Antibiotic Exposure and Risk of MDR Urinary Tract Infections: A Case-Control Study
Abstract
Background: Antimicrobial resistance (AMR) is a critical global health threat. Antibiotic consumption is a key modifiable risk factor for multidrug-resistant (MDR) infections, yet its magnitude across healthcare settings remains poorly characterised.
Objectives: To estimate the association between antibiotic consumption and MDR urinary tract infection (UTI) development, assess the impact of increasing antibiotic diversity, and characterise resistance patterns across healthcare settings.
Methods: Observational case-control study using laboratory and clinical data from a tertiary care hospital (2023). Cases were urine samples with MDR isolates; controls had susceptible isolates. Exposure was defined as systemic antibiotic use within the prior 12 months. Odds ratios (OR) and binary logistic regression were used to estimate crude and adjusted associations.
Results: We included 351 cases and 790 controls (median age 75; 74% female). Prior antibiotic use was associated with MDR UTI development (adjusted OR 2.30; 95% CI 1.63–3.23). Increasing antibiotic diversity (number of antibiotic classes used) was independently associated with MDR UTIs, with a 40% risk increase per additional class (OR 1.40; 95% CI 1.29–1.51). Associations between consumption of twelve antibiotic classes and MDR UTI development were identified, and six remained significant in multivariate analysis: carbapenems, third-generation cephalosporins, lipopeptides, oxazolidinones, β‑lactam/β‑lactamase inhibitor, and sulfonamides. Resistance patterns differed significantly between community and hospital-acquired infections (p < 0.001), with ESBL-producing E. coli predominating in both community (67.6%) and hospital settings (26.9%).
Conclusions: Exposure to carbapenems, third‑generation cephalosporins, and β‑lactam/β‑lactamase inhibitor combinations most strongly increased MDR UTI risk. Cumulative effects and distinct resistance patterns support targeted restrictions and setting‑specific stewardship policies.
Key messages: • Our study reveals that increasing antibiotic diversity significantly drives MDR UTI risk. We advocate for targeted stewardship to limit high-impact antibiotic combinations.
• Resistance patterns vary sharply between community and hospital settings. Our findings highlight the need for setting-specific policies to curb the rise of carbapenem-resistant infections.
Related
- Antibiotic treatment of male urinary tract infections: scientific rationale behind the 2026 SPILF guidelines
- Antibiotic prescribing appropriateness for urinary tract infections in a tertiary emergency department: a retrospective cohort study.
- AFSSAPS recommendations for the management of urinary tract infections in children
- Development of iPSC-derived urothelial organoids towards investigating the effect of hormones on host-defense to urinary tract infections
- Large-scale metagenomic characterization of the vaginal microbiome and uropathogens in women with recent bacterial vaginosis and urinary tract infections
BibTeX
@article{costa2026antibiotic,
title = {{Antibiotic Exposure and Risk of MDR Urinary Tract Infections: A Case-Control Study}},
author = {M Mateus da Costa and P Moreno Nuñez and J Vicente-Guijarro and G Quinaz Romana and P Ruiz-Garbajosa and M Ponce-Alonso and R Cantón and JM Aranaz and P Sousa},
journal = {The European Journal of Public Health},
year = {2026},
month = oct,
doi = {10.1093/eurpub/ckag169.633},
url = {https://doi.org/10.1093/eurpub/ckag169.633},
note = {CC BY-NC 4.0},
}
RIS
TY - JOUR
TI - Antibiotic Exposure and Risk of MDR Urinary Tract Infections: A Case-Control Study
AU - M Mateus da Costa
AU - P Moreno Nuñez
AU - J Vicente-Guijarro
AU - G Quinaz Romana
AU - P Ruiz-Garbajosa
AU - M Ponce-Alonso
AU - R Cantón
AU - JM Aranaz
AU - P Sousa
PY - 2026
DA - 2026/10/01
JO - The European Journal of Public Health
DO - 10.1093/eurpub/ckag169.633
UR - https://doi.org/10.1093/eurpub/ckag169.633
AB - Background: Antimicrobial resistance (AMR) is a critical global health threat. Antibiotic consumption is a key modifiable risk factor for multidrug-resistant (MDR) infections, yet its magnitude across healthcare settings remains poorly characterised. Objectives: To estimate the association between antibiotic consumption and MDR urinary tract infection (UTI) development, assess the impact of increasing antibiotic diversity, and characterise resistance patterns across healthcare settings. Methods: Observational case-control study using laboratory and clinical data from a tertiary care hospital (2023). Cases were urine samples with MDR isolates; controls had susceptible isolates. Exposure was defined as systemic antibiotic use within the prior 12 months. Odds ratios (OR) and binary logistic regression were used to estimate crude and adjusted associations. Results: We included 351 cases and 790 controls (median age 75; 74% female). Prior antibiotic use was associated with MDR UTI development (adjusted OR 2.30; 95% CI 1.63–3.23). Increasing antibiotic diversity (number of antibiotic classes used) was independently associated with MDR UTIs, with a 40% risk increase per additional class (OR 1.40; 95% CI 1.29–1.51). Associations between consumption of twelve antibiotic classes and MDR UTI development were identified, and six remained significant in multivariate analysis: carbapenems, third-generation cephalosporins, lipopeptides, oxazolidinones, β‑lactam/β‑lactamase inhibitor, and sulfonamides. Resistance patterns differed significantly between community and hospital-acquired infections (p < 0.001), with ESBL-producing E. coli predominating in both community (67.6%) and hospital settings (26.9%). Conclusions: Exposure to carbapenems, third‑generation cephalosporins, and β‑lactam/β‑lactamase inhibitor combinations most strongly increased MDR UTI risk. Cumulative effects and distinct resistance patterns support targeted restrictions and setting‑specific stewardship policies. Key messages: • Our study reveals that increasing antibiotic diversity significantly drives MDR UTI risk. We advocate for targeted stewardship to limit high-impact antibiotic combinations. • Resistance patterns vary sharply between community and hospital settings. Our findings highlight the need for setting-specific policies to curb the rise of carbapenem-resistant infections.
SN - 1101-1262
SN - 1464-360X
ER -