The relationship between all-cause mortality and depression in different gender and age groups of the Spanish population.

BACKGROUND:Literature has shown that the effect of depression on all-cause mortality is stronger in men. However, it is less clear whether depression affects older and younger people equally. The present study is aimed to analyze whether depression is associated to all-cause mortality in different age and gender groups. METHODS:We analyzed a nationally representative sample of the Spanish adult population that was followed-up on for a period of 6 years (n = 4583). Unadjusted and adjusted cox proportional hazard regression models were conducted to test whether baseline depression was associated to all-cause mortality in the total sample and in the different gender and age specific groups, separately. RESULTS:Unadjusted analyses revealed that depression was associated with higher likelihood of having a shorter survival and dying, in the total sample and in both groups of men (18-64 and 65+ years). However, adjusted analyses stratified by age groups and gender revealed that depression was only a significant factor for all-cause mortality in 18-64 aged men (HR: 6.11; 95%CI= 2.16,17.23). LIMITATIONS:Cause-specific mortality was not examined. Young adults and middle-aged participants were not analyzed separately. CONCLUSIONS:The depression and all-cause mortality relationship was only found among young and middle-aged men. Further studies should consider whether the significant association between depression and all-cause mortality in young and middle-aged men is due to a behavior of seeking help less, the way depression is shaped in adult men, or to other clinical or health-system related factors.