Health Effects of Indoor Air Filtration in Healthy Chinese Adults

• Sponsor: Fudan University (Other)
• Overall Status: Completed
• CT.gov ID: NCT02712333
• Collaborator: (none)
• Enrollment: 60
• Location: 1
• Arms: 2
• Duration (Months): 7
• Patients Per Site Per Month: 8.6

Study Details

Study Description

Brief Summary

This study aims to detect serum metabolite changes, as well as other health indicators with the intervention of air purifiers on a randomized, crossover, double-blind trial.

Condition or Disease	Intervention/Treatment	Phase
Blood Pressure	Behavioral: Air Purifiers; Behavioral: Sham Air Purifiers	N/A

Detailed Description

The investigators conducted a randomized double-blind crossover trial among 60 healthy college students in Shanghai, China from November to December, 2015. These students lived in dormitories that were randomized into two groups and alternated the use of true or sham air purifiers for 9 consecutive days with a 2-week wash-out interval. All participants and research staffs were blinded to the group assignment. All participants were required to stay in their dormitory with the windows/doors closed for at least 50% of the time on weekdays and for 80% on weekends throughout the 9-day intervention period. All interventions started at 7 a.m. to avoid issues related to diurnal variation. Health endpoints, including blood pressure, fractional exhaled nitric oxide were evaluated and biological samples such as morning urine, fast blood and buccal cells were collected at baseline and immediately after the completion of each intervention period.

Study Design

• Study Type: Interventional
• Actual Enrollment: 60 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: Double (Participant, Investigator)
• Primary Purpose: Prevention
• Official Title: Health Effects of Indoor Air Filtration in Healthy Chinese Adults: An Intervention Study
• Study Start Date: Nov 1, 2015
• Actual Primary Completion Date: Dec 1, 2015
• Actual Study Completion Date: Jun 1, 2016

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Air purifiers Participants in this group received an intervention of true air purifiers placed in the center of the room.	Behavioral: Air Purifiers; The 17 dormitory rooms and their residents were randomized into two groups: the intervention and control group. The intervention group went through a 9-day intervention with an air purifier placed in the center of the room. All rooms in this group used the same qualified air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms with the windows/doors closed throughout intervention period. All participants and research staffs were blinded to the group assignment.
Sham Comparator: Control Participants in this group received an intervention of sham air purifiers, which were under the same conditions as the true purifiers except the filter gauze in them were removed.	Behavioral: Sham Air Purifiers; The control group went through a 9-day intervention with a sham air purifier (with its filter gauze removed) placed in the center of the room. All rooms used the same air purifiers (model KJEA200e, 3M) as the intervention group, except the filter gauze was removed. During the study period all participants were required to stay in their dormitory rooms with the windows/doors closed. All participants and research staffs were blinded to the group assignment.

Outcome Measures

Primary Outcome Measures

1. Changes of Serum Cortisol Levels [at the end of each 9-day intervention period]

   Using metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisol with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)

2. Changes of Serum Cortisone Concentration [at the end of each 9-day intervention period]

   Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisone with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)

3. Changes of Serum Epinephrine Concentrations [at the end of each 9-day intervention]

   Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of epinephrine with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)

4. Changes of Serum Norepinephrine Concentration [at the end of each 9-day intervention]

   Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisol with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)

Secondary Outcome Measures

1. Systolic Blood Pressure [at the end of each 9-day intervention period]

   To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).

2. Diastolic Blood Pressure [at the end of each 9-day intervention]

   To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).

