A study of a multi-level intervention to improve non-adherence in difficult to control asthma

Abstract

Background: Difficult to control asthma accounts for significant morbidity and healthcare cost, and non-adherence to medication is a common cause. It remains unclear if targeting non-adherence in this population improves healthcare outcomes.

Methods: All subjects were referred to a Specialist Difficult Asthma Service (60% from Respiratory physicians); poor adherence was identified using prescription refill records for inhaled combination therapy. A sequential 2 phase study examined the effect of identifying and targeting non-adherence to inhaled long-acting β-agonist/inhaled steroid combination therapy; phase 1 - an observational study utilising objective measures of non-adherence to facilitate a medical concordance discussion followed by phase 2, a 12 month prospective single blind randomised controlled trial where subjects with persistent poor adherence were randomised to a nurse-led menu driven intervention.

Results: A total of 239 patients were assessed; 31 of 83 subjects (37%) who were initially non-adherent, significantly improved adherence after concordance interview, with reduced prescribed daily dose of ICS (data p<0.001), rescue prednisolone courses (data, p<0.001) and hospital admissions (data, p=0.006). With the menu driven intervention, adherence also improved (intervention 37.6% to 61.9%, control group 31.7% to 28.8%) with reduced maintenance oral steroid dose in subjects on maintenance steroids.

Conclusion: Poor adherence in difficult-to control asthma is common, but when identified and targeted can be improved and this is associated with large improvements in important healthcare outcomes. Previous nihilism towards non-adherence in this population is not supported by this study.