Health Effects of Indoor Air Filtration in Healthy Chinese Adults

Not Applicable

Completed

Conditions: Blood Pressure

Interventions: Behavioral: Air Purifiers
Behavioral: Sham Air Purifiers

Registration Number: NCT02712333

Lead Sponsor: Fudan University

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.

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.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 60

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

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Air purifiers	Air Purifiers	Participants in this group received an intervention of true air purifiers placed in the center of the room.
Control	Sham Air Purifiers	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.

Primary Outcome Measures

Name	Time	Method
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)
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)
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)
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

Name	Time	Method
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).
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).
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).