Advanced age is not a risk factor for mortality in patients with bacteremia caused by extended-spectrum β-lactamase-producing organisms: A multicenter cohort study

Abstract

A 5-year multicenter retrospective cohort study was conducted across six hospitals in Niigata, Japan. Patients (n = 179) with bacteremia due to extended-spectrum β-lactamase (ESBL)-producing organisms were included in the study. The rates of appropriate carbapenem prescription were 61% (n = 41) in patients aged 65–84 years and 89% (n = 31) in those aged ≥ 85 years. Patients aged ≥ 85 years were significantly more likely to receive carbapenem than their younger counterparts. After propensity score matching, 65 patients were assigned to two groups based on age (65–84 years or ≥ 85 years). Multivariate regression analysis showed that other sites of infection had a positive association with 30-day mortality (odds ratio [OR], 27.50; 95% confidence interval [CI], 2.90–260.00) and biliary tract infection tended to have a positive association with 30-day mortality (OR, 8.90; 95% CI, 0.88– 89.90) compared with urinary tract infection. However, an age ≥ 85 years was not associated with 30-day mortality. Elderly patients aged ≥ 85 years were more likely to be treated with carbapenem; however, old age was not associated with 30-day mortality when bacteremia was caused by ESBL-producing organisms. These results may help clinicians justify withholding carbapenem in patients aged ≥ 85 years.