3. Pulse Pressure [at the end of each 9-day intervention]

   To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 30 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Healthy university students in Jiangwan Campus, Fudan university

• Non-smoking, no history of alcohol or drug abuse

• Free of chronic cardiovascular, respiratory, liver and kidney disease

• Spend at least 50% (weekdays) or 80% (weekends) of time indoors

Exclusion Criteria:

• Current or ever smokers

• History of asthma, chronic bronchitis，cough, hypertension or other chronic inflammatory disease

• acute infections

• medication use in recent one month

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Department of Environmental Health, School of Public Health, Fudan University	Shanghai	Shanghai	China	200032

Sponsors and Collaborators

• Fudan University

Investigators

• Study Director: Haidong Kan, Ph.D., School of Public Health，Fudan University

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Haidong Kan, Professor, Fudan University
• ClinicalTrials.gov Identifier: NCT02712333
• Other Study ID Numbers: FDEH-AF2015
• First Posted: Mar 18, 2016
• Last Update Posted: Oct 2, 2017
• Last Verified: May 1, 2017

• Individual Participant Data (IPD) Sharing Statement: Undecided
• Plan to Share IPD: Undecided
• Keywords provided by Haidong Kan, Professor, Fudan University: PM2.5; air purification; randomized controlled trial; metabolomics; Metabolites; exhaled nitric oxide

Study Results

Participant Flow

Recruitment Details	Recruitment was conducted on November, 2015 in Jiangwan Campus, Fudan University. A total of 65 participants were assessed for eligibility and 60 of them were finally recruited

Arm/Group Title	Group 1-air Purification First, Then Sham Air Purification	Group2-sham Air Purification First, Then Real Air Purification
Arm/Group Description	Participants in this group received an intervention of true air purifiers placed in the center of the room. Real Air Purification: The 17 dormitory rooms and their residents were randomized into two groups: the intervention and control group. The intervention group went through a 9-day intervention with an air purifier placed in the center of the room. All rooms in this group used the same qualified air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms as much as possible with the windows/doors closed throughout intervention period. All participants and research staffs were blinded to the group assignment.	Participants in this group received an intervention of sham air purifiers, which were under the same conditions as the true purifiers except the filter gauze in them were removed. Sham Air Purification: This group went through a 9-day intervention with a sham air purifier (with its filter gauze removed) placed in the center of the room. All rooms used the same air purifiers (model KJEA200e, 3M) as the intervention group, except the filter gauze was removed. During the study period all participants were required to stay in their dormitory rooms as much as possible with the windows/doors closed. All participants and research staffs were blinded to the group assignment.
Period Title: First Period
STARTED	34	26
COMPLETED	31	24
NOT COMPLETED	3	2
Period Title: First Period
STARTED	31	24
COMPLETED	31	24
NOT COMPLETED	0	0

Baseline Characteristics

Arm/Group Title	Group1-air Purification First, Then Sham Air Purification	Group2-sham Air Purification First, Then Real Air Purification	Total
Arm/Group Description	Participants in this group received a treatment of true air purification first, and then switched to the sham purification treatment the second stage. For real air purification, we used high efficient air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms with the windows/doors closed throughout intervention period. For sham air purification, we placed a sham air purifier (with HEPA filters removed) while keeping the rest of the experiment conditions and requirements for the participants unchanged. All participants and research staffs were blinded to the group assignment.	Participants in this group received a treatment of sham air purification first, and then switched to the real purification treatment the second stage. For real air purification, we used high efficient air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms with the windows/doors closed throughout intervention period. For sham air purification, we placed a sham air purifier (with HEPA filters removed) while keeping the rest of the experiment conditions and requirements for the participants unchanged. All participants and research staffs were blinded to the group assignment.	Total of all reporting groups
Overall Participants	31	24	55
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	20.0 (1.3)	20.6 (1.4)	20.2 (1.3)
Sex: Female, Male (Count of Participants)
Female	17 54.8%	11 45.8%	28 50.9%
Male	14 45.2%	13 54.2%	27 49.1%
Body mass index (kg/m^2) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [kg/m^2]	21.6 (2.9)	20.6 (2.5)	21.1 (2.6)

Outcome Measures

1. Primary Outcome

Title	Changes of Serum Cortisol Levels
Description	Using metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisol with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)
Time Frame	at the end of each 9-day intervention period

