Impaired fasting glucose and recurrent cardiovascular disease among survivors of a first acute myocardial infarction: evidence of a sex difference? The Western New York experience.

BACKGROUND AND AIMS

There is little epidemiological evidence regarding the association of impaired glucose metabolism with recurrent cardiovascular events. We therefore examined potential sex differences in the effect of impaired fasting glucose (IFG) on recurrent cardiovascular disease (CVD) in a community-based study of survivors of a first acute myocardial infarction (MI).

METHODS AND RESULTS

This report focuses on 1226 incident MI cases (28.4% women) discharged alive from area hospitals in the Western New York Acute MI Study (1996-2004). Deaths and underlying cause of death were determined via query of the National Death Index (Plus) Retrieval Program with follow-up through December 31, 2004. Outcomes reported included fatal or non-fatal coronary heart disease (CHD) or coronary revascularization surgery and total stroke. Traditional CHD risk factors and other explanatory variables were determined by clinical examination after the first acute event. Impaired fasting glucose was defined as fasting blood glucose between 100 and 125mg/dl. During a mean follow-up of 4.5 years, there were 91 recurrent events (26.1%) in women and 173 recurrent events (19.7%) in men. After multivariable adjustment, the hazard ratios for recurrent cardiovascular events were 1.96 (95% CI: 1.15-3.16) and 2.59 (1.56-4.30) in women with IFG and with diabetes, respectively, compared to normoglycemic women. Among men, neither IFG nor diabetes was independently related to risk of recurrence.

CONCLUSIONS

In this study, IFG was a strong risk factor for recurrent cardiovascular events only among women. These results suggest that increased cardiovascular risk in MI survivors begins at lower glucose levels in women than men.