HEPA air purifiers improved respiratory outcomes in former smokers with COPD, with the most benefit found in those who spent more time indoors, a new study found.
“Although outdoor air pollution has known adverse respiratory effects, the indoor environment is of particular concern, as most individuals with COPD spend the majority of their time indoors and indoor air particulate matter concentrations in homes of former smokers with COPD have been associated with worse respiratory symptoms, worse quality of life and increased respiratory exacerbations,” Nadia N. Hansel,MD, MPH, professor of medicine at Johns Hopkins University School of Medicine and from the department of environmental health and engineering at Johns Hopkins Bloomberg School of Public Health, and colleagues wrote.
The randomized controlled CLEAN AIR STUDY included 116 former smokers with moderate to severe COPD (mean age, 65.7 years; 51.7% women; 84.5% completed the study). All participants were randomly assigned to use an active portable high-efficiency particulate air (HEPA) cleaner (n = 58; Austin Air Cleaners) or a sham device that had internal HEPA and carbon filters removed (n = 58). Participants were asked to place the air cleaner in their bedroom and other room they reported spending the most time. Follow-up was 6 months. The intention-to-treat analysis included all participants, and the per-protocol analysis included participants with at least 80% adherence.
“Portable air cleaner intervention strategies are practical and easily implemented by individuals at the household level, and improve respiratory symptoms in other chronic respiratory diseases, including in children with asthma; however, such intervention studies have not been conducted in COPD and it is unknown whether use of portable air cleaners in homes of individuals with COPD can reduce indoor pollutants and improve COPD outcomes,” the researchers wrote.