Differences in medication adherence are associated with beliefs about medicines in asthma and COPD.

Adherence to medication is crucial for achieving treatment control in chronic obstructive lung diseases. This study refers to the "necessity-concerns framework" and examines the associations between beliefs about medicines and self-reported medication adherence in people with chronic obstructive lung disease. 402 patients (196 with asthma, 206 with COPD) participated in the study and completed a questionnaire comprising the "Beliefs about Medicines-Questionnaire" (BMQ) and the "Medication Adherence Report Scale" (MARS). Multivariable logistic regression analyses with the BMQ-subscales as explanatory and the dichotomized MARS-score as dependent variable were computed for the asthma and the COPD sample, respectively, and adjusted for potentially confounding variables. 19% of asthma patients and 34% of COPD patients were completely adherent to their prescribed medication. While specific beliefs about the necessity of medicines were positively associated with medication adherence both in patients with asthma and with COPD, general beliefs about harm and overuse of medicines by doctors were negatively associated with medication adherence only among patients with asthma. The findings of this study suggest that patients' specific beliefs about the necessity of medicines represent an important modifiable target for improving patient-doctor consultations when prescribing medicines.