Predictors of Adherence to Inhaled Medications

To the Editor:—The study of predictors of adherence to inhaled medications by Heutsch et al.¹ addresses a highly important problem with wide implications surpassing the treatment of chronic obstructive pulmonary disease (COPD) alone.

However, despite the large patient samples studied and the many variables included, it suffers from one significant limitation.

Much like the child looking for the coin he lost under the lamppost because that’s where the light is, the researchers highlight the field their study was able to measure, but neglect all other aspects crucial to medication adherence in COPD but less amenable to their research methodology.

As found in other chronic illnesses,^2,3 the nature of the patient–physician communication and patient–physician relationship was found to be a major determinant of patient satisfaction, trust, health literacy, adherence and outcomes.

In another study of veterans with COPD, clinician behaviors that included listening, caring, and attentiveness—markers of excellent patient–clinician communication and patient-centered care, were associated with patients’ reports of high-quality health-care delivery and confidence of dealing with their disease.⁴

Although drug adherence was not directly measured in this study, it is a likely consequence of improved patient-centered care and participatory decision-making, as demonstrated in patients with asthma,⁵ and should be acknowledged and targeted in future studies.