Depressive symptoms and dispositional optimism in relation to mortality in older post-myocardial infarction patients

Mental well-being, characterized by low depressive symptoms and high dispositional optimism, is a protective factor against (cardiovascular) mortality in the general population. We aimed to assess whether such a relationship is also present in patients who have a history of MI, and whether it is independent of classic CVD risk factors. A secondary analysis of the Alpha Omega Trial cohort study was carried out, including 3566 patients with MI in their medical history and a mean follow-up period of 9.0 (SD 2.6) years. The 4Q and GDS were analysed in relation to (cause-specific) mortality using Cox proportionalhazards models adjusted for demographic and classic CVD risk factors. Patients were on average 71.2 years old (SD 5.4), and 20.5% were women. During the follow-up period, there were 1,219 deaths of which 448 (46.7%) as a result of CVD. For the allcause and CVD mortality, the multivariate-adjusted HR for depressive symptoms was 1.85 and 1.90 for the upper tertile versus the lower tertile (95% CI: 1.47–2.33; P for trend <0.001; and 95%CI: 1.31–2.76; P for trend <0.001). For non-cardiovascular/non-cancer mortality the relationship was even stronger (HR 2.16; 95% CI: 1.51–3.09; P for trend <0.001). Although similar protective trend relationships were observed for dispositional optimism, these were not independent of depressive symptoms. Depressive symptoms, rather than dispositional optimism, were independently predictive of all-cause, cardiovascular, and non-cardiovascular/non-cancer mortality in older post-MI patients.