Researchers at Washington University School of Medicine, St Louis, may have found the reason that depression in patients who have had a myocardial infarction (MI) increases the risk of death. The findings appear in the October 23 issue of Circulation: Journal of the American Heart Association.
The investigators studied a subset of participants in the Enhancing Recovery in Coronary Heart Disease (ENRICHED) clinical trial of patients admitted to coronary care units between 1997 and 2000. Using criteria in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, 307 patients with MI were diagnosed as having major or minor depression and 366 as having neither. All had had an MI in the 28 days before joining the trial. Each underwent 24-hour ambulatory electrocardiographic monitoring after hospital discharge to assess heart rate variability (HRV), a measure of cardiac autonomic function, including sympathetic and parasympathetic nervous systems. Low HRV reflects excessive sympathetic or reduced parasympathetic function and is a strong independent predictor of post-MI death.
Mitka M. Depression and MI Deaths. JAMA. 2001;286(20):2534. doi:10.1001/jama.286.20.2534