Catheter-Associated Urinary Tract Infection (CAUTI) in the NeuroICU: Identification of Risk Factors and Time-to-CAUTI Using a Case-Control Design

Abstract

Background/objective: Catheter-associated urinary tract infections (CAUTIs) account for 25% of all hospital-acquired infections. Neuro-critically ill patients are at 2-5 times greater risk of developing CAUTI because of increased use of indwelling urinary catheters due to neurogenic urinary retention. Despite the heightened risk of CAUTI occurrence for the neuro-critically ill, there is little data on specific characteristics of CAUTIs and risk factors among this population. The aim of this study was to identify characteristics and risk factors associated with CAUTI development in the neuro-critical patient population.

Methods: In this retrospective single-center case-control study in a tertiary care dedicated 30-bed neuroICU, approximately 3 controls (exact ratio-3.2) were randomly selected for each CAUTI case between January 1st, 2016 and December 31st, 2018. Demographic, clinical and laboratory data were collected, including prospectively collected data pertaining to urinary and bowel function. Descriptive and multivariate logistic regression analysis was conducted to identify common patient characteristics, CAUTI risk factors and duration from catheterization to developing a CAUTI (Time-to-CAUTI).

Results: Of 3045 admissions during the study period, 1045 (34.30%) had a urinary catheter at some point during their admission. Of those, 45 developed a CAUTI, yielding a CAUTI incidence rate of 1.50%, corresponding to 4.49 infections/1000 catheter days. On average, CAUTI patients were older as compared to controls (66.44 years of age vs 58.09 years; p < 0.0001). In addition to old age, other risk factors included female gender (75.60% female vs 24.20% males in case group, p < 0.0001), increased neuroICU length of stay (18.31 in cases vs. 8.05 days in controls, p = 0.0001) and stool incontinence (OR = 3.73, p = 0.0146). CAUTI patients more often carried a primary diagnosis of SAH, and comorbidities of hypertension (HTN), vasospasm and diabetes. Time-to-CAUTI was 6 days on average, with an earlier peak for patients requiring two or more catheter placements. Presence of stool incontinence was significantly associated with CAUTI occurrence.

Conclusion: Stool incontinence, older age, female sex, longer neuroICU LOS and presence of comorbidities such as HTN and diabetes were associated with CAUTI development in the neuro-critically ill population. Average Time-to-CAUTI after catheter placement was 6 days with earlier occurrence if more frequent catheterizations. Colonization of urinary catheters without infection might contribute to CAUTI diagnosis. Prospective research is needed to determine impact of prevention protocols incorporating these factors.

Keywords: CAUTI; Catheter; NeuroICU; Urinary tract infection.