Comorbidity in severe asthma requiring systemic corticosteroid therapy: cross-sectional data from the Optimum Patient Care Research Database and the British Thoracic Difficult Asthma Registry

ObjectiveTo determine the prevalence of systemic corticosteroid-induced morbidity in severe asthma.DesignCross-sectional observational study.SettingThe primary care Optimum Patient Care Research Database and the British Thoracic Society Difficult Asthma Registry.ParticipantsOptimum Patient Care Research Database (7195 subjects in three age- and gender-matched groups)—severe asthma (Global Initiative for Asthma (GINA) treatment step 5 with four or more prescriptions/year of oral corticosteroids, n=808), mild/moderate asthma (GINA treatment step 2/3, n=3975) and non-asthma controls (n=2412). 770 subjects with severe asthma from the British Thoracic Society Difficult Asthma Registry (442 receiving daily oral corticosteroids to maintain disease control).Main outcome measuresPrevalence rates of morbidities associated with systemic steroid exposure were evaluated and reported separately for each group.Results748/808 (93%) subjects with severe asthma had one or more condition linked to systemic corticosteroid exposure (mild/moderate asthma 3109/3975 (78%), non-asthma controls 1548/2412 (64%); p