• Asthma
• Asthma Pharmacology
• Asthma in primary care
• Clinical Epidemiology

Cross-sectional primary care record studies show that 0.9% of the adult population receive regular oral corticosteroids (OCS). Prescriptions have increased steadily over the past 20 years, presumably reflecting an increasingly elderly and infirm population.1 Respiratory conditions (mainly airway diseases) are responsible for 25–40% of these OCS prescriptions,1 ,2 by some way the largest proportion of any specialty. Against this background, it is surprising and disappointing that little is known about morbidity due to OCS usage in patients with airway disease and we remain in the unsatisfactory position of having to extrapolate from studies carried out in non-respiratory conditions. Better information in an airway disease population is important as we are approaching the biological treatment era and have within our sights treatments that offer a realistic potential to be alternatives to OCS and to allow patients already taking them to withdraw therapy safely.3–9 High quality data will be key to inform cost-effectiveness analyses for these new asthma therapies.

The paper by Sweeney et al10 in this issue of the journal is therefore timely. The authors present data from two large severe asthma populations derived from the Optimum Patient Care Research Database (OPCRD) and British Thoracic Society (BTS) Difficult Asthma Registry on the occurrence of corticosteroid associated comorbidities. OPCRD is a respiratory database that contains anonymous longitudinal medical records supplemented by information from patient-completed questionnaires from over 525 general practices across UK. This data set was used to examine potentially OCS-related morbidity in a severe asthma cohort requiring regular OCS and two age and gender-matched control cohorts: one with mild/moderate asthma requiring minimal OCS use and the other without asthma. The BTS Difficult Asthma Registry consists of anonymised data collected from Specialist UK Difficult Asthma Services. Potentially OCS-related morbidity was compared in patients with severe asthma requiring daily …