Treatment adherence in individuals with cystic fibrosis: An Observational Study: Treatment adherence in individuals with cystic fibrosis

Abstract

Introduction: Low treatment adherence is a complex issue frequently observed in cystic fibrosis (CF) patients. Objective: To evaluate the self-reported treatment adherence rate and the rate determined based on pharmacy medication dispensation records in individuals with CF, and to investigate the association between treatment adherence and sociodemographic and clinical variables. Methods: Cross-sectional study with a consecutive sample was conducted in a CF referral center in the Northeast of Brazil. Using two methods: (1) The Morisky-Green test measured the self-reported treatment adherence for pancreatin, dornase alfa, and inhaled tobramycin; (2) dispensation records of prescribed drugs. A medication usage percentage ≥ 80% was classified as good treatment adherence. Prevalence ratios were used to assess associations between good treatment adherence and studied variables. Results: Forty-two individuals were included, 55.8% female, median age 7.3 years.  Self-reported good treatment adherence for the use of pancreatin, dornase alfa, and inhaled tobramycin were 65.8%, 50.0%, and 44.4% of the participants, respectively. According to pharmacy records, the percentages of good treatment adherence were 71.4%, 66.7%, and 52.6% for the use of dornase alfa, tobramycin, and pancreatin, respectively.  When comparing the methods, the agreement in treatment adherence rates for medication use ranged from 64.0% to 85.7%. Conclusion: Treatment adherence was low and varied by medication and methodology. Good adherence was mainly associated with younger age and the educational level.