Relationships between sex, early valve surgery and mortality in patients with left-sided infective endocarditis analysed in a population-based cohort study.

OBJECTIVE: Whether sex-related differences in the prognosis of infective endocarditis (IE) are due to differences in disease severity or comorbid patterns, physiological specificities or a treatment indication bias is unclear. We conducted an analysis of the pooled database of two population-based cohorts of IE to reassess the relationships between sex, early valve surgery (EVS) and outcome in patients with IE.

METHODS: Demographic and baseline characteristics, complications and outcome were compared in men and women with Duke-definite left-sided IE. A propensity model for EVS was constructed using multivariate logistic regression. Factors associated with 1-year mortality were identified using multivariate Cox models adjusted for EVS factors.

RESULTS: The study population included 466 (75%) men and 154 (25%) women. Compared with men, women were older (p=0.005), were more often on haemodialysis (p=0.04), more often had a mitral valve IE (50.0% vs 35.8%, p=0.02), less often developed a septic shock (p=0.05), less often underwent EVS (p=0.001) yet had comparable inhospital mortality rates (20.1% vs 20.0%, p=0.96) and similar 1-year survival probability (logrank p=0.68). Female sex was neither associated with EVS (OR 0.76 (95% CI 0.49 to 1.16)) nor mortality (HR 1.17 (95% CI 0.80 to 1.69)). However EVS was associated with an increased risk of death in women in the early postoperative period (HR 8.72 (95% CI 3.42 to 22.24), p=<0.0001).

CONCLUSIONS: Women underwent EVS less often than men. However female sex was independently associated with neither EVS nor 1-year mortality. The reasons for a higher risk of early postoperative mortality in women must still be elucidated.