Association between the number of antibiotic types used and in-hospital mortality in patients with chronic kidney disease stage 5: A propensity score-matched study

This study aimed to investigate the association between antibiotic use and in-hospital mortality among patients with chronic kidney disease stage 5 (CKD5), to inform optimized antibiotic stewardship. A retrospective study was conducted on patients diagnosed with CKD5 in the nephrology department of a tertiary hospital in Guangxi, China, from January 2022 to December 2024. Patients with in-hospital mortality were matched with surviving controls using propensity score matching. Firth penalized logistic regression was employed to reduce small-sample bias, and E-values were calculated to assess robustness to unmeasured confounding. Indicators of antibiotic use were then analyzed and compared between the 2 groups. A total of 3359 CKD5 patients were enrolled, with an in-hospital mortality rate of 0.98%. After propensity score matching (31 in-hospital mortality matched with 62 survivors), multivariable analysis showed that the number of antibiotic types used was significantly associated with in-hospital mortality (Firth odds ratio = 1.650, 95% CI: 1.148-2.492, P = .006; E-value = 1.889). This association was further supported by categorical analysis, where most antibiotic type categories showed significantly elevated mortality odds compared with no antibiotic use. Duration of antibiotic use (DOAU) was also significantly associated with mortality, though the effect size was modest (odds ratio = 1.081, 95% CI: 1.003-1.173, P = .041). Multivariate regression analysis further clarified the factors influencing antibiotic use indicators: types of antibiotics used was significantly associated with number of pathogenic species, total duration of fever, and number of venous catheterizations. Separately, DOAU was associated with total duration of fever, ICU days, and number of pathogenic species . The number of antibiotic types used is independently associated with in-hospital mortality in patients with CKD5, with DOAU showing a modest but significant association. These results support more cautious antibiotic stewardship in patients with CKD5, including improving etiological testing before antibiotic administration and avoiding unnecessary increases in the number of antibiotic types used. Nevertheless, these findings warrant validation in larger prospective cohorts.