Relation of sex to morbidity and mortality in patients with heart failure and reduced or preserved left ventricular ejection fraction.

Background: Previous studies indicate a survival advantage for women over men with chronic heart failure associated with reduced or preserved ejection fraction. Whether women with chronic heart failure are at less risk for hospitalization for worsening heart failure has not been well investigated.
Methods: Using data from the DIG trial, the relationship between sex and adverse outcomes, especially the risk of hospitalization for various causes, was evaluated in patients with reduced or preserved left ventricular ejection fraction.
Results: Survival was worse for men than women with either reduced (HR 1.48, 95% CI 1.33-1.65, P < .001) or preserved ejection fraction (HR 1.60, 95% CI 1.20-2.13, P = .001), with P =.406 for sex interaction. In contrast, the risk of hospitalization for heart failure was greater in men than women when ejection fraction was reduced (HR 1.19, 95% CI 1.07-1.33, P = .001) but not preserved (HR 0.90, 95% CI 0.67-1.22, P = .494), with P = .003 for sex interaction. The relative risk of hospitalization for worsening failure between reduced and preserved ejection fraction was greater in men than women (HR 5.97, 95% CI 1.40-25.56, P = .001 in men vs HR 2.65, 95% CI 0.68-10.31, P = .159 in women).
Conclusion: A survival advantage for women was seen in heart failure with reduced or preserved ejection fraction. In contrast, women appeared to be at lower risk for hospitalization for heart failure only when left ventricular systolic dysfunction was present.