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Purification
Arm/Group Description	Participants in this group received a treatment of air purification.	Participants received sham air purification first.
Measure Participants	55	55
Mean (Standard Deviation) [relative intensity]	0.012835 (0.00371)	0.016206 (0.00474)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum cortisol levels (presented as relative intensities in high perfomance liquid chromatography-mass spectrum) by treatments (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.05
	Comments	the p-value has been adjusted for multiple comparisons
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	7.53
	Confidence Interval	(2-Sided) 95%; 4.65 to 10.41
	Parameter Dispersion	Type: Value:
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments
	Method	t-test, 2 sided
	Comments
Method of Estimation	Estimation Parameter	fold change
	Estimated Value	1.33
	Confidence Interval	(2-Sided) %; to
	Parameter Dispersion	Type: Value:
	Estimation Comments	fold change is calculated by measurments from the sham purification group/measurements from the real purification group

2. Primary Outcome

Title	Changes of Serum Cortisone Concentration
Description	Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisone with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)
Time Frame	at the end of each 9-day intervention period

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Purification
Arm/Group Description	Participants received a treatment of air purification	Participants received a treatment of sham air purification
Measure Participants	55	55
Mean (Standard Error) [relative intensity]	0.021076 (0.004375)	0.024338 (0.004625)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum cortisone levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments	the p-value has been adjusted for multiple comparisons.
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	3.69
	Confidence Interval	(2-Sided) 95%; 1.85 to 5.54
	Parameter Dispersion	Type: Value:
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments
	Method	t-test, 2 sided
	Comments
Method of Estimation	Estimation Parameter	fold change
	Estimated Value	1.18
	Confidence Interval	(2-Sided) %; to
	Parameter Dispersion	Type: Value:
	Estimation Comments	fold change is calculated by measurments from the sham purification group/measurements from the real purification group

3. Primary Outcome

Title	Changes of Serum Epinephrine Concentrations
Description	Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of epinephrine with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)
Time Frame	at the end of each 9-day intervention

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Air Purification
Arm/Group Description	Participants received a treatment of real air purification.	Participants received a treatment of sham air purification.
Measure Participants	55	55
Mean (Standard Error) [relative intensity]	0.140609 (0.027514)	0.165321 (0.036633)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum epinephrine levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments	the p-value has been adjusted for multiple comparisons.
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	5.17
	Confidence Interval	(2-Sided) 95%; 3.21 to 7.14
	Parameter Dispersion	Type: Value:
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments
	Method	t-test, 2 sided
	Comments
Method of Estimation	Estimation Parameter	fold change
	Estimated Value	1.20
	Confidence Interval	(2-Sided) %; to
	Parameter Dispersion	Type: Value:
	Estimation Comments	fold change is calculated by measurments from the sham purification group/measurements from the real purification group

4. Primary Outcome

Title	Changes of Serum Norepinephrine Concentration
Description	Use metabolomic methods to screen and quantify all the serum metabolites, and calculate changes in main metabolites in sham purification compared to real purification. Relative intensity was calculated by dividing the peak intensity of cortisol with the peak intensity of internal standard (2-chloro-D-phenylalanine methanol solution, 0.014mg/mL)
Time Frame	at the end of each 9-day intervention

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Purification
Arm/Group Description	Participants received a treatment of air purification	Participants received a treatment of sham air purification
Measure Participants	55	55
Mean (Standard Deviation) [relative intensity]	0.030752 (0.024335)	0.038695 (0.024624)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum norepinephrine levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments	the p-value has been adjusted for multiple comparisons
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	11.28
	Confidence Interval	(2-Sided) 95%; 7.37 to 15.21
	Parameter Dispersion	Type: Value:
	Estimation Comments

