Risk factors for urinary tract infections in geriatric hospitals.

Background: Urinary tract infection (UTI) is the most frequent nosocomial infection in geriatric units. An understanding of risk factors for infection may help to identify prevention strategies.

Aim: Identification of the risk factors for UTI in elderly patients.

Methods: Retrospective analysis of three prospective cohorts. All hospitalized patients present in, or admitted to, a geriatric unit from June 1st to June 28th, for the years 2009, 2012, and 2015 were included and followed until discharge or until June 30th of the year concerned. For each patient, type and dates of stay, type and dates of catheter, risk factors, and nosocomial UTI (NUTI) data were collected. Univariate and multivariate (Cox model) analyses were made using SPSS software.

Findings: A total of 4669 patients were included and were followed for a total of 83,068 days. There were 189 NUTIs (4.0% patients). NUTIs were significantly more frequent among female patients, in rehabilitation units, in immunosuppressed patients, among those with acute retention, post-void residual, history of urinary tract infection in the previous six months, and in case of dependency. NUTIs were significantly more frequent among those who had a catheter (Z-test, P < 0.001). NUTIs were more frequent among patients with intermittent, indwelling, or suprapubic catheters. They were also more frequent in acute/subacute care or rehabilitation units, in women, in immunosuppressed patients, and in those with a history of previous UTI; they were less frequent in dementia patients.

Conclusion: The occurrence of NUTI is an important issue in both catheterized and non-catheterized patients; prevention programmes should be widened to include non-catheterized patients.