Declared adherence of patients suffering from persistant asthma to inhaled corticoids and/or long-acting beta 2-agonists: is there a difference according to the socio-economic status? A prospective national cohort study

Context. In asthma, medication adherence is crucial for asthma control. Poor asthma control is associated with vulnerable socioeconomic conditions. Few data regarding medication adherence are available in primary care to assess the association between medication adherence and socioeconomic level (SEL). Objective. To examine whether self-reported asthma medication adherence to inhaled corticosteroids (IC) and/or long-acting beta 2 agonists (LABA) in patients with persistent asthma varies depending on SEL. Methods. Ancillary study of a French prospective cohort ASTRO-LAB, including patients suffering from persistent asthma, aged from 18 to 40. Medication adherence was assessed with the Medication Intake Survey - Asthma score (MIS-A). The SEL was estimated using Universal Health Coverage and social deprivation assessment made by the general practitioner. The analysis compared mean compliance scores over a one-year follow up. Results. The sample analysed included 395 patients, 57.97% women, and 13.67% considered as low SEL. The mean adherence scores were not significantly different between low SEL and medium/high SEL (70.11% vs 69.29%; p=0.56). Medium/high SEL patients were less often covered by special health coverage for chronic disease (OR=0.34; 95CI=0.14-0.83; p= 0.02). Conclusion. The results did not support the hypothesis of a difference in medication adherence depending on SEL. The criteria used to assess medication adherence and SEL can be improved in future studies. Medication adherence should be managed regardless of social situation.