Why has antibiotic prescribing for respiratory illness declined in primary care? A longitudinal study using the General Practice Research Database

Background Antibiotic prescribing by general practitioners (GPs) increased in the 1980s and peaked in 1995. Prescribing volumes subsequently fell by over a quarter between 1995 and 2000, mostly accounted for by reduced antibiotic prescribing for acute respiratory illnesses. We aimed to investigate changes in consultation rates and the proportion of consultations with antibiotics prescribed for different types of respiratory tract infections. Methods Data were derived from 108 UK general practices, covering a mean of 642685 patients, reporting data to the General Practice Research Database (GPRD) continuously between 1994 and 2000. Outcome measures: annual age-and sex-standardized consultation rates for 11 different acute respiratory infections per 1000 registered patients and proportions of these consultations resulting in an antibiotic prescription. Results The standardized consultation rate for 'any respiratory infection' declined by 35 per cent from 422 to 273 per 1000 registered patients, per year. The largest relative reductions in consultation rates were observed for 'common cold' (50 percent), 'laryngitis' (43 percent) and 'sore throat' (43 per cent). The standardized proportion of consultations that resulted in an antibiotic prescription for 'any respiratory infection' declined from 79 per cent in 1994 to 67 per cent in 2000. The largest relative reductions in antibiotic prescribing rates occurred in patients recorded as suffering from 'influenza' (52 per cent), 'upper respiratory tract infections 1 (33 per cent) and 'laryngitis' (30 per cent). Overall, antibiotic prescriptions for all acute respiratory infections declined by 45 per cent. Conclusion The reduction in antibiotic prescribing in common respiratory infections between 1994 and 2000 has occurred partly because GPs are prescribing antibiotics less frequently when patients consult but mainly because there are fewer consultations with these conditions. Further work should aim to understand the reasons for the decline in consultations for respiratory infections and whether further reductions in antibiotic prescribing are feasible.