Cardiovascular Diseases
Conditions
Keywords
air pollution, traffic, vascular function, gasoline exhaust, diesel exhaust
Brief summary
The investigators will assess the vascular effects of riding in a car in heavily trafficked roadways, and whether filtering the car's air reduces those effects.
Detailed description
In this double-blind, crossover trial, randomized to order, recruited participants will be screened and then will accompany the study team on three typical commutes on separate days with sufficient washout (i.e., three weeks) between drives. One day this will occur with an effective filter system in the vehicle and the other two days without effective filtration; ineffective filtration is the most typical actual vehicle condition. Subjects will be unaware of the filtration conditions of the commute on that day. Each subject's experimental sessions will occur at the same time of day and will be separated by at least 21 days. The two sessions (either filtered air or traffic-derived entrained air) will be 120 minutes in duration and will encompass routes on heavily traveled roadways in the Seattle area. Before subjects begin the commute trials, they will go through the consent process and a series of screening tests. The study investigators will assess a series of measures regarding vascular function before and after each drive.
Interventions
OTHERFiltered Air
The vehicle is fitted with a (High-Efficiency Particulate Absorbing, HEPA) filter device incorporating a charcoal filter, as well as an augmented cabin filter
Sponsors
Environmental Protection Agency (EPA)
National Institute of Environmental Health Sciences (NIEHS)
University of Washington
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 49 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy
Exclusion criteria
* asthma, * high blood pressure, * diabetes, * high cholesterol, * other chronic conditions requiring ongoing medical care.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Gene Expression and DNA methylation | 30 minutes before 120 minute driving session; 30 minutes, 5 hour, and 24 hours post-driving session | analysis in circulating mononuclear cells; determined via fold change in abundance |
| Change in Brachial Artery Diameter from Pre-Drive to Post-Drive | 30 minutes before 120 minute driving session; 30 minutes post driving session | Ultrasound assessment of brachial artery diameter, in millimeters. |
| Change in Blood Pressure from Pre-Drive to During-Drive and Post-drive | 10 minutes before driving session; 15, 30, 45, 60, 75, 90, 100, 120 minutes following start of (120 minute) driving session; 10 minutes, 1.5 hours, 3.5 hours, 6 hours, 24 hours after end of driving session. | systolic and diastolic blood pressure measured in mmHg |
| Change in Retinal Arteriolar Diameter from Pre-Drive to Post-Drive | 30 minutes before 120 minute driving session; 30 minutes post driving session | measured by retinal photography, image analysis, in micrometers |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| circulating stress hormone | 30 minutes before 120 minute driving session; 5 hour and 24 hours post-driving session | cortisol by chemiluminescence (ng/mL) |
| complete blood count with differential | 30 minutes before 120 minute driving session; 5 hour and 24 hours post-driving session | laboratory values for hematologic indices (cells/uL) |
| inflammatory marker interleukin-6 | 30 minutes before 120 minute driving session; 5 hour and 24 hours post-driving session | interleukin-6 determined by chemiluminescence (pg/mL) |
| inflammatory marker c-reactive protein | 30 minutes before 120 minute driving session; 5 hour and 24 hours post-driving session | C-reactive protein by immunoturbidimetry (ug/mL) |
Countries
United States
Outcome results
None listed