Effects of Reducing Indoor Air Pollution on the Adult Asthmatic Response

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02153359

Acronym

INHALE 2

Enrollment

Registered

2014-06-03

Start date

2014-02-28

Completion date

2018-09-11

Last updated

2019-09-12

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

Conditions

Asthma

Keywords

asthma, HEPA, air pollutants, lung function, home environment, respiratory symptoms

Brief summary

This study is about asthma and how the environment affects asthma. Scientists know that air pollution (such as cigarette smoke and other particles in the air) can make asthma symptoms worse. This research is being done to study how the health of a person with asthma responds to an air cleaner. The investigator hypothesize that an air cleaner will improve the health of persons with asthma.

Detailed description

The investigators seek to determine the effect of placing air cleaner devices in the homes of adults with asthma on the adults' asthma health. To this end, the investigators aim to study 40 adults with asthma that are 18-50 years of age and live in Baltimore. Participants will receive either true air cleaners or sham cleaners in a blinded, randomized manner for one month, and then, after a washout period, participants will cross over and receive the other intervention (sham or true cleaner). All participants will have environmental monitoring (personal and in-home) to determine participants' particulate matter exposure, and be followed repeatedly during the 3 month study period for markers of asthma disease, including respiratory symptoms, medication and health care utilization, pulmonary function, systemic markers of inflammation, and bronchoscopic evidence of airway inflammation or epithelial cell dysfunction.

Interventions

DEVICEHigh Efficiency Particulate Air Cleaner

DEVICESham air cleaner

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

SUPPORTIVE_CARE

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 50 Years

Healthy volunteers

Inclusion criteria

* Age 18-50 years of age * Non-smoker (\<100 cigarettes in lifetime) * Physician diagnosis of asthma * Symptoms of asthma and/or reliever medication use in the past 6 months * Living in the current residence \>= 6 months within Baltimore * Enrollment in, and completion of, the observational environmental asthma study Inhale 1

Exclusion criteria

* Current diagnosis of another major pulmonary disease, other significant morbidity * Pregnancy (as defined by a positive urine pregnancy test at screening of all women of child-bearing potential) * Planning to relocate residence or activity that necessitates travel away from home for prolonged period of time during the study period * Current use of an air cleaner in the home

Design outcomes

Primary

Measure	Time frame	Description
PM2.5 Concentration (ug/m^3)	Approximately 1 month	Fine particulate matter (PM2.5) concentration as assessed by a passive filter placed in the participant's home.
PM2.5-10 Concentration (ug/m^3)	Approximately 1 month	Coarse particulate matter (PM2.5-10) concentration as assessed by a passive filter placed in the participant's home.

Secondary

Measure	Time frame	Description
Number of Days With Activity Limitations	7 days	Number of reported days with activity limitations due to asthma symptoms.
Number of Nights Disrupted by Asthma Symptoms	7 nights	The number of nights spent sleeping that was disrupted due to asthma symptoms.
Number of Days of School/Work Missed Due to Asthma Symptoms	7 days	The number of days of school or work missed due to asthma symptoms.
Number of Days of Unscheduled Visits to the Doctor Due to Asthma Symptoms	7 days	The number of days of unscheduled, urgent visits to the office, urgent care or emergency department due to asthma symptoms.
Asthma Disease Status as Assessed by the Asthma Control and Communication Instrument (ACCI)	Approximately 1 month	The ACCI is a validated clinical tool that measures asthma disease status during routine health care and is valid for use in both black and white populations. The sum of each of the 5 ACCI asthma control domains results in a final ACCI score ranging from 0 (better control) to 19 (worse control).
FEV1 Percentage of FVC	1 day	The pre-bronchodilator forced expiratory volume in 1 second over the forced vital capacity as assessed by spirometry.
Air Nicotine Concentration (ug/m^3)	Approximately 1 month	Indoor air nicotine concentration as assessed by a passive filter placed in the participant's home.
Bronchoalveolar Lavage Differential Neutrophil Count	1 Day	The percentage of neutrophils in the bronchoalveolar lavage cell count.
Bronchoalveolar Lavage Differential Eosinophil Count	1 day	The eosinophil percentage in the bronchoalveolar lavage cell count differential.
Pre-bronchodilator Forced Vital Capacity (Litres)	1 day	Pre-bronchodilator forced vital capacity (FVC) as assessed with spirometry
Pre-bronchodilator Forced Expiratory Volume in 1 Second (Litres)	1 day	The pre-bronchodilator forced expiratory volume in 1 second (FEV1) as assessed by spirometry.
Asthma-specific Health-related Quality of Life as Assessed by the Asthma Quality of Life Questionnaire (AQLQ)	Approximately 1 month	The AQLQ is validated clinical tool to assess asthma-specific health-related quality of life instrument that taps both physical and emotional impact of disease. Scores range from 1-7, with higher scores indicating better quality of life.
Number of Symptom-free Days	7 days	The number of reported days without daytime asthma symptoms (symptom-free days) as based on daily symptom diaries recorded by the patient.

