2/2 Multi-Center CLEAN AIR 2 Randomized Control Trial in COPD

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PROJECT SUMMARY. COPD is a leading cause of death and morbidity worldwide and is attributable to the aggregate burden of toxic gases and particles that individuals inhale during their lifetime. In the US, this exposure is primarily cigarette smoke; however, even after smoking cessation, patients with COPD continue to suffer respiratory morbidity. International 2022 COPD guidelines (GOLD) emphasize non-pharmacological interventions to improve health, but few evidence-based interventions exist. The indoor environment is of particular concern, as adults with COPD spend >90% of their time in the home. Particulate matter (PM) and nitrogen dioxide (NO2) are common pollutants in indoor environments and lead to worse respiratory morbidity. Our own study found that former smokers with COPD who have higher exposure to indoor pollutants have worse respiratory-specific quality of life, symptoms, and a higher risk of respiratory exacerbations. Our group recently completed a randomized controlled trial of 116 former smokers with COPD in Baltimore, MD (PI Hansel), demonstrating that the placement of two portable air cleaners with high efficiency particulate air and carbon filters can significantly reduce in-home PM and NO2 concentrations. In intention-to-treat analysis, there was a trend toward better respiratory-specific quality of life, as measured by the St. George's Respiratory Questionnaire (SGRQ) and statistically significant lower risk for moderate exacerbation, but not severe exacerbations, among those who received the active air cleaner compared to sham. Further, per-protocol analysis suggested a dose- response; among those who used the air cleaner at least 80% of the time, with a statistically significant improvement in SGRQ. Despite encouraging results, the study did not meet its primary endpoint and was not powered to determine whether air cleaner interventions can reduce moderate/severe exacerbations, including acute health care utilization. Furthermore, the trial did not include strategies to increase adherence; and results are limited to a small geographic area, limiting generalizability. The proposed study is a Phase III multi-center randomized sham-controlled environmental trial to test the effectiveness of an air cleaner intervention targeting indoor pollutants (PM and NO2) on quality of life and exacerbation risk reduction among former smokers with COPD (n~770) across multiple clinical practice locations. We will conduct cost-effectiveness analysis to ensure that study results address both clinical and economic efficacy to support policy decisions. We hypothesize that the placement of two portable air cleaners with high efficiency particulate air and carbon filters can lead to improved quality of life, reduced COPD exacerbation risk and reduced need for rescue medication use. Lastly, we hypothesize that the use of portable air cleaners is cost-effective. The trial will provide a novel approach to improve quality of life in these patients with significant morbidity; and for the prevention of COPD exacerbations, which drive the morbidity and mortality of this chronic disabling disease. In addition to addressing clinical efficacy, the study results will provide an economic evaluation to support policy decisions regarding reimbursement.