Essential Hypertension
Conditions
Keywords
Traffic-related air pollution, Physical activity, Exercise, Blood pressure, Heart rate variability, Arterial stiffness, Microvascular responsiveness, Muscle oxygen saturation, Lung function
Brief summary
The investigators are investigating the effects of traffic-related air pollution (TRAP) on the cardiovascular and pulmonary response to exercise in patients with hypertension using a real world randomized, crossover study design. Participants will be exposed to 2 conditions: a low TRAP environment and a high TRAP environment. Each exposure will consist of 30 min of moderate-intensity exercise. Cardiovascular and pulmonary health outcomes will be measured before, during, and up to 24 hours following exposures. A minimum washout period of 1 week will be used to minimize carryover effects.
Interventions
BEHAVIORALExercise
Participants will engage in moderate-intensity (40-59% HRR) exercise for 30 min
Sponsors
University of British Columbia
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Crossover Assignment
Eligibility
Sex/Gender
ALL
Age
40 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
1. Age between 40-70 years of age 2. Previously diagnosed with elevated blood pressure or hypertension by a physician
Exclusion criteria
1. Current or ex-smokers (abstinent for less than one year) 2. Lives with an individual who currently smokes cigarettes, e-cigarettes (i.e., vaping), or cannabis 3. Hormone replacement therapy use 4. Currently on beta-blocker or angiotensin receptor blocker (ARB) therapy 5. Currently using over the counter drugs or supplements that may alter cardiovascular measures (as per the principal investigator's discretion) 6. Prior diagnosis of any other existing cardiovascular or pulmonary diseases and/or conditions (other than hypertension) 7. Musculoskeletal injury or lower limb limitation preventing safe engagement in moderate-intensity exercise
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline Blood Pressure at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | MAP, SBP, and DBP |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 24-Hour Blood Pressure | 24 hours post-exposure | MAP, SBP, and DBP |
| Heart Rate Variability | Baseline and up to 24 hours post-exposure | Indices of heart rate variability |
| Change from Baseline Arterial Stiffness at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | Pulse wave velocity and augmentation index |
| Change from Baseline Microvascular Responsiveness at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | Microvascular responsiveness (measured by near-infrared spectroscopy) |
| Severity of Symptoms | Baseline and 2 hours post-exposure | Severity of respiratory symptoms (e.g., dyspnea, cough, wheeze, chest tightness) and headache on a 0-5 scale |
| Change from Baseline FEV1 and FVC at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | Forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) measured by spirometry (in L) |
| Change from Baseline FEV1/FVC at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | FEV1/FVC ratio measured by spirometry |
| Change from Baseline FEF25-75 and PEFR at 2 Hours Post-Exposure | Baseline and 2 hours post-exposure | Forced expiratory flow at 25-75% of forced vital capacity (FEF25-75) and peak expiratory flow rate (PEFR) measured by spirometry (in L/s) |
| Muscle Oxygen Saturation | Continuously throughout the 30 minute exercise bouts (during exposure) | Muscle oxygen saturation (measured by near-infrared spectroscopy) |
Countries
Canada
Outcome results
None listed