P-1041. Contemporary Increase in Candidemia Mortality Is Associated with Antifungal Resistance and Patient Demographics

Abstract Background Candida spp. commonly cause bloodstream infections (BSI) in chronically ill patients, and Candida BSI is increasingly due to antifungal-resistant species. This retrospective cohort study examined temporal trends in candidemia epidemiology and associations between epidemiologic changes and mortality.Table 1.Characteristics of patients with different bloodstream infection types. Methods We included patients in a large healthcare system with a first BSI due to Escherichia coli or Klebsiella pneumonia (gram-negative bacteremia [GNB]), Staphylococcus aureus (SAB), or Candida spp. (candidemia) from 6/2016-6/2023. We compared 30-day mortality and demographics between BSI types. We examined changes in candidemia demographics, mortality, and causative species, both by individual year and by period (period 1, 2016-2019 vs. period 2, 2020-2023).Figure 1.Changes in mortality due to bloodstream infection types examined. Results Of 12057 patients, 7801 (64.7%) had GNB, 3602 (29.9%) SAB, and 654 (5.4%) candidemia (baseline characteristics in Table 1). Thirty-day mortality was highest for candidemia (30.9% vs. 13.4% for SAB and 8.0% for GNB, p< .01 by χ2). There was a trend toward increased mortality for patients with candidemia (p=0.06 by Mann-Kendall test, Figure 1). Candidemia mortality was significantly higher in period 2 vs. 1 (36.8% vs. 22.7%, p< .01 by χ2). Candidemia patients in period 2 tended to be older (mean age 66.3±14.3 vs. 63.8±16.2, p=0.04 by t-test); age was associated with mortality among patients with candidemia (OR 1.02, 95% CI 1.01-1.04 per year increase). Of species examined, only the incidence of C. auris increased (p< 0.01 by Mann-Kendall test, Figure 2). C. glabrata was associated with the highest 30-day mortality (36.3%) among common species; C. auris mortality was 17.4%. While the proportion of candidemia cases due to antifungal-resistant species (C. auris, glabrata, krusei, lusitaniae, parapsilosis) did not change between periods (p=0.79), mortality from these species was significantly higher in period 2 vs. 1 (36.1% vs. 21.5%, p< 0.01).Figure 2.Increasing prevalence of candidemia due to C. auris, 2016-2023. Conclusion Candidemia mortality increased significantly starting in 2020, at least in part due to increasing patient age and increased mortality associated with antifungal-resistant candidemia. Urgent efforts are needed to combat candidemia in an ageing population prone to antifungal-resistant Candida infections. Disclosures All Authors: No reported disclosures