Objective: To determine sex differences in survival after myocardial infarction in older individuals.
Design: Prospective cohort study based on a community sample of older individuals. All patients were followed for 1 year after hospital admission.
Setting: Two hospitals in New Haven, Connecticut.
Participants: The study included 103 women and 120 men who were participants in the New Haven, CT cohort of the Established Populations for the Epidemiologic Study of the Elderly (EPESE) program and who were diagnosed with myocardial infarction between the inception of the community study in 1982 and December 31, 1992. The mean age of women was 79.3 and of men, 77.3.
Measurements: Data on clinical characteristics were abstracted from medical records. Sociodemographic, psychosocial, and physical function information was derived from the EPESE interview preceding the infarction. The main outcome measure was all-cause mortality, for which three end points were used: early mortality (first 30 days), late mortality (1-year mortality among survivors of the first 30 days), and overall mortality (1-year mortality from admission in the whole sample).
Results: Mortality in the first 30 days did not differ significantly in the two sexes. The relative risk (RR) of death in women compared with men was 0.85 (95% confidence interval [CI], 0.49-1.47) before multivariable adjustment; this was unchanged after adjustment for demographic factors, comorbidity, functional status, psychosocial factors, and clinical severity (RR, 0.85, 95% CI, 0.41-1.76). Among survivors of 30 days, women were almost two times more likely to survive at 1 year compared with men, both before multivariable adjustment (RR, 0.56, 95% CI, 0.31-1.02) and after controlling for demographic factors, comorbidity, physical function, psychosocial factors, clinical severity on admission, and hospital complications (RR, 0.44 ; 95% CI, 0.20-0.99). Analyses involving 1-year follow-up from admission for the entire sample yielded intermediate results.
Conclusion: There was little difference in mortality in the first 30 days after myocardial infarction between older men and women, but when the early deaths were excluded, women showed an increased survival compared with men in the first year after the myocardial infarction.