Countries

United States

Participant flow

Participants by arm

Arm	Count
All Participants A High Efficiency Particulate Air Cleaner (HEPA) intervention (experimental arm) or sham air cleaner (sham comparator) will be placed in the participant's home for one month. During the last week of the month, health assessments will be conducted, which include in-home health questionnaires, symptom-, and activity- diaries/recalls, blood, and hand-held spirometry. Participants will also be asked to wear a light backpack with air monitoring devices during the course of the day during the last week in order to measure participants' exposures to pollutants. Finally, at the end of the month, participants will be asked to report to the Johns Hopkins outpatient endoscopy suite for bronchoscopy, during which airway sampling will occur under conscious sedation. After this one month intervention period, participants will then enter a wash-out period where no intervention or outcome measures are undertaken for at least one month prior to cross-over to the other arm.	23
Total	23

Arm

Count

All Participants

A High Efficiency Particulate Air Cleaner (HEPA) intervention (experimental arm) or sham air cleaner (sham comparator) will be placed in the participant's home for one month. During the last week of the month, health assessments will be conducted, which include in-home health questionnaires, symptom-, and activity- diaries/recalls, blood, and hand-held spirometry. Participants will also be asked to wear a light backpack with air monitoring devices during the course of the day during the last week in order to measure participants' exposures to pollutants. Finally, at the end of the month, participants will be asked to report to the Johns Hopkins outpatient endoscopy suite for bronchoscopy, during which airway sampling will occur under conscious sedation. After this one month intervention period, participants will then enter a wash-out period where no intervention or outcome measures are undertaken for at least one month prior to cross-over to the other arm.

Total

Withdrawals & dropouts

Period	Reason	FG000	FG001
Intervention 2 (1 Month)	Lost to Follow-up	0	2

Baseline characteristics

Characteristic	All Participants
Age, Continuous	39 years STANDARD_DEVIATION 8.8
Annual household income <$25,000	13 Participants
Annual household income $25,000-$50,000	6 Participants
Annual household income >$50,000	2 Participants
Annual household income Unreported	2 Participants
Asthma medication use Albuterol only	13 participants
Asthma medication use Inhaled corticosteroid	8 participants
Asthma medication use Leukotriene modifier	3 participants
Asthma medication use Oral corticosteroids	1 participants
Asthma severity Mild intermittent	6 Participants
Asthma severity Mild persistent	4 Participants
Asthma severity Moderate persistent	11 Participants
Asthma severity Severe persistent	2 Participants
At least 1 emergency department visit for asthma in last year No	16 Participants
At least 1 emergency department visit for asthma in last year Yes	7 Participants
Atopic status Atopic	20 Participants
Atopic status Not atopic	3 Participants
Body mass index	40.4 kg/m^2 STANDARD_DEVIATION 8.4
Education At least some college	9 Participants
Education High school graduate	11 Participants
Education Not high school graduate	3 Participants
General condition of home 1 - Extremely poor: no evidence of cleaning	1 Participants
General condition of home 2 - Poor: minimal cleaning	2 Participants
General condition of home 3 - Average: some cleaning	8 Participants
General condition of home 4 - Above average: clean without much clutter	6 Participants
General condition of home 5 - Excellent: very clean, organized	2 Participants
Health insurance Other	1 Participants
Health insurance Private	8 Participants
Health insurance Public	14 Participants
Lung function Pre-bronchodilator FEV1/FVC	74 percentage STANDARD_DEVIATION 9
Lung function Pre-bronchodilator FEV1 % predicted	92.7 percentage STANDARD_DEVIATION 26.9
Lung function Pre-bronchodilator FVC % predicted	102.6 percentage STANDARD_DEVIATION 27.7
Presence of detectable indoor air nicotine concentration	0.58 ug/m^3 STANDARD_DEVIATION 1.08
Race/Ethnicity, Customized African American	18 Participants
Race/Ethnicity, Customized Non-African American	5 Participants
Sex: Female, Male Female	19 Participants
Sex: Female, Male Male	4 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk
deaths Total, all-cause mortality	0 / 23	0 / 23
other Total, other adverse events	0 / 23	0 / 23
serious Total, serious adverse events	0 / 23	0 / 23

Outcome results

Primary

PM2.5-10 Concentration (ug/m^3)

Coarse particulate matter (PM2.5-10) concentration as assessed by a passive filter placed in the participant's home.