DEPRESSION FOLLOWING MYOCARDIAL-INFARCTION - IMPACT ON 6-MONTH SURVIVAL

Objective.-To determine if the diagnosis of major depression in patien ts hospitalized following myocardial infarction (MI) would have an ind ependent impact on cardiac mortality over the first 6 months after dis charge. Design.-Prospective evaluation of the impact of depression ass essed using a modified version of the National Institute of Mental Hea lth Diagnostic Interview Schedule for major depressive episode. Cox pr oportional hazards regression was used to evaluate the independent imp act of depression after control for significant clinical predictors in the data set. Setting.-A large, university-affiliated hospital specia lizing in cardiac care, located in Montreal, Quebec. Patients.-All con senting patients (N=222) who met established criteria for MI between A ugust 1991 and July 1992 and who survived to be discharged from the ho spital. Patients were interviewed between 5 and 15 days following the MI and were followed up for 6 months. There were no age limits (range, 24 to 88 years; mean, 60 years). The sample was 78% male. Primary Out come Measure.-Survival status at 6 months. Results.-By 6 months, 12 pa tients had died. All deaths were due to cardiac causes. Depression was a significant predictor of mortality (hazard ratio, 5.74; 95% confide nce interval, 4.61 to 6.87; P=.0006). The impact of depression remaine d after control for left ventricular dysfunction (Killip class) and pr evious MI, the multivariate significant predictors of mortality in the data set (adjusted hazard ratio, 4.29; 95% confidence interval, 3.14 to 5.44; P=.013). Conclusion.-Major depression in patients hospitalize d following an MI is an independent risk factor for mortality at 6 mon ths. Its impact is at least equivalent to that of left ventricular dys function (Killip class) and history of previous MI. Additional study i s needed to determine whether treatment of depression can influence po st-MI survival and to assess possible underlying mechanisms.