Statistical Analysis 2

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments
	Method	t-test, 2 sided
	Comments
Method of Estimation	Estimation Parameter	fold change
	Estimated Value	1.57
	Confidence Interval	(2-Sided) %; to
	Parameter Dispersion	Type: Value:
	Estimation Comments	fold change is calculated by measurments from the sham purification group/measurements from the real purification group

5. Secondary Outcome

Title	Systolic Blood Pressure
Description	To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).
Time Frame	at the end of each 9-day intervention period

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Purification
Arm/Group Description	Participants received a treatment of air purification	Participants received a treatment of sham air purification
Measure Participants	55	55
Mean (Standard Deviation) [mmHg]	102.2 (13.4)	104.8 (12.8)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum SBP levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	<0.01
	Comments
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	0.84
	Confidence Interval	(2-Sided) 95%; 0.09 to 1.59
	Parameter Dispersion	Type: Value:
	Estimation Comments

6. Secondary Outcome

Title	Diastolic Blood Pressure
Description	To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).
Time Frame	at the end of each 9-day intervention

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Air Purification
Arm/Group Description	Participants received a treatment of air purification	Participants received a treatment of sham air purification
Measure Participants	55	55
Mean (Standard Deviation) [mmHg]	64.5 (9.6)	65.2 (8.8)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum cortisol levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	>0.05
	Comments
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	0.31
	Confidence Interval	(2-Sided) 95%; -1.59 to 0.96
	Parameter Dispersion	Type: Value:
	Estimation Comments

7. Secondary Outcome

Title	Pulse Pressure
Description	To eliminate possible error, blood pressure for each participant were conducted by the same working staff using the same instrument. Average levels were calculated by treatments (intervention or control).
Time Frame	at the end of each 9-day intervention

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Real Purification	Sham Air Purification
Arm/Group Description	Participants received a treatment of air purification	Participants received a treatment of sham air purification
Measure Participants	55	55
Mean (Standard Deviation) [mmHg]	37.7 (7.5)	39.6 (8.3)

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Real Purification, Sham Purification
	Comments	we analyzed the serum cortisol levels by treatment (intervention group vs control group)
	Type of Statistical Test	Superiority or Other
	Comments
Statistical Test of Hypothesis	p-Value	>0.05
	Comments
	Method	Mixed Models Analysis
	Comments
Method of Estimation	Estimation Parameter	% increase per 10μg/m3 increase of PM2.5
	Estimated Value	1.24
	Confidence Interval	(2-Sided) 95%; -1.14 to 3.63
	Parameter Dispersion	Type: Value:
	Estimation Comments

Adverse Events

Arm/Group Title	Real Air Purification		Sham Air Purification
Arm/Group Description	Participants in this group received an intervention of true air purifiers placed in the center of the room. Real Air Purification: The 17 dormitory rooms and their residents were randomized into two groups: the intervention and control group. The intervention group went through a 9-day intervention with an air purifier placed in the center of the room. All rooms in this group used the same qualified air purifiers (model KJEA200e, 3M), and all participants were required to stay in their dormitory rooms as much as possible with the windows/doors closed throughout intervention period. All participants and research staffs were blinded to the group assignment.		Participants in this group received an intervention of sham air purifiers, which were under the same conditions as the true purifiers except the filter gauze in them were removed. Sham Air Purification: This group went through a 9-day intervention with a sham air purifier (with its filter gauze removed) placed in the center of the room. All rooms used the same air purifiers (model KJEA200e, 3M) as the intervention group, except the filter gauze was removed. During the study period all participants were required to stay in their dormitory rooms as much as possible with the windows/doors closed. All participants and research staffs were blinded to the group assignment.
All Cause Mortality
	Real Air Purification		Sham Air Purification
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	/ (NaN)		/ (NaN)
Serious Adverse Events
	Real Air Purification		Sham Air Purification
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/55 (0%)		0/55 (0%)
Other (Not Including Serious) Adverse Events
	Real Air Purification		Sham Air Purification
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/55 (0%)		0/55 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.