Depression and mortality have been studied separately in patients with coronary heart disease (CHD) and in populations healthy at study inception. This does not allow comparisons across risk-factor groups based on the cross-classification of depression and CHD status. We prospectively examined the effects of depressive symptoms, assessed in 2002-2004, on all-cause and cardiovascular -mortality in a large sample of 5936 middle-aged participants, with and without established CHD, followed over 5.6 years

We created 4-risk-factor groups based on the cross classification of depressive symptoms and CHD status. The age-and-sex-adjusted hazard ratios for all causes death were 1.67-fold (p< 0.05) higher for participants with only CHD, 2.10-fold (p< 0.001) higher for those with only depressive symptoms and 4.99-fold (p< 0.001) higher for those with both CHD and depressive symptoms when compared to participants without either condition. The two latter risk-factor groups remained at increased risk after adjustments for relevant confounders. Further comparisons indicated that the risks of all-cause death were also higher, but to a lesser extent, for participants with both depressive-symptoms and CHD when compared to those with only one of these conditions. These associations were also observed for cardiovascular mortality

This study provides evidence that depressive symptoms are associated with an increased risk of all-cause and CVD death and that this risk is particularly marked in depressive participants with co-morbid CHD. Several clinical guidelines have recommended screening, referral, and treatment of depression in primary and cardiovascular care units. These findings suggest that these recommendations need further consideration.