Specialty of ambulatory care physicians and mortality among elderly patients after myocardial infarction

Background: The outcome after myocardial infarction may be influenced by the type of physician providing ambulatory care. Methods: We studied 35,520 patients 65 years of age or older who were hospitalized for myocardial infarction in seven states during 1994 and 1995 and who survived for at least three months after discharge. From Medicare claims, we identified ambulatory visits to cardiologists, internists, and family practitioners. Using propensity scores to adjust for demographic, clinical, and hospital characteristics, we analyzed treatment and mortality at two years among patients matched according to their estimated propensity to receive care from a cardiologist within three months after discharge. Results: As compared with patients who saw only an internist or a family practitioner in the three months after discharge, patients who saw a cardiologist were younger, were more likely to be white, were more likely to be male, had fewer coexisting conditions, and were more likely to have undergone invasive cardiac procedures while hospitalized (P<0.01 for all comparisons). Patients who saw a cardiologist were more likely to undergo cardiac procedures and rehabilitation after discharge. Patients who saw a cardiologist had a lower two-year mortality rate than matched patients who saw only an internist or a family practitioner (14.6 percent vs. 18.3 percent, P<0.001). Patients who saw both a cardiologist and an internist or a family practitioner had a lower mortality rate than matched patients who saw only a cardiologist (11.1 percent vs. 12.1 percent, P=0.02). Conclusions: Ambulatory visits to cardiologists were associated with greater use of cardiac procedures and decreased mortality after myocardial infarction. Concurrent care by an internist or a family practitioner was associated with a further reduction in mortality.