Motivational interviewing and air cleaners for smokers with COPD (MOVE): a randomized, double-blind,...

Indoor particulate matter (PM) is linked to worse respiratory outcomes in adults with chronic obstructive -pulmonary disease (COPD). It is unclear if reducing indoor pollutants can improve respiratory health among current smokers.

This study aimed to assess whether a multicomponent environmental intervention to improve home air quality (PM and secondhand smoke [SHS] exposure) improves respiratory morbidity among current smokers with COPD.

Current smokers with moderate-to-severe COPD were randomized to receive active portable high-efficiency -particulate air cleaners and motivational interviewing (MI) for PM and SHS reduction, respectively; or sham air cleaners -without MI. The primary outcome was 6-month change in Saint George's Respiratory Questionnaire. Secondary outcomes were respiratory symptoms, exacerbation risk, and lung function.

Among 121 randomized participants, 99 completed the study. The active intervention resulted in reduced PM levels compared to control, but no reduction in indoor SHS exposure. Those in the active arm showed a clinically and statistically significant improvement in total Saint George's Respiratory Questionnaire score compared to control (ß -4.4 [95% confidence interval, -8.2 to -0.5]; P = .025). Secondary analyses indicated significant improvement in respiratory symptoms (dyspnea and cough) and health status as measured by COPD Assessment Test and clinical COPD questionnaire among the active group (vs. control). There was no significant difference in forced expiratory volume in 1 second change, sputum symptoms, or odds of exacerbations between groups.

This study is the first to demonstrate potential health benefits from an environmental intervention in active smokers with COPD, most likely attributable to PM reduction associated with portable high-efficiency particulate air cleaner use.