Clinical Trial of Air Cleaners to Improve Indoor Air Quality and COPD Health
Study Details
Study Description
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
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.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Sham Comparator: Sham HEPA Air Cleaner Sham HEPA Air Cleaner and Delayed Intervention. 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. |
Device: Sham 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.
|
| Active Comparator: HEPA Air Cleaner HEPA Air Cleaner also containing 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. These air cleaners are suitably sized to provide clean air delivery rates for the rooms in which they will be placed. Participants will be instructed to run the air cleaners continually during the course of the study and the units will be modified to prevent them from being turned off by the participants. |
Device: HEPA Air Cleaner
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.
|
Outcome Measures
Primary Outcome Measures
- Change in Quality of Life [Change from baseline and at 6 months post randomization]
St. George's Respiratory Questionnaire (SGRQ). The total score is from 0 to 100. Higher scores indicate more limitations
Secondary Outcome Measures
- Health care utilization [Baseline 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-randomization]
Dyspnea 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 Dyspnea (mMRC) [Change from baseline and 6 months post-randomization]
Dyspnea 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 status [Change from baseline and 3 months post randomization]
Functional 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 COPD health status [Change from baseline and 6 months post randomization]
Functional 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 status [Change from baseline and 3 months post randomization]
Functional status will be assessed with the 6 minute walk test. We will assess the distance (in meters) covered a time of 6 minutes.
- Change in Functional status [Change from baseline and 6 months post randomization]
Functional status will be assessed with the 6 minute walk test. We will assess the distance (in meters) covered a time of 6 minutes.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Age ≥ 40 years,
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Physician diagnosis of COPD,
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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%,
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Tobacco exposure ≥ 10 pack-years, and
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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:
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Chronic systemic corticosteroids (≥ 3 months continuous use in past 12 months),
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Other chronic lung disease including asthma,
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Living in location other than home (e.g., long term care facility) and
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Home owner or home occupant planning to move or change residence within the study period.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Johns Hopkins University | Baltimore | Maryland | United States | 21224 |
Sponsors and Collaborators
- Johns Hopkins University
- National Institute of Environmental Health Sciences (NIEHS)
Investigators
- Principal Investigator: Nadia N Hansel, MD, MPH, Johns Hopkins University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- NA_00085617
- 1R01ES022607