Medication adherence in patients with severe asthma prescribed oral corticosteroids in the U-BIOPRED cohort.
Whilst estimates of sub-optimal adherence to oral corticosteroids in asthma range from 30 to 50%, no ideal method for measurement exists; the impact of poor adherence in severe asthma is likely to be particularly high.1. What is the prevalence of suboptimal adherence detected using self-reporting and direct measures? 2. Is suboptimal adherence associated with disease activity?Data were included from individuals with severe asthma taking part in the U-BIOPRED study prescribed daily oral corticosteroids. Participants completed the MARS, a five-item questionnaire used to grade adherence on a scale from 1 to 5, and provided a urine sample for analysis of prednisolone and metabolites by liquid-chromatography mass spectrometry.Data from 166 participants were included in this study, mean (SD) age 54.2 (11.9) years, FEV1 65.1 (20.5) % predicted, 58% female. 37% completing the MARS reported sub-optimal adherence, and 43% with urinary corticosteroid data did not have detectable prednisolone or metabolites in their urine. Good adherence by both methods was detected in 35% participants who had both performed; adherence detection did not match between methods in 53%. Self-reported high-adherers had better asthma control and quality of life, whereas directly-measured high-adherers had lower blood eosinophils.Low adherence is a common problem in severe asthma, whether measured directly or self-reported. We report poor agreement between the two methods suggesting some disassociation between self-assessment of medication adherence and regular oral corticosteroid use, which suggests that each approach may provide complementary information in clinical practice.
Authors: Fahad H Alahmadi, Andrew J Simpson, Cristina Gomez, Magnus Ericsson, John-Olof Thörngren, Craig Wheelock, Dominic E Shaw, Louise J Fleming, Graham Roberts, John Riley, Stewart Bates, Ana R Sousa, Richard Knowles, Aruna T Bansal, Julie Corfield, Ioannis Pandis, Kai Sun, Per S Bakke, Massimo Caruso, Pascal Chanez, Barbro Dahlén, Ildiko Horvath, Norbert Krug, Paolo Montuschi, Florian Singer, Scott Wagers, Ian M Adcock, Ratko Djukanovic, Kian Fan Chung, Peter J Sterk, Sven-Erik Dahlen, Stephen J Fowler, U-BIOPRED Study Group