Indoor Air and Children Health Study

Study Overview
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Brief Summary
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The objective of this study is to investigate the cardiopulmonary health effects of indoor air purification and different indoor environmental factors among school students in Beijing.

Detailed Description
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This randomized, double-blind crossover study was conducted to explore the cardiopulmonary effects of ionization air purification among 48 children in Beijing. Real or sham purification was performed in classrooms for 5 weekdays in a random order with a 2-month wash-out period. During the study periods, different indoor environmental factors were monitored including size-fractionated particulate matter (PM), black carbon (BC), ozone, carbon dioxide (CO2), negative air ions (NAI), noise, temperature and relative humidity, which were controlled as confounders in the analysis of the effects of indoor air purification. In addition, we analyzed the cardiopulmonary effects of those environmental factors on the children.

Official Title
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Cardiopulmonary Health Effects of Indoor Air Purification and Different Indoor Environmental Factors Among School Children in Beijing

Conditions
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Cardiopulmonary Disease

Intervention / Treatment
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* Other: Air purifier


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: living in Beijing for more than two consecutive years; living in school dormitories from Monday to Friday. Exclusion Criteria: suffering any health condition; having asthma or thoracic surgery history.

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Real purification<br>Air purifier turned on | Other: Air purifier<br>* active- or sham-mode air purifier used in 6 classrooms in a school with a crossover design<br>|
| Sham Comparator: Sham purification<br>Air purifier turned off | Other: Air purifier<br>* active- or sham-mode air purifier used in 6 classrooms in a school with a crossover design<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Levels of lung function indicators | Lung function test was conducted including forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF). | 10 weekdays for intervention (active or sham) and 2 wash-out months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in autonomic cardiac function | Ambulatory electrocardiogram (ECG) was monitored including heart rate (HR) and heart rate variability (HRV). | 10 weekdays for intervention (active or sham) and 2 wash-out months | 
| Level of respiratory inflammation | Fractional exhaled nitric oxide (FeNO) test was conducted. | 10 weekdays for intervention (active or sham) and 2 wash-out months | 
| Changes in ST-segment elevation | Ambulatory electrocardiogram (ECG) was monitored. | 10 weekdays for intervention (active or sham) and 2 wash-out months | 
| Levels of oxidative stress in Exhaled Breath Condensate (EBC) | EBC was collected using a designated device for oxidative stress analysis. | 10 weekdays for intervention (active or sham) and 2 wash-out months | 
| Levels of urinary metabolomics | Urine samples were collected for metabolomics analysis. | 10 weekdays for intervention (active or sham) and 2 wash-out months |