ClinicalTrials.gg
Status unknownNCT03282864Updated Mar 23, 2020

The Impact of Air Filtration on Asthmatic Children

An interventional study of Bedroom air filtered by an air filtration device to remove airborne pollutants in Asthma in Children, sponsored by Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine. Status unknown at 1 site in China. Open to participants aged 5 Years to 14 Years. Per ClinicalTrials.gov, last updated 2020-03-23.

Sponsored by Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine · Not applicable, Interventional, and Prevention

The sponsor has not verified this record recently (last verified Mar 2020), so the status shown — last known as Active, not recruiting — may be out of date.

From the registry’s dates

  • Registered 7 months after the study started (first participant enrolled Jan 2017, registered Aug 2017).
Phase
Not applicable
Study type
Interventional
Enrollment
43
Allocation
Randomized
Ages
5 Years to 14 Years
Sex
All
01

Study summary

This study uses a crossover study design to examine the impact of a two-week bedroom based indoor air filtration on the concentration of indoor airborne pollutants, personal exposure to airborne pollutants and health indicators among asthmatic children living in Shanghai, China

Read the detailed description

This study recruited asthmatic children aged 5 to 14 who were living in Shanghai, China. Every study subject had the air in their bedroom processed by an air filtration device (with a pre-filter, a HEPA filter and an active carbon filter) for two weeks (active comparator arm), processed by a placebo air filtration device (which did not possess the HEPA filter and active carbon filters) for two weeks (placebo arm), and underwent a two-week washout period (no use of air filtration device) between the two intervention periods. The doors and windows of the bedroom were instructed to be kept closed during the intervention periods. The sequence of being in the active comparator arm and the placebo arm was randomized for each subject. The subject, their guardian and researchers who have direct interaction with the study subjects do not know this sequence until after the end of the study.

The study protocol was approved by IRB at Shanghai First People's Hospital, Duke University and University of Wisconsin at Madison. A sample size of 40 was calculated using fractional exhaled nitric oxide (FeNO) as the primary outcome where statistical significance was set at 0.05, power at 90%, and between-subject variance and covariance were estimated from existing literature. Four additional subjects were added to the estimated sample size of 40 to account for potential dropouts. Subjects were recruited from patients who attended the outpatient clinic of the Pediatrics Department of Shanghai First People's Hospital (south section) by Dr. Zhen Li and Dr. Junfeng Zhang's team. Assent was obtained from all study subjects and written informed consent was obtained from their guardians.

During the study, Dr. Michael Bergin's team and Dr. Yinping Zhang's team installed the air filtration devices in the subject's bedroom and measured the indoor concentration, outdoor concentration and personal exposure to airborne pollutants including PM2.5, ozone and volatile organic compounds. Dr. James Schauer's team analyzed the physical, chemical and bioactivity of the airborne particles collected and had no direct contact with the study subjects.

Each subject attended 5 clinical visits at the Shanghai First People's Hospital (South Section) accompanied by their guardian where clinical assessment (of lung function, fractional exhaled nitric oxide, asthma symptom blood draw) was performed by Drs. Zhen Li and Feng Li's team, and the collection of biological media (urine, saliva and nasal fluid) was conducted by Dr. Junfeng (Jim) Zhang's team. In addition, subjects were instructed to measure the peak expiratory flow (PEF) at 7am and 9pm daily and recorded their asthma symptoms at home with the assistance from their guardian(s). The biological media (urine, saliva and nasal fluid) collected was subsequently analyzed by Dr. Junfeng (Jim) Zhang's team for health indicators.

Each subject had access to the result of clinical assessment and health indicator in biological media, as well as free consultation from the medical teams of Drs. Zhen Li and Feng Li. Every subject was remunerated with 1000RMB (equivalent to 152 US dollars) and given a peak expiratory flow meter (worth less than 10 US dollars). All information collected from study subjects were recorded under their subject ID number and kept confidential. Only de-identified data was shared between collaborating investigators. Statistical analysis including mixed-effects models will be conducted on the data collected.

02

Conditions studied

  • Asthma in Children

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Keywords

  • asthma
  • air pollution
  • air filtration
  • indoor air quality
  • respiratory health
03

In context

Asthma

4,010 studies on the registry are indexed under Asthma; 514 are open to participants now.

This study's enrollment of 43 is below the median of 83 across 2,814 interventional studies indexed under Asthma.

Browse Asthma studies →

Lead sponsor

Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine is the lead sponsor of 182 studies on the registry; 108 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
5 Years to 14 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

An eligible child is defined as:

  • Aged between 5 and 14
  • Have physician-diagnosed asthma
  • Had at least one asthma attack during the past year

An eligible household is defined as:

  • Has an eligible child
  • Located in Shanghai, China

Exclusion criteria

Exclusion Criteria:

  • Children who were current smokers or have diseases other than asthma are exclude from study participation
05

Study design

Phase
Not applicable
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Triple (Participant, Care provider, Outcomes assessor)
Enrollment
43 participants (actual)

Study arms

  • Active comparator
    Bedroom air filtered by an air filtration device

    The air in the bedroom of study subjects in the active comparator arm was filtered by an air filtration device which processed air through a pre-filter, a high efficiency particular air (HEPA) filter and an active carbon filter. The duration of being in the active comparator arm was 2 weeks.

    Device: Bedroom air filtered by an air filtration device to remove airborne pollutants

  • Placebo comparator
    Bedroom air filtered by a placebo air filtration device

    The air in the bedroom of subjects in the placebo arm was filtered by a placebo air filtration device that looked identical to the real air filtration device but did not possess the HEPA filter and the active carbon filter. The duration of being in the placebo arm was 2 weeks.

