title: Risk factors for resistance to antimicrobial agents among nursing home residents.
abstract: The authors prospectively collected data on exposure to antimicrobial agents and susceptibility patterns among all clinical isolates of bacteria taken from 9,156 residents of 50 nursing homes in Canada and the United States in 1998-1999. Exposure to antimicrobial agents was measured during the 10 weeks prior to detection of targeted resistant bacteria in residents and compared with antibiotic exposure during a 10-week interval in individuals with sensitive organisms. These main effects were adjusted for infection-control and staffing covariates using multiple logistic regression modeling. Increased staffing of nursing homes with registered nurses (adjusted odds ratio (OR) = 0.79 (95% confidence interval (CI): 0.72, 0.87) per registered nurse per 100 resident-days) and use of antibacterial soap (adjusted OR = 0.40, 95% CI: 0.18, 0.90) were associated with reduced risk of methicillin-resistant Staphylococcus aureus in nursing home residents. An increase in the number of hand-washing sinks per 100 residents was shown to reduce the risk of trimethoprim-sulfamethoxazole (TMP/SMX)-resistant Enterobacteriaceae (adjusted OR = 0.94, 95% CI: 0.90, 0.98). Exposure to TMP-SMX and exposure to fluoroquinolones were significant risk factors for isolation of TMP-SMX-resistant Enterobacteriaciae (adjusted OR = 1.14, 95% CI: 1.06, 1.22) and fluoroquinolone-resistant Enterobacteriaciae (adjusted OR = 1.08, 95% CI: 1.04, 1.11), respectively. These findings suggest that increased staffing, more hand-washing sinks, and use of antimicrobial soap may reduce resistance to antimicrobial agents in long-term care facilities.
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University and Hamilton Regional Laboratory Program, Hamilton, Ontario, Canada. loebm@mcmaster.ca
authors.forename: Mark B
authors.initials: MB
authors.lastname: Loeb
authors.forename: Sharon
authors.initials: S
authors.lastname: Craven
authors.forename: Allison J
authors.initials: AJ
authors.lastname: McGeer
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Simor
authors.forename: Suzanne F
authors.initials: SF
authors.lastname: Bradley
authors.forename: Donald E
authors.initials: DE
authors.lastname: Low
authors.forename: Maxine
authors.initials: M
authors.lastname: Armstrong-Evans
authors.forename: Lorraine A
authors.initials: LA
authors.lastname: Moss
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Walter
mesh_terms: D000900:Anti-Bacterial Agents; D001424:Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000517:prevention & control; D002170:Canada / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology* / Q000517:prevention & control; D004351:Drug Resistance; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis; D006235:Hand Disinfection / Q000379:methods / Q000592:standards; D006801:Humans; D017053:Infection Control / Q000379:methods / Q000592:standards; D016015:Logistic Models; D008826:Microbial Sensitivity Tests; D015999:Multivariate Analysis; D009735:Nursing Homes / Q000458:organization & administration; D010561:Personnel Staffing and Scheduling / Q000706:statistics & numerical data; D011446:Prospective Studies; D012307:Risk Factors; D012915:Soaps; D014481:United States / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D012915:Soaps