Analyzing the Impact of Depression on All-Cause Mortality in Different Sex and Age Groups: A 11-Year Follow-Up Study of Spanish Population

Background: Previous studies have shown that depression has a significant impact on all-cause mortality, particularly in men. However, the link between depression and mortality across different age and gender groups is inconsistent. This study aims to explore the relationship between depression and all-cause mortality in various age and gender categories within a Spanish national cohort, while also accounting for other influencing factors over an 11-year follow-up period. Methods: A nationally representative sample of the Spanish adult population ( n = 4,582) was followed up for 11 years. Kaplan-Meier estimates, unadjusted and adjusted Cox proportional hazard regression models were conducted to test whether baseline depression and sociodemographic characteristics (educational level, low income, marital status, feelings of loneliness, alcohol and tobacco use, and having chronic conditions) were associated with all-cause mortality for different gender and age-specific groups, separately. Results: Unadjusted analysis by age and gender indicated that depression had a significant relationship with all-cause mortality in young-and-middle-aged women (HR = 1.75; p