Variability in Hospital-Onset Bacteremia in Ontario

Importance Hospital-onset bacteremia and fungemia (HOB) is being proposed as a new hospital quality metric for health care–associated infections. There is a lack of data on the ability of HOB to discriminate between hospitals from a large regional perspective. Objective To describe and compare the HOB rates across hospitals for the province of Ontario in Canada. Design, Setting, and Participants This population-based retrospective cohort study used ICES Ontario databases. Participants were adult patients admitted to an acute care hospital from 2017 to 2024 in Ontario, Canada. Exposure Local care processes and practices in different hospitals. Main Outcomes and Measures HOB was defined as a positive blood culture collected on or after hospital day 4. HOB rates per admission-days were described across hospital sites. A generalized linear mixed-effects model was used to compare variation in HOB rates across hospitals while adjusting for patient and hospital characteristics. Results At 114 acute-care hospitals in Ontario, Canada, there were 3 325 900 hospital admissions (median [IQR] age, 71 [57-81] years; 1 727 228 female patients [51.9%]). In total, there were 61 452 HOB episodes observed over 29 721 745 admission-days, equal to an overall rate of 2.07 episodes per 1000 admission-days. Across the 114 acute-care hospitals, the HOB rates were 0.39 episodes per 1000 admission-days for the 10th percentile, 0.71 episodes per 1000 admission-days for the 25th percentile, 1.08 episodes per 1000 admission-days for the 50th percentile, 1.68 episodes per 1000 admission-days for the 75th percentile, and 2.27 episodes per 1000 admission-days for the 90th percentile. In a generalized linear mixed-effects model, the random intercept for hospital sites had an SD of 0.36 (95% CI, 0.29-0.42), which corresponded to a rate ratio of 1.43 (95% CI, 1.34-1.52) per 1 SD. Conclusions and Relevance In this cohort study of 114 hospitals, there was significant variability in hospital HOB rates, suggesting that HOB may be a useful quality metric in discriminating between hospitals.