Functional recovery after myocardial infarction in men: The independent effects of social class

Background: Social class has been repeatedly associated with cardiovascular-related illness and death, but no studies have examined the effect of social class on recovery from myocardial infarction. Moreover, few studies have simultaneously evaluated a broad array of demographic, clinical, and psychosocial factors that may influence health outcomes after myocardial infarction. Objective: To determine whether social class remains independently associated with functional recovery after myocardial infarction, even after controlling for clinical, demographic, and psychosocial factors known to influence outcomes after infarction. Design: Analysis of prospective data from a multicenter, randomized, double-blind clinical trial. Setting: 25 hospitals or clinical settings in the United States and Canada that participated in the Beta Blocker Heart Attack Trial, including the Health Insurance Plan substudy. Patients: 2145 men 29 to 69 years of age who were hospitalized with acute myocardial infarction and were recruited into the Beta Blocker Heart Attack Trial. Measurements: The primary outcome was change in New York Heart Association functional class between baseline assessment and 12 months after infarction, dichotomized as improved or not improved (that is, no change, decline in at least one category, or death). Results: Social class maintained its independent effect on improved functional status, even after controlling for pertinent prognostic factors. Persons of high social class were significantly more likely than persons of low or middle social class to have improved functional status 1 year after infarction. Certain clinical, demographic, and psychosocial features were related to recovery, but the effect of social class could not be explained by these additional features. Conclusions: Social class has a substantial influence on recovery from myocardial infarction and may explain differences in clinical outcomes.