Length of Stay and Mortality Associated with Healthcare-Associated Urinary Tract Infections: A Multistate Model

Abstract

Background: To evaluate the current incidence, mortality and length of stay associated with healthcare associated urinary tract infections (HAUTIs). Material/methods: A non-concurrent cohort study design is used, conducted between 1 January 2010 and 30 June 2014. All patients admitted to one of the eight participating Australian hospitals and who were hospitalised more than two days were included. The primary outcomes measures were the incidence, mortality and excess length of stay associated with healthcare associated urinary tract infections. Results: From 162,503 patient admissions, 1.73% (95% CI 1.67–1.80) of admitted patients acquired a HAUTI. Using a multi-state model, the expected extra length of stay due to HAUTI was 4 days, 95% CI 3.1–5.0 days. Using a Cox regression model, infection significantly reduced the rate of discharge (HR 0.78, 95%CI, 0.73-0.83. Women were less likely to die (HR 0.71, 95%CI 0.66-0.75), whereas older patients were more likely to die (HR 1.40, 95%CI 1.38-1.43). Death was rarer in a tertiary referral hospital compared to other hospitals, after adjusting for age and sex (HR 0.74, 95%CI, 0.69-0.78). Conclusions: This study is the first study to explore the burden of HAUTIs in hospitals using appropriate statistical methods in a developed country. Our study indicates that the incidence of HAUTI in addition to its associated extra length of stay in hospital, present a burden to the hospital system. With increasing incidence of UTI due to antimicrobial resistant organisms, surveillance and interventions to reduce the incidence of HAUTI are required.