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

Gaps in knowledge, inhalation skills, and adherence continue to hinder effective chronic obstructive pulmonary disease (COPD) management.

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.

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.

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).

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.