Sex differences in the diagnosis, management and outcomes of patients with infective endocarditis

Despite growing interest in male-female differences in cardiovascular disease, evidence in infective endocarditis (IE) is limited and contradictory.

This prospective study included all patients with definite or possible valvular IE discussed by the endocarditis team from 2016 to 2025. Baseline characteristics, diagnostics, treatment and outcomes were compared between sexes. A Cox model was conducted to assess survival adjusted for baseline characteristics, IE type and treatment.

The cohort included 791 patients with definite or possible IE (72.8% males, 27.2% females). Age was not different (male: 67 (IQR 56-75), female: 71 (IQR 55-78) years, p=0.07). Females more often had hypertension (46.0% vs 35.2%, p=0.07) and mitral valve IE (45.6% vs 32.3%, p<0.001). Males had more predisposing conditions (71.5% vs 60.5%, p=0.004) and more aortic valve IE (71.0% vs 62.3%, p=0.02) and Cutibacterium species (5.7% vs 1.4%, p=0.007). There was no difference in indication for surgery. However, males were more often treated surgically (41.1% vs 29.3%, p=0.002), and females with an indication for surgery were more often treated conservatively (22.5% vs 37.0%, p=0.006). After a median follow-up of 2.1 (IQR 0.4-4.4) years, females had higher mortality (adjusted HR (aHR) 1.39 (95% CI 1.03 to 1.89), p=0.03). Surgery was associated with higher mortality in males (aHR 1.32 (95% CI 0.90 to 1.94) vs aHR 0.62 (95% CI 0.32 to 1.20), p value for interaction=0.03).

Differences were observed in baseline characteristics, IE type and survival. Females had worse overall adjusted survival, suggesting a less favourable overall prognosis. In terms of surgical decision-making, surgery was withheld more often in females despite surgical indication, and after excluding these patients, surgery appeared more protective in females than in males. These findings may reflect sex differences in surgical selection.