Intervention Study on the Health Impact of Air Filters in Chinese Adults

Cardiopulmonary Benefits of Reducing Indoor Particles of Outdoor Origin: a Randomized Double-blind Crossover Trial of Air Purifiers

This study aimed to evaluate whether a short-term indoor air purifier intervention improves cardiopulmonary health based on a randomized double-blind crossover trial

We conducted a randomized double-blind crossover trial among 35 healthy college students in Shanghai, China in 2014. These students lived in dormitories that were randomized into two groups and alternated the use of true or sham air purifiers for 48 hours with a 2-week wash-out interval.All participants and research staff were blinded to the group assignment. We requested all participants to stay in their dormitory room with the windows/doors closed throughout each 48-hour intervention period. We delivered foods and drinks to each room during the intervention period. All interventions started at 8 a.m. to avoid issues related to diurnal variation. We evaluated health endpoints and drew blood immediately after the completion of each 48-hour intervention. We measured 14 circulating biomarkers of inflammation, coagulation and vasoconstriction, lung function, blood pressure (BP), and fractional exhaled nitric oxide (FeNO).

Inclusion Criteria:

• Healthy college students aged between 18 and 26
• All the subjects should stay indoor almost the entire time, and stayed within the central urban area of shanghai during the wash-out period.

Exclusion Criteria:

• current smokers or ever smokers
• chronic respiratory diseases
• chronic cardiovascular diseases
• acute infections
• medication use in recent one month