Women younger than 65 years with diabetes mellitus are a high-risk group after myocardial infarction: a report from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admission (RIKS-HIA)

Abstract

Objective: To analyse gender differences in prognosis, risk factors and evidence-based treatment in patients with diabetes and myocardial infarction.

Methods: Mortality in 1995–2002 was analysed in 70 882 Swedish patients (age <80) with a first registry-recorded acute myocardial infarction stratified by gender and age. Owing to gender differences in mortality, specifically characterising patients below the age of 65 years, a more detailed analysis was performed within this cohort of 25 555 patients. In this group, 5786 (23%) were women and 4473 (18%) had diabetes. Differences in clinical and other parameters were adjusted for using a propensity score model.

Results: Long-term mortality in diabetic patients aged <65 years was significantly higher in women than men (RR 1.34; 95% CI 1.16 to 1.55). Compared with diabetic men, women had an increased risk factor burden (hypertension 49 vs 43%; RR 1.12; 95% CI 1.05 to 1.20; heart failure 10 vs 8%; RR 1.25; 95% CI 1.03 to 1.53). Diabetic women aged <65 years were less frequently treated with intravenous β-blockade during the acute hospital phase and with angiotensin-converting enzyme inhibitors at hospital discharge. However, this under-use was not associated with the mortality differences, nor was female gender by itself.

Conclusion: Women below 65 years of age with diabetes have a poorer outcome than men after a myocardial infarction. This relates to an increased risk factor burden. It is suggested that greater awareness of this situation and improved prevention have the potential to improve what is an unfavourable situation for these women.