Cardiovascular System, Respiratory System
Conditions
Keywords
Traffic-related pollution, Randomized controlled trial, Acute health effects
Brief summary
This study aims to assess the effects of acute exposure to traffic-related air pollution and the underlying mechanisms.
Detailed description
The investigators will conduct a randomized, crossover trial among 72 healthy young adults in Shanghai, China. The eligible participants will be randomly divided into 2 groups (36 volunteers per group). During the first stage, participants will be requested to take one walking task (from 13:00 to 17:30). The exposed group will walk along a busy road and be exposed to traffic-related air pollution, while the control group will walk in a traffic-free park. During the first 3 hours, all participants will rest for 30 minutes after each 15-minute walking. From 16:00, participants will stop walking and rest for 1.5 hours. Then both groups will enter a 2-week washout period. In the second stage, there will also be one walking task (from 13:00 to 17:30). The two groups will exchange their walking sites and repeat the previous trial. Physical examinations will be performed both before and after each walking task. Besides, we will ask volunteers to stay in school during the two days before walking. Health examinations include symptoms questionnaires, blood pressure tests, Holter monitoring, and spirometry. We plan to collect blood, urine, oropharyngeal swabs, and exhaled breath condensate before exposure, about one hour after exposure, and next morning.
Interventions
BEHAVIORALWalking along a busy road
The intervention group will walk along a busy road and be exposed to traffic-related air pollution for 4.5 hours (from 13:00 to 17:30), while alternating 15-minute walking and 30-minute rest periods.
BEHAVIORALWalking in a traffic-free park
The control group will walk in a traffic-free park for 4.5 hours (from 13:00 to 17:30), while alternating 15-minute walking and 30-minute rest periods.
Sponsors
Fudan University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Living in Shanghai during the study period; * Body mass index \> 18.5 and ≤ 28; * Non-smoking, no history of alcohol or drug abuse; * Completing the walking task we required.
Exclusion criteria
* Current or ever smokers; * Subjects with allergic disease, such as allergic rhinitis, allergic asthma, and atopy; * Subjects with cardiovascular disease, such as congenital heart disease, pulmonary heart disease, and hypertension; * Subjects with respiratory disease, such as asthma, chronic bronchitis, and chronic obstructive pulmonary disease; * Subjects wih chronic disease, such as diabetes, chronic hepatitis, and kidney disease; * Subjects with a history of major surgery; * Abnormal spirometry (FEV1 and FVC ≤ 75% of predicted and FEV1/FVC ≤ 0.65); * Medication use or dietary supplements intake in recent two months;
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in FEV1 | FEV1 will be examined before exposure, half an hour after exposure and 12 hours after exposure. | We plan to measure changes in forced expiratory volume in 1 second. |
| Blood Pressure | Blood pressure will be measured for 24 hours from 8:00 am on the morning of intervention to 8:00 am on the next morning. | We plan to measure systolic blood pressure (SBP) and diastolic blood pressure (DBP). |
| Heart Rate Variability Parameters | Volunteers will be asked to wear electrographic Holter monitors for 24 hours from 8:00 am on the morning of intervention to 8:00 am on the next morning. | We plan to measure heart rate variability (HRV) parameters. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes of FVC | 7:00 AM on the day of the walking session, half an hour after exposure and 12 hours after exposure (next morning) | Changes of forced vital capacity |
| Changes of FEV1/FVC | 7:00 AM on the day of the walking session, half an hour after exposure and 12 hours after exposure (next morning) | Changes of the ratio of forced expired volume in 1 second (FEV1) to forced vital capacity (FVC) |
| Changes of MMEF | 7:00 AM on the day of the walking session, half an hour after exposure and 12 hours after exposure (next morning) | Changes of maximal mid-expiratory flow |
Countries
China
Contacts
STUDY_DIRECTORHaidong Kan, PhD
Department of Environmental Health, School of Public Health, Fudan University
Outcome results
None listed