Air Purification for Asthma

Overseen By Meredith C. McCormack, MD, MHS

Age: < 18

Sex: Any

Trial Phase: Academic

Sponsor: Johns Hopkins University

Disqualifiers: Pulmonary, Cardiac, Underweight, Pregnancy, others

Compensation: Varies

Number of Visits: 5

Duration: 12 weeks

198 Participants Needed

Trial Summary

What is the purpose of this trial?

Background: Asthma and obesity are public health crises that have concurrently risen over the past decades, affecting millions of children in the United States and disproportionately affecting low-income minority children in urban areas. The same children at highest risk for asthma and obesity also have greater exposure to indoor and outdoor pollution. Emerging evidence suggests that obesity may confer increased susceptibility to health effects of air pollution. Methods: Aiming to provide causal-level evidence of these observational findings, we propose a home intervention study to 1) test whether targeted reductions of indoor Particulate Matter (PM) concentrations improve the respiratory health of overweight inner-city children with asthma more than that of lean inner-city children with asthma and 2) investigate mediators of susceptibility to indoor PM among overweight versus lean children with asthma. We will accomplish these aims using a 1:1 randomized controlled trial of 200 children with persistent asthma (half normal weight, half overweight) living in Baltimore City. Participants will be randomized to receive either two active air purifiers containing high-efficiency particulate air (HEPA) filters or two sham air purifiers with their filters removed. Implications: If the aforementioned observational findings are confirmed, implications will be directly relevant to the over 170 million children around the world now estimated to be overweight or obese.

Do I need to stop my current medications for this trial?

The trial information does not specify whether you need to stop taking your current medications. It is best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment Active Air Purifier for asthma?

Research shows that using air purifiers can help reduce indoor air pollutants and improve asthma control in children. Additionally, a study found that using a specific type of air cleaner reduced the need for asthma medications and improved airway responsiveness in patients. ^{1 2 3 4 5}

Is air purification safe for humans?

Research on air purifiers, including HEPA filters, shows they are generally safe for use in homes, as they help reduce indoor air pollutants without reported harmful effects on humans. ^{1 6 7 8 9}

How does the Active Air Purifier treatment for asthma differ from other treatments?

The Active Air Purifier treatment is unique because it focuses on improving indoor air quality by reducing allergens and airborne particles, which can help control asthma symptoms. Unlike traditional asthma medications that are ingested or inhaled, this treatment works by cleaning the air in the patient's environment, potentially reducing the need for medication. ^{3 5 10 11 12}

Research Team

Meredith C. McCormack, MD, MHS

Principal Investigator

Johns Hopkins University, Pulmonary and Critical Care Medicine

Eligibility Criteria

This trial is for children aged 8-17 living in Baltimore with persistent asthma, who are either of normal weight or overweight. They must spend most nights at home and have had an asthma exacerbation within the last year. Kids can't join if they're underweight, pregnant, smoke, have serious lung/heart conditions, or live in homes in disrepair.

Inclusion Criteria

My condition has worsened in the last year.

I have long-term asthma.

No plans to move during the study

Exclusion Criteria

You are considered to be very thin based on your body mass index (BMI).

I have a serious heart or lung condition.

Home not appropriate candidate due to disrepair

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Baseline Assessment

Home and clinical assessments are conducted before randomization

1 week

1 visit (in-person), 1 home assessment

Treatment

Participants receive either active or placebo air purifiers for 12 weeks

12 weeks

2 home assessments, 3 clinic visits

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

1 visit (in-person)

Treatment Details

Interventions

• Active Air Purifier
• Placebo Air Purifier

Trial Overview The AIRWEIGHS study tests whether using air purifiers with HEPA filters at home can better improve respiratory health for overweight kids with asthma compared to those of normal weight. It's a randomized trial where half get real air purifiers and half get placebo ones without filters.

Participant Groups

Group I: Active Air Purifier Active Control 1 Intervention

Two portable air purifiers containing HEPA filters will be placed in the bedroom and room where the participant reports spending the most time. We have chosen to deploy two air purifiers because we have observed a 50% reduction in indoor PM concentrations with two air purifiers. Participants will be instructed to run the air purifiers continually. Participants will receive educational materials about environmental factors that are important for asthma health and environmental modification strategies. Participants will also receive educational materials about health benefits of maintaining a normal weight.

