cause and cardiovascular disease (CVD) mortality in adults in China.
Design, setting, and participants: This cohort study prospectively followed adults aged 30 to 79 years in the China Kadoorie Biobank (CKB) study from June 1, 2004, to December 31, 2016, and adults aged 32 to 104 years in the Dongfeng-Tongji (DFTJ) study from September 1, 2008, to December 31, 2016. Data analysis was conducted from June 1, 2018, to March 31, 2019.
Main outcomes and measures: Depression was evaluated using the Chinese version of the World Health Organization Composite International Diagnostic Interview-Short Form in the CKB cohort and a 7-item symptoms questionnaire modified from the Composite International Diagnostic Interview-Short Form in the DFTJ cohort. Multivariable-adjusted Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% CIs for the association of depression with mortality. Covariates in the final models included sociodemographic characteristics, lifestyle factors, and personal and family medical history.
Results: Among 512 712 individuals (mean [SD] age, 52.0 [10.7] years; 302 509 [59.0%] women) in the CKB cohort, there were 44 065 deaths, including 18 273 CVD deaths. The 12-month prevalence of major depressive episode in the CKB cohort was 0.64%, and the 1-month prevalence of clinically significant depressive symptoms was 17.96% in the DFTJ cohort. Among 26 298 individuals (mean [SD] age, 63.6 [7.8] years; 14 508 [55.2%] women) in the DFTJ cohort, there were 2571 deaths, including 1013 CVD deaths. In the multivariable-adjusted model, depression was associated with increased risk of all-cause mortality (CKB cohort: HR, 1.32 [95% CI, 1.20-1.46]; P < .001; DFTJ cohort: HR, 1.17 [95% CI, 1.06-1.29]; P = .002) and CVD mortality (CKB cohort: HR, 1.22 [95% CI, 1.04-1.44]; P = .02; DFTJ cohort: HR, 1.32 [95% CI, 1.14-1.54]; P < .001). In both cohorts, men had statistically significantly higher risk of all-cause mortality (CKB cohort: HR, 1.53 [95% CI, 1.32-1.76]; DFTJ cohort: HR, 1.24 [95% CI, 1.10-1.41]) and CVD mortality (CKB cohort: HR, 1.39 [95% CI, 1.10-1.76]; DFTJ cohort: HR, 1.49 [95% CI, 1.23-1.80]), while the association of depression with mortality among women was only significant for all-cause mortality in the CKB cohort (HR, 1.19 [95% CI, 1.03-1.37]).
Conclusions and relevance: These findings suggest that depression is associated with an increased risk of all-cause and CVD mortality in adults in China, particularly in men. These findings highlight the importance and urgency of depression management as a measure for preventing premature deaths in China.