Dataset Information

Blood Pressure Effect of Traffic-Related Air Pollution : A Crossover Trial of In-Vehicle Filtration.

ABSTRACT:

Background

Ambient air pollution, including traffic-related air pollution (TRAP), increases cardiovascular disease risk, possibly through vascular alterations. Limited information exists about in-vehicle TRAP exposure and vascular changes.

Objective

To determine via particle filtration the effect of on-roadway TRAP exposure on blood pressure and retinal vasculature.

Design

Randomized crossover trial. (ClinicalTrials.gov: NCT05454930).

Setting

In-vehicle scripted commutes driven through traffic in Seattle, Washington, during 2014 to 2016.

Participants

Normotensive persons aged 22 to 45 years (n = 16).

Intervention

On 2 days, on-road air was entrained into the vehicle. On another day, the vehicle was equipped with high-efficiency particulate air (HEPA) filtration. Participants were blinded to the exposure and were randomly assigned to the sequence.

Measurements

Fourteen 3-minute periods of blood pressure were recorded before, during, and up to 24 hours after a drive. Image-based central retinal arteriolar equivalents (CRAEs) were measured before and after. Brachial artery diameter and gene expression were also measured and will be reported separately.

Results

Mean age was 29.7 years, predrive systolic blood pressure was 122.7 mm Hg, predrive diastolic blood pressure was 70.8 mm Hg, and drive duration was 122.3 minutes (IQR, 4 minutes). Filtration reduced particle count by 86%. Among persons with complete data (n = 13), at 1 hour, mean diastolic blood pressure, adjusted for predrive levels, order, and carryover, was 4.7 mm Hg higher (95% CI, 0.9 to 8.4 mm Hg) for unfiltered drives compared with filtered drives, and mean adjusted systolic blood pressure was 4.5 mm Hg higher (CI, -1.2 to 10.2 mm Hg). At 24 hours, adjusted mean diastolic blood pressure (unfiltered) was 3.8 mm Hg higher (CI, 0.02 to 7.5 mm Hg) and adjusted mean systolic blood pressure was 1.1 mm Hg higher (CI, -4.6 to 6.8 mm Hg). Adjusted mean CRAE (unfiltered) was 2.7 μm wider (CI, -1.5 to 6.8 μm).

Limitations

Imprecise estimates due to small sample size; seasonal imbalance by exposure order.

Conclusion

Filtration of TRAP may mitigate its adverse effects on blood pressure rapidly and at 24 hours. Validation is required in larger samples and different settings.

Primary funding source

U.S. Environmental Protection Agency and National Institutes of Health.

SUBMITTER: Young MT

PROVIDER: S-EPMC11259360 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Blood Pressure Effect of Traffic-Related Air Pollution : A Crossover Trial of In-Vehicle Filtration.

Young Michael T MT Jansen Karen K Cosselman Kristen E KE Gould Timothy R TR Stewart James A JA Larson Timothy T Sack Coralynn C Vedal Sverre S Szpiro Adam A AA Kaufman Joel D JD

Annals of internal medicine 20231128 12

<h4>Background</h4>Ambient air pollution, including traffic-related air pollution (TRAP), increases cardiovascular disease risk, possibly through vascular alterations. Limited information exists about in-vehicle TRAP exposure and vascular changes.<h4>Objective</h4>To determine via particle filtration the effect of on-roadway TRAP exposure on blood pressure and retinal vasculature.<h4>Design</h4>Randomized crossover trial. (ClinicalTrials.gov: NCT05454930).<h4>Setting</h4>In-vehicle scripted comm ...[more]

PMID: 38011704

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Dataset Information

Blood Pressure Effect of Traffic-Related Air Pollution : A Crossover Trial of In-Vehicle Filtration.

Background

Objective

Design

Setting

Participants

Intervention

Measurements

Results

Limitations

Conclusion

Primary funding source

Publications

Blood Pressure Effect of Traffic-Related Air Pollution : A Crossover Trial of In-Vehicle Filtration.

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