In a U.S. multicenter retrospective cohort study reported in The Lancet Oncology, Gupta et al evaluated whether antimicrobial resistance was more common in pathogenic bacterial isolates from outpatients with cancer than in outpatients without cancer.
Study Details
The study involved data from the BD Insights Research Database on antimicrobial susceptibility of bacteria isolated from adults with or without cancer receiving care at 198 outpatient health-care settings in the United States. Patients without cancer were those who were not prescribed cancer medications and not admitted to an inpatient cancer unit in the predefined period; patients with cancer were those who received medication solely or sometimes indicated for cancer.
Key Findings
Data on 27,421 patients with cancer and 928,128 patients without cancer were collected between April 2018 and December 2022.
For Pseudomonas aeruginosa, carbapenem nonsusceptibility was identified in 14.4% (816 of 5,683) of pathogen isolates from patients with cancer vs 11.3% (10,709 of 94,419) of those from patients without cancer (odds ratio [OR] = 1.22, 95% confidence interval [CI] = 1.13–1.32).
For Enterobacterales, fluoroquinolone nonsusceptibility was higher in pathogen isolates from patients with cancer (28.0%, 8,662 of 30,867) vs patients without cancer (21.8%, 238,479 of 1,095,996; OR = 1.44, 95% CI = 1.40–1.47), as was carbapenem nonsusceptibility (1.5% vs 0.8%; OR = 1.89, 95% CI = 1.72–2.07); multidrug-resistant pathogens (8.7% vs 4.5%; OR = 2.03, 95% CI = 1.95–2.11); and extended-spectrum β-lactamase producers (16.5% vs 9.4%; OR = 1.96, 95% CI = 1.90–2.03).
For Staphylococcus aureus, methicillin resistance was higher in pathogen isolates from patients with cancer (53.0% [4,747 of 8,959] vs patients without cancer (48.3% [129,291 of 267,520]; OR = 1.20, 95% CI = 1.15–1.25). For Enterococcus spp, vancomycin resistance was higher in pathogen isolates from patients with cancer (18.6% [1,329 of 7,145]) vs patients without cancer (9.1% [12,333 of 135,772]; OR = 2.20, 95% CI = 2.06–2.34).
The antimicrobial resistance incidence rate ratio (IRR) per 1,000 isolates was higher in patients with cancer vs patients without cancer, particularly for carbapenem nonsusceptible P aeruginosa (IRR = 2.06, 95% CI = 1.91–2.21) and vancomycin-resistant enterococci (IRR = 3.06, 95% CI = 2.89–3.24).
The investigators concluded: “[Antimicrobial resistance] proportions and [incidence rate ratios] for most key pathogens were up to three times higher in isolates from outpatients with cancer than those without cancer, highlighting the need for enhanced surveillance, infection prevention, and timely diagnostic stewardship to improve antibiotic prescribing in this population.”
Diane C. Flayhart, MS, of the University of Tennessee Health Science Center, Memphis, is the corresponding author of The Lancet Oncology article.
Disclosure: The study was funded by the AMR Action Fund. For full disclosures of all study authors, visit The Lancet Oncology.
