Being male or having diabetes confers a poorer prognosis in patients with heart failure, a large meta-analysis in the European Journal of Heart Failure has shown.

The authors used data from 31 studies in the Meta-Analysis Global Group In Chronic Heart Failure (MAGGIC) of 41,949 patients with heart failure of which 28,052 were men and 13,897 women.

Survival analysis was performed to assess the association of gender with mortality, adjusting for mortality predictors such as: age; reduced or preserved ejection fraction (EF); and ischaemic or non-ischaemic aetiology. Patients were followed up for three years for mortality data.

The women studied were older than the men, 70.5 vs 65.6 years, with a higher incidence of hypertension, 49.9% vs 40.0%, but were less likely to have ischaemic heart disease, 46.3% vs 58.7%, and a reduced EF, 62.6% vs 81.6%.

Overall, 3,521 (25%) women and 7,232 (26%) men had died at three years and after adjustment, male gender was found to be an independent predictor of mortality. The better prognosis associated with female gender was more marked in patients with heart failure of non-ischaemic aetiology and in patients without diabetes.

The authors note that women with ischaemic heart failure present more like men probably because the effect of an acute event such as a myocardial infarction negates the degree of protection from being female unlike the more gradual process of a non-ischaemic cardiomyopathy. Furthermore, diabetes patients with heart failure are known to have a poorer prognosis and again less of a gender effect is seen.

The mechanism behind these findings is less clear but could simply be due to the female heart being stronger than its male counterpart. The authors also note that female hearts tend to remodel more favourably after infarction and that pregnancy can induce positive changes which can persist for many years postpartum.

Dr Peter Savill

• Martínez-Selles M, Doughty R N, Poppe K et al. Gender and survival in patients with heart failure: interactions with diabetes and aetiology. Results from the MAGGIC individual patient meta-analysis. Eur J Heart Fail 2012. DOI:10.1093/eurjhf/ hfs026