Long-term adherence to inhaled corticosteroids in children with asthma: Observational study.

Introduction: Non-adherence to daily controller medication in childhood asthma is strongly dependent on potentially modifiable factors such as parental illness perceptions and medication beliefs. The extent to which adherence in children can be improved by addressing modifiable determinants of non-adherence has not been studied to date, however. We assessed long-term adherence and its determinants in children with asthma enrolled in a comprehensive asthma care program employing shared decision making with parents.

Methods: Observational study in 135 children 2-12 years of age with asthma attending a hospital-based outpatient clinic. One-year adherence to inhaled corticosteroids was measured by electronic devices. Parental illness perceptions and medication beliefs, and asthma control were assessed by validated questionnaires.

Results: Median (interquartile range) adherence was 84% (70-92%). 55 children (41%) did not achieve the pre-defined level of good adherence (≥80%) and this was associated with poorer asthma control. Parental perceived medication necessity was high, with a median (interquartile range) BMQ necessity score of 17 (16-20). Parents' replies to the five key questions on the core issues of the program showed high concordance of their illness perceptions and medication beliefs with the medical model of asthma and its treatment. Differences in these perceptions between adherent and non-adherent families were small and non-significant.

Conclusions: Poor adherence may persist in children despite a high level of concordance between medical team and parents on illness perceptions and medication beliefs, even in the absence of socio-economic barriers to good adherence. Achieving good adherence in all children is a complex task, requiring interventions not covered in current guidelines of managing asthma in children.