Relationship between self-related adherence to asthma and asthma control in adult patients

Abstract

Objective: To assess the self-reported adherence to asthma treatment in outpatients with asthma, to investigate the relationship between adherence and asthma control. In addition, it aimed to describe the characteristics of patients with poor adherence. Methods: In a cross-sectional study we recruited patients aged 14 years and older with confirmed asthma diagnosis from the outpatient asthma clinic of Hospital de Clínicas de Porto Alegre, Brazil. They underwent an evaluation by a general questionnaire, an asthma control questionnaire (based on Global Initiative for Asthma - GINA 2011), an adherence questionnaire and pulmonary function tests. Poor adherence was defined as the reporting of non-use or use less than 5 times in the week of devices containing inhaled corticosteroids. Results: Out of 275 patients studied, 239 (86.9%) were considered with high level of adherence and 36 (13.1%) with poor adherence. There was a significant association between asthma control and self-reported adherence to treatment (p=0.005), so that most patients with high level of adherence kept their disease under control, whereas most patients with poor adherence had uncontrolled status. Logistic regression analysis identified that age was inversely associated with poor adherence (odds ratio=0.98, 95% confidence interval 0.95-0.99, p=0.016). Conclusions: Self-reported adherence to treatment of patients attending an asthma outpatient clinic was elevated (86.9%). The poor adherence was associated with uncontrolled asthma. Younger patients were more likely to be poorly adherent with treatment.