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Clinical Trial of Air Cleaners to Improve Indoor Air Quality and COPD Health

Clinical Trial of Air Cleaners to Improve Indoor Air Quality and COPD Health

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02236858
Enrollment
142
Registered
2014-09-11
Start date
2014-03-31
Completion date
2021-09-10
Last updated
2021-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic Obstructive Pulmonary Disease (COPD)

Keywords

COPD

Brief summary

Objectives (include all primary and secondary objectives) Specific Aim #1: To determine whether an air cleaner intervention to improve home air quality will improve respiratory symptoms, quality of life, lung function and reduce risk of exacerbations in former smokers with COPD. Hypothesis: An intervention using high-efficiency particulate air (HEPA) and carbon filter air cleaners in homes of former smokers with COPD will improve respiratory symptoms, quality of life, and lung function and reduce risk of COPD exacerbations compared with placebo (sham air cleaners). Specific Aim #2: To determine whether an air cleaner intervention to improve home air quality will be associated with intermediate outcome measures known to be linked with long term outcomes in COPD, including airway and systemic markers of inflammation and oxidative stress, in former smokers with COPD. Hypothesis 2: An intervention using HEPA and carbon filter air cleaners in homes of formers smokers with COPD will be associated with lower levels of markers of inflammation and oxidative stress known to be associated with adverse outcomes in patients with COPD.

Detailed description

This research is being done to learn whether an air cleaner intervention to improve home air quality (particulate matter (PM) and nitrogen dioxide (NO2) reduction) will improve respiratory symptoms, quality of life, lung function, and reduce risk of exacerbations in former smokers with COPD. The investigators will place air pollution monitors in the home to measure the air quality over five 1-week periods (at 3 month and 1 week pre-intervention, and 1 week, 3 months and 6 months post-intervention). During each week of monitoring, the investigators will ask that a diary be kept of breathing and how the participants are feeling every day. Participant will have 5 home visits and 5 clinic visits and monthly telephone calls during this time to see how the participant is feeling. One week after each home visit, the monitoring equipment will be picked up. After the 2nd monitoring period, active or sham air cleaners will be placed in home.

Interventions

Air cleaners containing HEPA and carbon filters (Austin HealthMate HM400) and capable of removing PM and NO2 will be placed in the bedroom and room where the participant reports spending the most time.

DEVICESham HEPA Air Cleaner

Homes in the control group will receive sham air cleaners that have the internal HEPA and carbon filters removed, but which will run normally, including similar noise, airflow and overall appearance compared to active air cleaners, thus blinding participants to filter status.

Sponsors

National Institute of Environmental Health Sciences (NIEHS)
CollaboratorNIH
Johns Hopkins University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender
ALL
Age
40 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age ≥ 40 years, * Physician diagnosis of COPD, * Global Initiative for Obstructive Lung Disease (GOLD) Stage II-IV disease with Forced Expiratory Volume (FEV1)/ Forced Vital Capacity (FVC) ≤70% and FEV1 (% predicted) \<80%, * Tobacco exposure ≥ 10 pack-years, and * Former smoker. We will employ a combination of self-report and a biochemical marker to identify former-smokers. Exhaled CO (eCO) will be used as a marker of smoking status, as it is easy to perform, provides immediate data and is non-invasive. Former-smokers will be those who report no current smoking in the past 1 year AND have exhaled CO levels ≤ 6ppm. This threshold was chosen to maximize the chance of distinguishing true smokers and ex-smokers (\>95%).

Exclusion criteria

* Chronic systemic corticosteroids (≥ 3 months continuous use in past 12 months), * Other chronic lung disease including asthma, * Living in location other than home (e.g., long term care facility) and * Home owner or home occupant planning to move or change residence within the study period.

Design outcomes

Primary

MeasureTime frameDescription
Change in Quality of LifeChange from baseline and at 6 months post randomizationSt. George's Respiratory Questionnaire (SGRQ). The total score is from 0 to 100. Higher scores indicate more limitations

Secondary

MeasureTime frameDescription
Health care utilizationBaseline through end of study (approximately 6 months post-randomization)Aggregate Exacerbations including (need for oral corticosteroids or antibiotics for worsening respiratory symptoms, emergency department (ED) visit or hospitalization). During this 6 months exacerbations will be collected at monthly telephone calls and at 3 and 6 month clinic visits. Whether an exacerbation occurred over this 6 month period will be assessed.
Change in Dyspnea (mMRC)Change from baseline and 3 months post-randomizationDyspnea will be assessed using the modified medical research Council questionnaire (mMRC). The total score is from 0 (no dyspnea) to 2 (severe dyspnea).
Change in COPD health statusChange from baseline and 3 months post randomizationFunctional status will be assessed with the COPD assessment test (CAT). The total score is from 0 to 40. Higher scores indicate worse COPD control
Change in Functional statusChange from baseline and 3 months post randomizationFunctional status will be assessed with the 6 minute walk test. We will assess the distance (in meters) covered a time of 6 minutes.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 10, 2026