Antibiotic prescribing patterns in out-of-hours primary care: a population-based descriptive study

Objective: To describe the frequency and characteristics of antibiotic prescribing for different types of contacts with the Danish out-of-hours (OOH) primary care service.

Design: Population-based observational registry study using routine registry data from the OOH registration system on patient contacts and ATC-coded prescriptions.

Setting: The OOH primary care service in the Central Denmark Region.

Subjects: All contacts with OOH primary care during a 12-month period (June 2010-May 2011).

Main outcome measures: Descriptive analyses of antibiotic prescription proportions stratified for type of antibiotic, patient age and gender, contact type, and weekdays or weekend.

Results: Of the 644 777 contacts registered during the study period, 15.0% received an antibiotic prescription: 26.1% resulted from clinic consultations, 10.7% from telephone consultations, and 10.9% from home visits. The prescription proportion was higher for weekends (17.6%) than for weekdays (10.6%). The most frequently prescribed antibiotic drugs were beta-lactamase sensitive penicillins (34.9%), antibiotic eye drops (21.2%), and broad-spectrum penicillins (21.0%). Most antibiotic eye drops (73%) were prescribed in a telephone consultation. Most antibiotics were prescribed at 4-6 p.m. on weekdays. Young infants received most antibacterial eye drops (41.3%), patients aged 5-17 years and 18-60 years received most beta-lactamase sensitive penicillins (44.6% and 38.9%, respectively), while patients aged 60 + years received most broad-spectrum penicillins (32.9% of all antibiotic prescriptions).

Conclusion: Antibiotics were most often prescribed in clinic consultations, but, in absolute terms, many were also prescribed by telephone. The high prescription proportion, particularly antibacterial eye drops for young infants, suggests room for improvement in rational antibiotic use.