Asthma and Indoor-air: Reducing Exposures (AIRE)

This study is currently recruiting participants. (see Contacts and Locations)
Verified January 2014 by University of California, Davis
Sponsor:
Information provided by (Responsible Party):
Deborah Bennett,PhD, University of California, Davis
ClinicalTrials.gov Identifier:
NCT01869543
First received: April 3, 2013
Last updated: January 13, 2014
Last verified: January 2014
  Purpose

Two hundred moderate to severely asthmatic children (6-12 years) will be enrolled in a study to look at the effectiveness of high efficiency filtration of indoor air in homes on reducing asthma symptoms. One intervention group will have high efficiency filters or filtration systems installed in their central heating and air conditioning (HVAC) system. The second intervention group will have high efficiency portable air cleaners placed in the child's bedroom and in the main living area. Each participant will receive true air filtration for a year and a placebo for a year. During the placebo period a sham filter will be used that removes very little of the particles. Measures of health effects will include days of symptoms, unplanned utilization of the healthcare system for asthma-related illness, short-term medication use, peak exhaled flow, spirometry, and exhaled nitric oxide (eNO).


Condition Intervention
Asthma
Other: Stand Alone Air Cleaner
Other: HVAC Modification

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver)
Official Title: Benefits of High Efficiency Filtration to Children With Asthma

Resource links provided by NLM:


Further study details as provided by University of California, Davis:

Primary Outcome Measures:
  • Days with asthma symptoms [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]

    The maximum number of days with symptoms, from a two-week recall period, will be determined every three months. The maximum number of days with symptoms will be defined as the largest value among the following three variables: (i) number of days with wheezing, tightness in the chest, or cough because of asthma, (ii) number of days that the child had to slow down or stop his/her play or activities because of asthma, wheezing or tightness in the chest, or cough, or (iii) number of nights that the child woke up because of asthma, wheezing or tightness in the chest, or cough.

    The seasonally adjusted mean difference in the number of symptom days between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.



Secondary Outcome Measures:
  • Forced expiratory volume at one second, percent predicted (FEV1 % predicted) [ Time Frame: Measured at 12 months and 24 months ] [ Designated as safety issue: No ]
    Lung function will be assessed using FEV1 % predicted. The adjusted mean difference in the FEV1% predicted between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Forced vital capacity, percent predicted (FVC % predicted) [ Time Frame: Measured at 12 months and 24 months ] [ Designated as safety issue: No ]
    Lung function will be assessed using FVC % predicted. The adjusted mean difference in the FVC% predicted between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Peak Expiratory Flow Rate (PEFR) [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]
    Lung function will be assessed using morning peak expiratory flow rate (PEFR), averaged for all days over one-week testing periods. The seasonally adjusted mean difference in the PERF measure between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Exhaled NO [ Time Frame: Measure at 6, 12, 18, and 24 months ] [ Designated as safety issue: No ]
    The seasonally adjusted mean difference in the Exhaled NO between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Days of missing school due to asthma [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]
    Days of missing school due to asthma will be expressed as a proportion of days of missing school versus the total number of school days during a two-week period. The seasonally adjusted mean difference in the proportion of missed school days between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Days of missing work for parents due to child's asthma [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]
    Days of missing work due to child's asthma will be expressed as a proportion of days of missing work versus the total number of work days during a two-week period. The seasonally adjusted mean difference in the proportion of missed work days between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Hospitalizations [ Time Frame: Count during 1-year true filtration period and count during 1-year sham filtration period ] [ Designated as safety issue: No ]
    The number of overnight hospitalizations due to asthma will be assessed every 3 months during real and sham periods. Participants will report number of overnight hospitalizations due to asthma that occurred in the previous three months. The adjusted mean hospitalization incidence ratio between the true and sham filtration periods will be compared using mixed-effects Poison regression models.

  • Emergency Room Visits [ Time Frame: Count during 1-year true filtration period and count during 1-year sham filtration period ] [ Designated as safety issue: No ]
    The number of emergency room visits due to asthma will be assessed every 3 months during real and sham periods. Participants will report number of emergency room visits due to asthma that occurred in the previous three months. The adjusted mean emergency room visit incidence ratio between the true and sham filtration periods will be compared using generalized mixed-effects regression models.

  • Unplanned Clinic Visits [ Time Frame: Count during 1-year true filtration period and count during 1-year sham filtration period ] [ Designated as safety issue: No ]
    The number of unplanned clinic visits due to asthma will be assessed every 3 months during real and sham periods. Participants will report number of unplanned clinic visits due to asthma that occurred in the previous three months. The adjusted mean unplanned clinic visit incidence ratio between the true and sham filtration periods will be compared using generalized mixed-effects regression models.

