Insights into Poor Adherence with COPD Inhaled Therapy: A Post Hoc Analysis of 4537 Patients from the CLAVE Study

This study aimed to identify major contributors to poor adherence to inhaled therapy in a large cohort of patients with severe chronic obstructive pulmonary disease (COPD).

This was a post hoc analysis of 4801 patients with severe COPD included in an observational, cross-sectional, multicenter study (the CLAVE Study) in which clinical control criteria were used to evaluate the control of COPD in Spain. All patients had a post-bronchodilator forced expiratory volume in 1 second (FEV₁)<50% predicted and received inhaled medication. The test of adherence to inhalers (TAI) was used to assess the types of non-adherence.

The TAI questionnaire was completed by 4537 patients, with an overall rate of non-adherence of 39.0% (n=1770). The degree of adherence was intermediate in 887 (19.6%) and poor or non-adherent in 883 (19.5%). The rates of non-adherent behaviors were 37.1% for erratic, 25.0% for deliberate and 13.6% for unconscious (unwitting). Current smoking and patient's care in the primary care setting showed the highest odds ratio in the regression analysis. Poorly controlled disease, symptomatic COPD, and exacerbator and eosinophilic phenotypes were significantly associated with poor adherence.

Non-adherence to inhaled therapy was found in 39% of patients with severe COPD attended in real-life conditions. Notably, unconscious type of non-adherence found in 13.6% of the overall study population increasing to 31% in patients with poor adherence highlights the need of consistently ensuring that patients understand their therapeutic regimen and use devices correctly over the entire follow-up of COPD.