Influence of gender on short- and long term mortality after acute myocardial infarction

The aim of this study wets to assess differences in short-and long-term mortality between male and female patients with acute myocardial infarction (AMI). The study population consisted of 6,676 consecutive patients admitted alive with an enzyme-confirmed AMI to 27 Danish hospitals from 1990 to 1992. Five patients were excluded because of missing information. Female patients (n = 2,170) were on average 5 years older than male patients (n = 4,501, p <0.001), had lower body mass index, and more often had diabetes, hypertension, and congestive heart failure. Left ventricular systolic function was the same for men and women. Women received thrombolytic therapy less often. The 1-year mortality for female patients was 28 +/- 1% and far men 21 +/- 1% (p < 0.001). The unadjusted risk ratio associated with male gender in a proportional-hazards model was 0.76 (95% confidence intervals [CI] 0.70 to 0.83). Adjustment for age removed the importance of gender, and the risk ratio associated with male gender was 1.06 (95% CI 0.97 to 1.2, p = 0.2). An introduction of further variables in the model did not change this. Subdividing mortality into 6-day, 30-day, and late mortality demonstrated a significantly increased mortality in women in the short-term (6 and 30 days), with a risk ratio in men of 0.58 (95% CI 0.42 to 0.81) and 0.80 (95% Cl 0.65 to 0.99), respectively. From day 30 onward there was an increased mortality in men with ct risk ratio of 1.16 (95% Cl 1.03 to 1.31, p = 0.01). Thus, women admitted alive to the hospital with an AMI have on increased long-term mortality that is explained by their older age. However, short-term mortality in women seems to increase independently of other risk factors, but is later followed by on increase in mortality in men.