A ‘substantial proportion’ of antibiotic prescriptions for most common infections treated in primary care have durations exceeding those recommended in guidelines, a new analysis of English primary care data has shown. The authors of the study*, published today in the BMJ, called for a better understanding of why clinicians tend to prescribe antibiotic courses that are longer than guideline recommendations, especially for respiratory tract infections – and said we could achieve considerable reductions in antibiotic exposure by aligning antibiotic prescription durations with the guidelines. An accompanying editorial called for future campaigns to convince doctors and patients to abandon longer courses of antibiotics as well as to emphasise that, when antibiotics are needed, shorter courses are sufficient to kill bacteria and less harmful than longer courses.
Researchers from Public Health England, the Universities of Groningen (Netherlands) and Oxford, and elsewhere pointed out that evidence about the contribution of excessive treatment duration to antibiotic overuse in primary care is limited, so they conducted a cross-sectional study to evaluate the duration of prescriptions for antibiotic treatment for common infections in English primary care and to compare this with guideline recommendations.
They analysed general practice data from The Health Improvement Network database (THIN), for 2013-15, covering 931,015 consultations that resulted in an antibiotic prescription for one of several indications: acute sinusitis, acute sore throat, acute cough and bronchitis, pneumonia, acute exacerbation of chronic obstructive pulmonary disease (COPD), acute otitis media, acute cystitis, acute prostatitis, pyelonephritis, cellulitis, impetigo, scarlet fever, and gastroenteritis. The main outcomes that they considered were the proportion of antibiotic prescriptions with a duration exceeding the guideline recommendation, and the total number of days beyond the recommended duration for each indication. Overall, the most common recorded reasons for prescription of antibiotics were acute cough and bronchitis (41.6% of the included consultations), acute sore throat (25.7%), acute otitis media (8.9%), and acute sinusitis (8.2%).
They found that antibiotic treatments for upper respiratory tract indications and acute cough and bronchitis accounted for more than two-thirds of the total prescriptions that they considered, and 80% or more of these treatment courses exceeded guideline recommendations. In comparison, for acute sinusitis only 9.6% of prescriptions exceeded seven days and for acute sore throat only 2.1% exceeded 10 days (recent guidance recommends five days); yet more than half (54.6%) of the antibiotic prescriptions were for longer than guidelines recommend for acute cystitis among females. They noted that the percentage of antibiotic prescriptions exceeding the recommended duration was lower for most non-respiratory infections.
The study authors also calculated that for all 931,015 included consultations resulting in antibiotic prescriptions, about 1.3 million days were beyond the durations recommended by guidelines. They said their study had shown that that unnecessary exposure to antibiotics may be substantially reduced by aligning the course length more with guidelines and best available evidence, not just by avoiding prescription of antibiotics when unnecessary. They called for better understanding of why clinicians tend to prescribe longer than recommended courses, especially for respiratory infections.
They concluded: “For most common infections treated in primary care, a substantial proportion of antibiotic prescriptions have durations exceeding those recommended in guidelines. Substantial reductions in antibiotic exposure can be accomplished by aligning antibiotic prescription durations with guidelines.”
In his accompanying editorial**, Alastair Hay from the University of Bristol argued: “Prescribers cannot be held responsible for what they were doing before new guidelines were issued, but we can familiarise ourselves with new guidance from the National Institute for Health and Care Excellence on managing common infections and optimise practice from here on. Both clinicians and patients may need convincing to abandon longer courses of antibiotics, and future campaigns by Public Health England to ‘Keep Antibiotics Working’ could usefully emphasise that when antibiotics are needed, shorter courses are sufficient to kill bacteria and less harmful than longer courses. Also, that some symptoms should be expected to persist beyond the end of the course, in some cases for up to four weeks.”
*Pouwels KB, Hopkins S, Llewelyn MJ, et al. Duration of antibiotic treatment for common infections in English primary care: cross sectional analysis and comparison with guidelines. BMJ 2019; 364: l440 http://dx.doi.org/10.1136/bmj.l440.
**Hay A. Antibiotic prescribing in primary care. BMJ 2019; 364: l780 doi: 10.1136/bmj.l78.