Fall in GP antibiotic prescribing slowest for older patients

GPs in England are prescribing fewer antibiotics and when they do prescribe them they are increasingly choosing drugs that target a narrow range of organisms rather than broad-spectrum antibiotics, suggests new research from King’s College London School of Population Health & Environmental Sciences.

KCL prescriptionsThe research has been published online in BMJ Open.

However, falls in GPs’ rates of prescribing have been smaller in some groups of patients, in particular, patients aged over 55 and those with no clear diagnosis.

There has been a global drive to cut antibiotic use in response to the growing threat of antimicrobial resistance – a situation where bacteria develop resistance to antibiotics so become more difficult to treat and potentially ultimately untreatable.

Typically the more frequently antibiotics are used by a patient, the greater the number of bacteria that will be exposed to them and the more likely it is that those bacteria will subsequently become resistant.

Antibiotic stewardship policies promoting more considered use of antibiotics have been introduced to slow the development of antimicrobial resistance. These policies encourage GPs to reduce prescribing of antibiotics overall, and where they are needed to choose one effective against a narrow range of bacteria over broad-spectrum options, which target a wider range of bacteria.

Xiaohui Sun, PhD candidate in Population and Environmental Health Sciences, led the research which analysed GP prescription of antibiotics at 102 GP in England from 2014 to 2017 by extracting data from the UK Clinical Practice Research Datalink (CRPD).

The data showed that over that period, total antibiotic prescribing declined by 6.9% per year, while the rate of prescribing for broad-spectrum beta-lactam antibiotics, which target a wide range of organisms, fell more rapidly – by 9.3% per year.

Prescribing rates declined at a similar pace for male and female patients, but the rate of decline was lower for older patients (those aged over 55).

More than a third of antibiotics (38.8%) prescribed by GPs were associated with medical codes that did not indicate a clinical condition that would require their use, and a further 15.3% of antibiotic prescriptions had no medical codes at all recorded against them. A large proportion of prescriptions not associated with medical codes were repeat prescriptions.

One potential limitation of the study is that not all community antibiotic prescribing may have been fully recorded, the authors point out, as prescribed by out-of-hours services, walk-in and urgent care centres may not have made it into the electronic record. Prescribing data from specialist clinics and hospitals were not included and these services may have issued some community prescriptions.

On the other hand, as the study looked at the number of prescriptions written, not the number of antibiotic prescriptions dispensed, the study could not determine whether GPs used a delayed or deferred antibiotic prescribing strategy. If that was the case, antibiotic consumption would be slightly lower than antibiotic prescription, the authors added.

A strength of the study was that it looked at prescribing habits at the same practices over four years. Sun concluded:

Antibiotic prescribing has reduced and become more selective but substantial unnecessary antibiotic use may persist. Improving the quality of diagnostic coding for antibiotic use will help to support antimicrobial stewardship.

Read more on the King’s College London website.

The King’s Health Partners Medicine Clinical Academic Group provides a response to patients who need emergency or urgent treatment.