  • Unplanned Steroid treatments [ Time Frame: Count during 1-year true filtration period and count during 1-year sham filtration period ] [ Designated as safety issue: No ]
    The number of unplanned steroid treatments due to asthma will be assessed every 3 months during real and sham periods. Participants will report number of unplanned steroid treatments due to asthma that occurred in the previous three months. The adjusted mean unplanned steroid treatment incidence ratio between the true and sham filtration periods will be compared using generalized mixed-effects regression models.

  • Mini Pediatric Asthma Quality of Life Questionnaire (MiniPAQLQ) [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]
    The MiniPAQLQ has three composite domains, symptoms, emotional function, and activity limitation, each of which will be analyzed separately. The seasonally adjusted mean difference in each domain score between the true and sham filtration periods will be estimated using generalized linear mixed-effects regression models.

  • Allergy symptoms [ Time Frame: Measured at 3, 6, 9, 12, 15, 18, 21, and 24 months ] [ Designated as safety issue: No ]
    Allergy symptoms during two week recall periods will be summarized into a composite score. The seasonally adjusted mean difference in the scores between the true and sham filtration periods will be using generalized linear mixed-effects regression models.

  • Respiratory disease [ Time Frame: Count of incidents of respiratory disease during 1-year true filtration period and count during 1-year sham filtration period ] [ Designated as safety issue: No ]
    The number of incidents of respiratory disease will be assessed every 3 months during real and sham periods. Participants will report number of incidents of respiratory disease that occurred in the previous three months. The adjusted mean respiratory disease incidence ratio between the true and sham filtration periods will be compared using generalized mixed-effects regression models.


Estimated Enrollment: 200
Study Start Date: November 2013
Estimated Study Completion Date: July 2016
Estimated Primary Completion Date: July 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Stand Alone Air Cleaner-True/Sham
The participant will have stand alone air cleaners placed in their home. They will have true filtration followed by sham filtration.
Other: Stand Alone Air Cleaner
This is an environmental intervention using a stand alone air cleaner designed to reduce the air pollution levels in the home.
Experimental: Stand Alone Air Cleaner-Sham/True
Participants will have stand alone air cleaners placed in their homes. They will begin with sham filtration.
Other: Stand Alone Air Cleaner
This is an environmental intervention using a stand alone air cleaner designed to reduce the air pollution levels in the home.
Experimental: HVAC modification-True/Sham
Participants will have their HVAC system modified to include high efficiency filtration. They will begin true filtration followed by sham filtration.
Other: HVAC Modification
This is an environmental intervention that modifies the home HVAC system to include high efficiency air filtration designed to reduce the air pollution levels in the home.
Experimental: HVAC Modification-Sham/True
Participants will have their HVAC system modified to include high efficiency filtration. They will begin sham filtration.
Other: HVAC Modification
This is an environmental intervention that modifies the home HVAC system to include high efficiency air filtration designed to reduce the air pollution levels in the home.

  Eligibility

Ages Eligible for Study:   6 Years to 12 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • 6-12 years of age
  • Living in Fresno, San Bernardino or Riverside Counties.
  • Physician diagnosed asthma, as stated by the participant's caregiver.
  • In the last six months, the child must have had asthma symptoms at least twice a week for several weeks in a row.

Exclusion Criteria:

  • Children living in homes where more than 2 cigarettes are smoked per week in the home.
  • Children that spend 2 or more nights per week in another home.
  • Children living in homes that are planning on moving in the next 2 years.
  • Children living in homes that keep their windows open most of the time.
  • Children living in homes that have existing high efficiency filtration.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01869543

Contacts
Contact: Deborah Bennett, PhD 530-754-8282 dhbennett@ucdavis.edu
Contact: Rebecca Moran, MS 530-754-7379 rmoran@ucdavis.edu

Locations
United States, California
University of California, Davis- Department of Public Health Sciences Recruiting
Davis, California, United States, 95616
Contact: Deborah Bennett, PhD    530-754-8282    dhbennett@ucdavis.edu   
Principal Investigator: Deborah Bennett, PhD         
Sponsors and Collaborators
Deborah Bennett,PhD
Investigators
Principal Investigator: Deborah Bennett, PhD University of California, Davis
  More Information

No publications provided

Responsible Party: Deborah Bennett,PhD, Associate Professor, University of California, Davis
ClinicalTrials.gov Identifier: NCT01869543     History of Changes
Other Study ID Numbers: 346123, 11-324
Study First Received: April 3, 2013
Last Updated: January 13, 2014
Health Authority: United States: Institutional Review Board

Additional relevant MeSH terms:
Asthma
Bronchial Diseases
Respiratory Tract Diseases
Lung Diseases, Obstructive
Lung Diseases
Respiratory Hypersensitivity
Hypersensitivity, Immediate
Hypersensitivity
Immune System Diseases

ClinicalTrials.gov processed this record on July 26, 2014