Depression following myocardial infarction. Impact on 6-month survival.
This study found that major depression following a myocardial infarction (MI) is an independent risk factor for mortality at 6 months.
- N=222 adults (78% male, mean age 60) who suffered an MI and survived to be discharged were followed for 6 months.
- A baseline interview was conducted 5-15 days after MI that included social and demographic data, smoking status, and data to establish a DSM-III-R diagnosis of major depression (modified to establish that symptoms had been present every day since admission, not the usual 2 weeks).
- Hospital charts were reviewed for cardiac history and measures (previous MI, left ventricular ejection fraction, etc).
- Setting: university-affiliated hospital specializing in cardiac care in Montreal, from 1991-1992.
- Primary outcome: survival at 6 months.
- 35 patients (16%) met the modified criteria for DSM-III-R major depressive disorder.
- 12 patients had died by 6 months post-MI, all due to cardiac causes, and six of whom had met criteria for depression. Thus, mortality rate at 6 months was 17% (6/35) for depressed patients, compared with 3% (6/187) for nondepressed patients.
- Depression significantly predicted mortality (hazard ratio 5.74, 95% CI 4.61-6.87, P=0.0006). This remained significant after controlling for other predictors of mortality (left ventricular dysfunction, previous MI, etc.) The adjusted hazard ratio was 4.29 (95% CI 3.14-5.44, P=0.013).
Frasure-Smith N, Lespérance F, Talajic M. Depression following myocardial infarction. Impact on 6-month survival. JAMA. 1993;270(15):1819-1825.