Impact of sex on clinical management and mortality in community-onset Staphylococcus aureus bacteraemia: a retrospective study

Staphylococcus aureus bacteraemia is a severe infection with potential sex-based disparities. While males have higher infection rates, females may experience poorer clinical outcomes. This study examines sex-based differences in the clinical characteristics, management approaches, and outcomes of community-onset S. aureus bacteraemia (COSAB) within a single-centre cohort. We conducted a single-centre retrospective study of 279 COSAB cases (2015–2020) at University Hospital Geelong, Australia. Clinical characteristics, diagnostic testing, and 30-day all-cause mortality were compared by sex using univariable binomial logistic regression models. Analysis of 279 COSAB cases (58.4% males, 41.6% females) showed a higher, though not statistically significant association between 30-day mortality rate in females (21.6%) compared to males (17.2%) (p = 0.36). There was no significant difference of age between the sexes (p = 0.38) or Charlson Age Comorbidity Index (p = 0.71). Males had longer median hospital stay (26 days, IQR: 33.25 compared to females (18 days, IQR: 34). Transoesophageal echocardiography (TOE) was performed less frequently in females than males (OR: 0.58, 95% CI 0.35–0.97; p = 0.04), despite comparable rates of infective endocarditis. Females were also associated with a methicillin-susceptible Staphylococcus aureus (MSSA) infection (OR: 2.10, 95% CI: 1.13–3.97, p = 0.02). This study identified sex-based differences in the management of COSAB, particularly the lower frequency of TOE performed in females. While there was no significant difference in 30-day mortality between sexes in this underpowered study, these disparities warrant further investigation. Understanding the underlying causes of these differences could help improve clinical practices and ensure equitable management for all patients.