    Device: Bedroom air filtered by an air filtration device to remove airborne pollutants

Interventions

  • DeviceBedroom air filtered by an air filtration device to remove airborne pollutants

    The air in the bedroom of study subjects in the active comparator arm was processed by an air filtration device which pulled air through a pre-filter, a high efficiency particular air (HEPA) filter and an active carbon filter continuously. The air in the bedroom of subjects in the placebo arm was processed by a placebo air filtration device that looked identical to the real air filtration device but did not possess the HEPA filter and the active carbon filter. Each subject was assigned to the active comparator arm and the placebo arm in a randomized order with a two-week washout period scheduled in-between. The subjects, their guardians and the study staff that assessed the health indicators of the subjects were blinded to this order till the end of the study.

06

What researchers measure

Primary outcomes

  1. Fractional exhaled nitric oxide (FeNO)

    Fractional exhaled nitric oxide (FeNO) was measured using the NIOX machine

    Time frame: Change of FeNO after the end of the two-week intervention compared to the start of the two-week intervention period

Secondary outcomes

  1. Asthma symptoms

    Asthma symptom was evaluated by the Asthma Control Test (ACT) questionnaire

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  2. Peak expiratory flow (PEF)

    The maximum speed of exhalation (PEF) was measured by a handheld PEF meter (Koka Peak Expiratory Flow Meter)

    Time frame: Measured at 7am and 9pm daily during the two-week intervention

  3. Lung function

    Lung function was assessed by spirometry (Jaeger MasterScreen™ PFT system) and impulse oscillometry (Jaeger MasterScreenTM IOS).

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

Other outcomes

  1. Malondialdehyde (MDA) concentration in urine

    Malondialdehyde (MDA) concentration in urine was measured using the thiobarbituric acid derivatization method and high-performance liquid chromatography (HPLC)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  2. 8-OHdG concentration in urine

    Concentration of 8-hydroxydeoxyguanosine (8-OHdG) in urine was measured by solid phase extraction and liquid chromatography-mass spectrometry (LC-MS)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  3. Malondialdehyde (MDA) concentration in nasal fluid

    Malondialdehyde (MDA) concentration in nasal fluid was measured using the thiobarbituric acid derivatization method and high-performance liquid chromatography (HPLC)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  4. Malondialdehyde (MDA) concentration in saliva

    Malondialdehyde (MDA) concentration in saliva was measured using the thiobarbituric acid derivatization method and high-performance liquid chromatography (HPLC)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  5. Interleukin-6 level in saliva

    The concentration of interleukin-6 in saliva was measured by enzyme-linked immunosorbent assay (ELISA)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  6. Eosinophil cationic protein concentration in saliva

    The concentration of eosinophil cationic protein in saliva was measured by enzyme-linked immunosorbent assay (ELISA)

    Time frame: Within 24 hours before the start of intervention and within 24 hours after the end of intervention

  7. Blood eosinophil

    Blood eosinophil was assessed using the blood routine test

    Time frame: Only once at the time of enrollment into the study

  8. Allergen profile

    The IgE antibody for 19 allergens were assessed using serum samples from study subjects.

    Time frame: Only once at the time of enrollment into the study

  9. Chemical exposure

    Personal exposure to chemicals including flame retardant and organophosphates was assessed using silicone wristbands that were worn on the wrist of study subjects for 1 week

    Time frame: During 1 week of the study

07

Study locations

1 site
  • Shanghai General Hospital
    Shanghai, Shanghai Municipality 201620, China
08

References and documents

Publications

  • Cui X, Li Z, Teng Y, Barkjohn KK, Norris CL, Fang L, Daniel GN, He L, Lin L, Wang Q, Day DB, Zhou X, Hong J, Gong J, Li F, Mo J, Zhang Y, Schauer JJ, Black MS, Bergin MH, Zhang J. Association Between Bedroom Particulate Matter Filtration and Changes in Airway Pathophysiology in Children With Asthma. JAMA Pediatr. 2020 Jun 1;174(6):533-542. doi: 10.1001/jamapediatrics.2020.0140. PubMed 32250418 ↗
  • Brehmer C, Norris C, Barkjohn KK, Bergin MH, Zhang J, Cui X, Teng Y, Zhang Y, Black M, Li Z, Shafer MM, Schauer JJ. The impact of household air cleaners on the oxidative potential of PM2.5 and the role of metals and sources associated with indoor and outdoor exposure. Environ Res. 2020 Feb;181:108919. doi: 10.1016/j.envres.2019.108919. Epub 2019 Nov 13. PubMed 31753466 ↗

Individual participant data

Plan to share: Undecided

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 23, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03282864
Collaborators
Underwriters Laboratory, Inc, Duke University, Tsinghua University, University of Wisconsin, Madison
Responsible party
Zhen Li (Attending Physician, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine) — Principal investigator
First posted
Sep 14, 2017
Start date
Jan 17, 2017
Primary completion
Apr 22, 2017
Completion
Dec 2020 (estimated)
Last update
Mar 23, 2020

Study contacts

Michael H. Bergin, PhD
study director · Duke University
Junfeng Zhang, PhD
principal investigator · Duke University
James J. Schauer, PhD
principal investigator · University of Wisconsin, Madison
Yinping Zhang, PhD
principal investigator · Tsinghua University
Feng Li, MD
principal investigator · Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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