Group II: Placebo Air Purifier Placebo Group 1 Intervention

Homes in the control group will receive placebo air purifiers that have the internal air filters removed, but which will run normally. Participants will receive educational materials about environmental factors that are important for asthma health and environmental modification strategies, and educational materials about health benefits of maintaining a normal weight. At the end of the study, participants in the control group will receive active air purifiers. A control group is needed to ensure that reduced pollutant levels and health effects are not due to temporal trends and 'placebo effects' of being enrolled in an intervention trial. Participants will also be informed that being in the study does not prevent them from purchasing and using air cleaners during the study period.

Who Is Running the Clinical Trial?

Johns Hopkins University

Lead Sponsor

Trials

2,366

Recruited

15,160,000+

National Institute of Environmental Health Sciences (NIEHS)

Collaborator

Trials

294

Recruited

1,233,000+

Findings from Research

In a study involving 225 children aged 6 to 12 with asthma exposed to secondhand smoke, the use of HEPA air cleaners resulted in 42 fewer unscheduled asthma visits, indicating a significant reduction in asthma-related emergencies (P = .043).

The intervention group experienced a 25% reduction in airborne particles, while the control group only saw a 5% reduction, suggesting that HEPA air cleaners effectively lower harmful particulate levels, although no significant differences were found in reported asthma symptoms or other biomarkers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of HEPA air cleaners on unscheduled asthma visits and asthma symptoms for children exposed to secondhand tobacco smoke. Lanphear, BP., Hornung, RW., Khoury, J., et al.[2021]

In a study involving 71 households with children aged 6-12 who have asthma, the use of portable HEPA air cleaners significantly reduced PM2.5 levels by 60% in sleeping areas and 42% in living areas after one year, compared to control homes.

Despite the reduction in PM2.5, the HEPA air cleaners did not lead to a significant decrease in ammonia (NH3) levels, indicating that while they are effective for particulate matter, they may not address all air quality concerns.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effectiveness of portable HEPA air cleaners on reducing indoor PM2.5 and NH3 in an agricultural cohort of children with asthma: A randomized intervention trial. Riederer, AM., Krenz, JE., Tchong-French, MI., et al.[2021]

The use of HEPA air filters significantly reduced indoor concentrations of traffic-related airborne particles, which are linked to asthma issues in children.

Children with poorly controlled asthma showed notable improvements in asthma control and quality of life after using HEPA filtration, indicating its potential as an effective intervention for managing asthma symptoms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

HEPA filtration improves asthma control in children exposed to traffic-related airborne particles. James, C., Bernstein, DI., Cox, J., et al.[2021]

References

1. Korea (South) pubmed.ncbi.nlm.nih.gov

Effects of Indoor Air Purifiers on Children with Asthma. [2020]

2. Singapore pubmed.ncbi.nlm.nih.gov

Efficacy of air purifier therapy for patients with allergic asthma. [2022]

3. United States pubmed.ncbi.nlm.nih.gov

Effect of air filtration systems on asthma: a systematic review of randomized trials. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

The efficacy of the Dyson air purifier on asthma control: A single-center, investigator-led, randomized, double-blind, placebo-controlled trial. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Laminar flow air cleaner bed attachment: a controlled trial. [2007]

6. United States pubmed.ncbi.nlm.nih.gov

Effects of HEPA air cleaners on unscheduled asthma visits and asthma symptoms for children exposed to secondhand tobacco smoke. [2021]

7. England pubmed.ncbi.nlm.nih.gov

Effectiveness of portable HEPA air cleaners on reducing indoor PM2.5 and NH3 in an agricultural cohort of children with asthma: A randomized intervention trial. [2021]

8. England pubmed.ncbi.nlm.nih.gov

HEPA filtration improves asthma control in children exposed to traffic-related airborne particles. [2021]

9. England pubmed.ncbi.nlm.nih.gov

Efficacy of indoor air purification in treating Artemisia (mugwort) pollen allergic rhinitis: study protocol for a randomised controlled trial. [2019]

10. England pubmed.ncbi.nlm.nih.gov

Reducing patients' exposures to asthma and allergy triggers in their homes: an evaluation of effectiveness of grades of forced air ventilation filters. [2021]

11. England pubmed.ncbi.nlm.nih.gov

Allergen reduction measures in houses of allergic asthmatic patients: effects of air-cleaners and allergen-impermeable mattress covers. [2019]

12. Canada pubmed.ncbi.nlm.nih.gov

The Efficacy of the Dyson Air Purifier in Improving Asthma Control: Protocol for a Single-Center, Investigator-Led, Randomized, Double-Blind, Placebo-Controlled Trial. [2021]