There have been conflicting reports about differences in clinical outcomes and treatment among men and women who've had a myocardial infarction (MI). Most studies have focused on mortality, recurrent MI, or revascularization. Researchers investigated clinical outcomes in a large population-based cohort of patients presenting with their first MI. They focused on sex differences in the development of heart failure.

The patient population included all patients older than age 20 presenting with a primary diagnosis of MI during a 14-year period. The final cohort comprised 45,064 patients, of whom 24,737 had non-ST-segment elevation MI (NSTEMI) and 20,327 had ST-segment elevation MI (STEMI). Women constituted 34.3% and 26.5%, respectively, of these groups. Median follow-up was 6.2 years. The researchers note that women tended to be older, had more comorbidities, were seen less often by a cardiovascular specialist, and had lower rates of diagnostic angiography than men.

The unadjusted in-hospital death rate was higher among women who had STEMI or NSTEMI than it was among men. After adjustment for age, comorbidities, and other factors, this difference remained significant in patients who had STEMI but not in those who had NSTEMI. In both groups, women had a higher death rate than men after discharge. Women with STEMI and NSTEMI also had a higher rate of developing heart failure while in the hospital and after discharge.

The authors point out that there may be unmeasured confounders in an observational study such as this one. Also, it wasn't possible to adjust for patient or clinician preferences, they say. The authors note that they used a broad capture of the development of heart failure because symptom development and the future diagnosis of heart failure can be challenging in clinical practice.