Sociodemographic Inequalities in Urinary Tract Infection in 2 Large California Health Systems

Background Urinary tract infection (UTI) accounts for a substantial portion of outpatient visits and antibiotic prescriptions in the United States. Few studies have considered sociodemographic factors including low socioeconomic status (SES)—which may increase residential crowding, inappropriate antibiotic prescribing, or comorbidities—as UTI or multidrug-resistant (MDR) UTI risk factors. Methods We used 2015–2017 electronic health record data from 2 California health care systems to assess whether 3 sociodemographic factors—use of Medicaid, use of an interpreter, and census tract–level deprivation—were associated with overall UTI or MDR UTI. UTIs resistant to ≥3 antibiotic classes were considered MDR. Results Analyses included 601 352 UTI cases, 1 303 455 controls, and 424 977 urinary Escherichia coli isolates from Kaiser Permanente Southern California (KPSC) and Sutter Health in Northern California. The MDR prevalence was 10.4% at KPSC and 12.8% at Sutter Health. All 3 sociodemographic factors (ie, use of Medicaid, using an interpreter, and community deprivation) were associated increased risk of MDR UTI. For example, using an interpreter was associated with a 36% (relative risk [RR], 1.36; 95% CI, 1.31 to 1.40) and 28% (RR, 1.28; 95% CI, 1.22 to 1.34) increased risk of MDR UTI at KPSC and Sutter Health, respectively, adjusted for SES and other potential confounding variables. The 3 sociodemographic factors were only weakly associated with UTI overall. Conclusions We found low SES and use of an interpreter to be novel risk factors for MDR UTI in the United States.