Antibiotic prescribing for care-home residents: a population-based, cross-classified multilevel analysis in Scotland, UK

• Published in: Age and ageing Vol. 54; no. 1
• Main Authors: De Souza, Nicosha, Guthrie, Bruce, Grant, Suzanne, Lorencatto, Fabiana, Dickson, Jane, Herbec, Aleksandra, Hughes, Carmel, Sneddon, Jacqueline, Donnan, Peter T, Marwick, Charis A
• Format: Journal Article
• Language: English
• Published: England Oxford Publishing Limited (England) 06.01.2025; Oxford University Press
• Subjects: Age Factors; Aged; Aged, 80 and over; Anti-Bacterial Agents - therapeutic use; Antibiotics; Antimicrobial resistance; Antimicrobial Stewardship; Comorbidity; Drug Prescriptions - statistics & numerical data; Drug resistance; Female; General practice; Homes for the Aged - statistics & numerical data; Humans; Male; Management; Multilevel Analysis; Multivariate analysis; Nursing Homes - statistics & numerical data; Older people; Practice Patterns, Physicians' - statistics & numerical data; Prescribing; Prescription drugs; Research Paper; Sampling; Scotland - epidemiology; Unexplained; Variation; Scotland; antibiotic; older people; antimicrobial stewardship; antibiotic prescribing; cross-classified; care-homes
• ISSN: 0002-0729; 1468-2834; 1468-2834
• DOI: 10.1093/ageing/afae288

There is wide variation in antibiotic prescribing across care-homes for older people, with implications for resident outcomes and antimicrobial resistance. To quantify variation in antibiotic prescribing and associations with resident, care-home and general practice characteristics. Population-based analyses using administrative data. 148 care-homes in two Scottish regions, with 6633 residents registered with 139 general practices. Prescriptions for any antibiotic and for broad-spectrum antibiotics between 1 April 2016 and 31 March 2017 were analysed using cross-classified multilevel negative binomial regression. For any antibiotics, the mean prescription rate was 6.61 (SD 3.06) per 1000 resident bed-days (RBD). In multivariate analysis, prescribing was associated with resident age [incidence rate ratio (IRR) 1.30 [95% confidence interval 1.19 to 1.41] for 90+ versus <80 years old] and comorbidity (1.88 [1.71 to 2.06] for Charlson Comorbidity Index 3+ versus 0), and the care-home's sampling rate for microbiological culture (1.53 [1.28 to 1.84] for >7 versus <3.5 samples per 1000 RBD), with residual unexplained variation between care-homes (median IRR 1.29 [1.23 to 1.36]) and general practices (1.11 [1.05 to 1.18]). For broad-spectrum antibiotics, the mean rate was 0.98 (0.92) per 1000 RBD. Broad-spectrum prescribing was also associated with resident age, sex, comorbidity and sampling rate, with larger residual unexplained variation between care-homes (1.56 [1.36 to 1.77]) and general practices (1.51 [1.31 to 1.72]). Variation in prescribing was influenced by resident case-mix, but there is significant unexplained variation between care-homes and between general practices, indicating a need for antibiotic stewardship to target both.