Mortality Rate Among Women Hospitalized With a Primary Diagnosis of Urinary Tract Infection: Analysis From a National Database 2016 to 2020

INTRODUCTION: Despite its significant prevalence, there is a lack of data evaluating mortality and serious morbidity among women hospitalized for UTI. The aim of this study was to evaluate the risk factors for mortality following hospitalization for UTI. OBJECTIVE: Evaluate the incidence of and risk factors associated with mortality among women hospitalized for urinary tract infections (UTIs). METHODS: This was a retrospective cohort study using the National Inpatient Sample of adult women hospitalized with a UTI between 2016 and 2020. Patients were identified using International Classification of Disease (ICD-10) codes. Demographic, hospital level data, comorbidities, and associated diagnoses and procedures were collected. The primary outcome was death during hospitalization. Independent predictors of death were analyzed using multivariable logistic regression. For model selection, we applied backward stepwise selection of variables that occurred in 2% or more of hospitalizations (irrespective of outcome). Descriptive statistics were performed using t-test, chi-squared test, and univariable logistic regression. RESULTS: There were a total of 371,035 hospitalizations with a primary diagnosis of UTI, with 0.45% (n=1,663) deaths. Death occurred most commonly in those >85 years, 0.91%, and least in those younger than 50 years, 0.05%. In rural hospital locations, death occurred more frequently (18% vs 13%, p<0.001). A diagnosis of cystitis occurred more frequently among those that died (15.8% vs 12.7%, p<0.001). More complicated UTI diagnoses, such as pyelonephritis (3.2% vs 9.7%), occurred less frequently in those that died (p<0.001). Median length of stay was longer among deaths [5.0 days (IQR 2.0, 10.0) vs 3.0 days (IQR 2.0, 4.0) p<0.001]. In multivariable analysis, death during admission was most strongly correlated with increasing age: >85 years [aOR 8.87 (95% CI 6.21–12.67)], age 76–85 [aOR 5.96 (95% CI 4.18–8.52)], age 66–75 [aOR 4.67 (95% CI 3.26–6.70)], age 51–65 [aOR 3.39 (95% CI 2.34–4.91)] compared to those 18–50 years. The comorbidities associated with death included: metastatic cancer [aOR 4.49 (95% CI 3.75–5.38)], pneumonia [aOR 3.49 (95% CI 2.97–4.11)], and weight loss [aOR 2.98 (95% CI 2.66–3.34)]. Bacteremia [aOR 0.62 (95% CI 0.42–0.90)], hypertension [aOR 0.69 (95% CI 0.60–0.78)], depression [aOR 0.74 (95% CI 0.65–0.86)], and obesity [aOR 0.80 (95% CI 0.67–0.96)] were independently associated with a decreased probability of death. CONCLUSIONS: Death during hospitalization for a diagnosis of UTI is rare, even in critically ill and extreme elderly patients. However, certain comorbidities including metastatic cancer, pneumonia, and weight loss were associated with mortality.