Trial Outcomes & Findings for Reducing Traffic Pollution Exposure Improves Blood Pressure (NCT NCT04029129)
NCT ID: NCT04029129
Last Updated: 2023-09-28
Results Overview
Systolic blood pressure measured with ambulatory blood pressure monitors in mmHg.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
77 participants
Primary outcome timeframe
Over 2 hour exposure period, we measured SBP after 20 minutes with the objective to assess change in SBP in a time series of measurements over that time period.
Results posted on
2023-09-28
Participant Flow
Using a 3-period crossover design, 77 participants were randomized to attend. Three 2-hour-long exposure sessions separated by 1-week washout periods. None was excluded.
Participant milestones
| Measure |
High Exposure (First Session) Low, Medium
Ambient air was allowed freely into the room.
|
Medium Exposure (First Session) High, Low Exposure
Limited air filtration was used to partially reduce levels of pollution in the room relative to outside.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
Low Exposure (First Session) Medium, High Exposure
Doors and windows were closed and sealed and full filtration was used to maximally reduce pollution in the room.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
|---|---|---|---|
|
First Intervention (2 Hours)
STARTED
|
30
|
28
|
19
|
|
First Intervention (2 Hours)
COMPLETED
|
30
|
28
|
19
|
|
First Intervention (2 Hours)
NOT COMPLETED
|
0
|
0
|
0
|
|
Wash Out (1 Week)
STARTED
|
30
|
28
|
19
|
|
Wash Out (1 Week)
COMPLETED
|
30
|
28
|
19
|
|
Wash Out (1 Week)
NOT COMPLETED
|
0
|
0
|
0
|
|
Third Intervention (2 Hours)
STARTED
|
30
|
28
|
19
|
|
Third Intervention (2 Hours)
COMPLETED
|
30
|
28
|
19
|
|
Third Intervention (2 Hours)
NOT COMPLETED
|
0
|
0
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Reducing Traffic Pollution Exposure Improves Blood Pressure
Baseline characteristics by cohort
| Measure |
High Exposure (First Session), Low, Medium Exposure
n=30 Participants
Ambient air was allowed freely into the room. Participants first received a 2-hour-long High exposure session. After a washout period of 1 week, they then received a 2-hour-long Low exposure session. After a washout period of 1 week, they then received a 2-hour-long Medium exposure session. All sessions occurred on the same day of the week.
|
Medium Exposure(First Session), High, Low Exposure
n=28 Participants
Limited air filtration was used to partially reduce levels of pollution in the room relative to outside.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
Participants first received a 2-hour-long Medium exposure session. After a washout period of 1 week, they then received a 2-hour-long High exposure session. After a washout period of 1 week, they then received a 2-hour-long Low exposure session. All sessions occurred on the same day of the week.
|
Low Exposure (First Session), Medium, High Exposure
n=19 Participants
Doors and windows were closed and sealed and full filtration was used to maximally reduce pollution in the room.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
Participants first received a 2-hour-long Low exposure session. After a washout period of 1 week, they then received a 2-hour-long Medium exposure session. After a washout period of 1 week, they then received a 2-hour-long High exposure session. All sessions occurred on the same day of the week.
|
Total
n=77 Participants
Total of all reporting groups
|
|---|---|---|---|---|
|
Age, Continuous
|
59.7 years
STANDARD_DEVIATION 10.5 • n=99 Participants
|
63.3 years
STANDARD_DEVIATION 9.6 • n=107 Participants
|
59.7 years
STANDARD_DEVIATION 10.5 • n=206 Participants
|
59.7 years
STANDARD_DEVIATION 10.5 • n=7 Participants
|
|
Sex: Female, Male
Female
|
27 Participants
n=99 Participants
|
22 Participants
n=107 Participants
|
12 Participants
n=206 Participants
|
61 Participants
n=7 Participants
|
|
Sex: Female, Male
Male
|
3 Participants
n=99 Participants
|
6 Participants
n=107 Participants
|
7 Participants
n=206 Participants
|
16 Participants
n=7 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
1 Participants
n=99 Participants
|
2 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
3 Participants
n=7 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
29 Participants
n=99 Participants
|
26 Participants
n=107 Participants
|
19 Participants
n=206 Participants
|
74 Participants
n=7 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
0 Participants
n=7 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
0 Participants
n=7 Participants
|
|
Race (NIH/OMB)
Asian
|
23 Participants
n=99 Participants
|
21 Participants
n=107 Participants
|
15 Participants
n=206 Participants
|
59 Participants
n=7 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
0 Participants
n=7 Participants
|
|
Race (NIH/OMB)
Black or African American
|
1 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
1 Participants
n=206 Participants
|
2 Participants
n=7 Participants
|
|
Race (NIH/OMB)
White
|
6 Participants
n=99 Participants
|
6 Participants
n=107 Participants
|
3 Participants
n=206 Participants
|
15 Participants
n=7 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=99 Participants
|
0 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
0 Participants
n=7 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=99 Participants
|
1 Participants
n=107 Participants
|
0 Participants
n=206 Participants
|
1 Participants
n=7 Participants
|
|
Region of Enrollment
United States
|
30 Participants
n=99 Participants
|
28 Participants
n=107 Participants
|
19 Participants
n=206 Participants
|
77 Participants
n=7 Participants
|
|
Systolic Blood Pressure
|
115.9 mmHg
STANDARD_DEVIATION 14.4 • n=99 Participants
|
118.6 mmHg
STANDARD_DEVIATION 17.6 • n=107 Participants
|
120.3 mmHg
STANDARD_DEVIATION 23.4 • n=206 Participants
|
118.0 mmHg
STANDARD_DEVIATION 17.9 • n=7 Participants
|
PRIMARY outcome
Timeframe: Over 2 hour exposure period, we measured SBP after 20 minutes with the objective to assess change in SBP in a time series of measurements over that time period.Systolic blood pressure measured with ambulatory blood pressure monitors in mmHg.
Outcome measures
| Measure |
High Exposure
n=77 Participants
Ambient air was allowed freely into the room.
|
Medium Exposure
n=77 Participants
Limited air filtration was used to partially reduce levels of pollution in the room relative to outside.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
Low Exposure
n=77 Participants
Doors and windows were closed and sealed and full filtration was used to maximally reduce pollution in the room.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
|---|---|---|---|
|
Systolic Blood Pressure (SBP)
|
122.3 mmHg
Standard Error 0.8
|
120.83 mmHg
Standard Error 0.7
|
119.9 mmHg
Standard Error 0.8
|
SECONDARY outcome
Timeframe: Over a 2 hour exposure period with the objective to assess change in DBP measured after 10 minutes in a time series of measurements over that time period.The unit of measurement, mmHg for the diastolic blood pressure.
Outcome measures
| Measure |
High Exposure
n=77 Participants
Ambient air was allowed freely into the room.
|
Medium Exposure
n=77 Participants
Limited air filtration was used to partially reduce levels of pollution in the room relative to outside.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
Low Exposure
n=77 Participants
Doors and windows were closed and sealed and full filtration was used to maximally reduce pollution in the room.
Air filtration and building envelop modifications: Air filters and closing and sealing of windows and doors was used to reduce infiltration of air pollution from outdoors in rooms next to major highways at rush hour.
|
|---|---|---|---|
|
Diastolic Blood Pressure (DBP)
|
69.9 mmHg
Standard Error 0.5
|
70.4 mmHg
Standard Error 0.5
|
71.0 mmHg
Standard Error 0.5
|
Adverse Events
High Exposure
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Medium Exposure
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Low Exposure
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place