Depression and health-care costs during the first year following myocardial infarction

Depression in the hospital after myocardial infarction (MI) has been associated with a substantial increase in the long-term risk of cardiac mortality, but little is known about other outcomes. This study uses Quebec Medicare data to examine the relationship between post-MI depression and physician costs, including both out-patient care and hospital readmissions.

The sample consists of 848 1-year survivors of an acute MI who had completed the Beck Depression Inventory (BDI) in hospital. Two hundred sixty subjects had BDI scores of >/=10 (30.7%), indicative of mild to moderate symptoms of depression. Quebec Medicare data during the index admission for an acute MI and during the year following discharge were compared for the patients with elevated BDI scores and those with normal scores.

Total costs, in Canadian dollars (out-patient physician charges plus physician costs during admissions plus estimates of associated direct costs), were about 41% higher (p = 0.004) for patients with elevated BDI scores. The difference was primarily related to out-patient and emergency room visits and readmission costs associated with longer stays in hospital wards, and was not accounted for by use of psychiatric services or readmissions for revascularization.

Results suggest that, in addition to the survival risks associated with post-MI depression, there are increased health care costs linked to both readmissions and out-patient contacts among depressed patients who survive the first post-MI year. The extent to which the increased use of health care may have reduced depression and enhanced survival remains unclear.