Sex-based differences and clinical outcomes in older adults with Candida bloodstream infection: a post-hoc secondary analysis of a multicentre study.

Abstract

Candida bloodstream infections (BSI) are a major cause of disease in hospitalized patients, with particularly high morbidity and mortality among older adults. However, the impact of biological sex on clinical presentation and outcomes in this population remains poorly defined. We evaluated sex-based differences in patients aged ≥65 years with Candida BSI. We conducted a retrospective multicenter cohort study across three hospitals in Italy and Spain (2018-2022), including all patients aged ≥65 years with Candida BSI. The primary outcome was 30-day all-cause mortality. Cox regression and 1:1 propensity score matching were used to assess the association between biological sex and mortality and to identify independent predictors of outcome. A total of 1132 patients were included (53.4% male; median age 79 years). Men had a higher comorbidity burden and more severe clinical presentation at onset. Overall, 30-day mortality was 46.9%, with no significant difference between sexes (log-rank p = .929). In multivariable analysis, older age, higher Charlson Comorbidity Index, and septic shock were independently associated with mortality, whereas biological sex was not (aHR 1.19, 95% CI 0.95-1.50, p = .136). After propensity score matching, biological sex was not associated with mortality, while adequate source control was protective (aHR 0.62, 95% CI 0.47-0.82, p = .0008). In older adults with Candida BSI, short-term mortality is driven primarily by disease severity, comorbidity burden, and adequacy of management rather than biological sex. Optimizing timely antifungal therapy and source control appears critical to improving outcomes in this vulnerable population.