Predictors of Treatment Adherence in Outpatients With Chronic Obstructive Pulmonary Disease: Cross-Sectional Study

Abstract Background Gaps in knowledge, inhalation skills, and adherence continue to hinder effective chronic obstructive pulmonary disease (COPD) management. Objective The study was conducted to describe the status of COPD-related knowledge, practical skills for inhalation and breathing exercises, and treatment adherence among patients with COPD and to identify the relationships between these variables. Methods A cross-sectional study was conducted among 420 outpatients with COPD. Data were collected in 2 rounds, including interviews to assess patients’ knowledge and treatment adherence and checklist-based observations of patients’ practical skills. Multivariable logistic regression analysis was used to evaluate the associations between knowledge and practical skills and the status of treatment adherence. Results A total of 420 outpatients with COPD were included; 331 (78.8%) participants had inadequate COPD-related knowledge, 268 (63.8%) demonstrated adequate practical skills, and 155 (36.9%) achieved overall treatment adherence. In multivariable logistic regression, higher knowledge scores were associated with better treatment adherence (adjusted odds ratio [aOR] 1.20, 95% CI 1.06‐1.31; P =.001). Participants who correctly performed inhaler-use techniques were more likely to be adherent than those with incorrect technique (aOR 3.10, 95% CI 2.10‐4.70; P =.001). Likewise, adequate breathing-exercise skills were associated with higher adherence (aOR 1.70, 95% CI 1.08‐2.71; P =.02). Conclusions Higher COPD-related knowledge and better practical skills in inhaler use and breathing exercises were associated with better treatment adherence among outpatients with COPD. Because of the cross-sectional design, these findings indicate associations rather than causal relationships. These observed associations may help inform future intervention studies evaluating patient education and skill-based training, although their effectiveness should be confirmed in longitudinal or interventional studies.