Trial Outcomes & Findings for Wood Smoke Interventions in Native American Populations (NCT NCT02240069)
NCT ID: NCT02240069
Last Updated: 2022-12-01
Results Overview
Mean of up to two post-intervention measures of forced expiratory volume at one second (FEV1), liters
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
149 participants
Primary outcome timeframe
Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.
Results posted on
2022-12-01
Participant Flow
For this pre/post study recruited and consented participants completed baseline measures during a pre-intervention period (n=149). Randomization to arms occurred after the first (baseline) period and before the second (post-intervention) period. Six participants dropped out of the study before the randomization process. Thus, only 143 participants were randomized to a treatment arm.
Unit of analysis: Household
Participant milestones
| Measure |
Education (Tx1)
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Overall Study
STARTED
|
49 47
|
47 46
|
47 45
|
|
Overall Study
COMPLETED
|
44 43
|
42 41
|
45 43
|
|
Overall Study
NOT COMPLETED
|
5 4
|
5 5
|
2 2
|
Reasons for withdrawal
| Measure |
Education (Tx1)
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Overall Study
Withdrawal by Subject
|
5
|
5
|
2
|
Baseline Characteristics
Specific age for one participant not disclosed; all participants 55 years or older
Baseline characteristics by cohort
| Measure |
Education (Tx1)
n=49 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=47 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=47 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
Total
n=143 Participants
Total of all reporting groups
|
|---|---|---|---|---|
|
Age, Continuous
|
69.8 years
STANDARD_DEVIATION 9.3 • n=49 Participants • Specific age for one participant not disclosed; all participants 55 years or older
|
69.8 years
STANDARD_DEVIATION 9.5 • n=47 Participants • Specific age for one participant not disclosed; all participants 55 years or older
|
68.9 years
STANDARD_DEVIATION 8.7 • n=46 Participants • Specific age for one participant not disclosed; all participants 55 years or older
|
69.6 years
STANDARD_DEVIATION 9.2 • n=142 Participants • Specific age for one participant not disclosed; all participants 55 years or older
|
|
Sex: Female, Male
Female
|
36 Participants
n=49 Participants
|
33 Participants
n=47 Participants
|
31 Participants
n=47 Participants
|
100 Participants
n=143 Participants
|
|
Sex: Female, Male
Male
|
13 Participants
n=49 Participants
|
14 Participants
n=47 Participants
|
16 Participants
n=47 Participants
|
43 Participants
n=143 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
3 Participants
n=49 Participants
|
1 Participants
n=47 Participants
|
1 Participants
n=47 Participants
|
5 Participants
n=143 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
46 Participants
n=49 Participants
|
46 Participants
n=47 Participants
|
46 Participants
n=47 Participants
|
138 Participants
n=143 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=49 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=143 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
48 Participants
n=49 Participants
|
43 Participants
n=47 Participants
|
47 Participants
n=47 Participants
|
138 Participants
n=143 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=49 Participants
|
1 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
1 Participants
n=143 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=49 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=143 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=49 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=143 Participants
|
|
Race (NIH/OMB)
White
|
0 Participants
n=49 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=143 Participants
|
|
Race (NIH/OMB)
More than one race
|
1 Participants
n=49 Participants
|
3 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
4 Participants
n=143 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=49 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=47 Participants
|
0 Participants
n=143 Participants
|
|
Forced expiratory volume in 1 second (FEV1)
|
2.1 liters
STANDARD_DEVIATION 0.7 • n=45 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.1 liters
STANDARD_DEVIATION 0.6 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.0 liters
STANDARD_DEVIATION 0.8 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.0 liters
STANDARD_DEVIATION 0.7 • n=133 Participants • Valid spirometry measures captured for 133 of 143 participants
|
|
Forced vital capacity (FVC)
|
2.6 liters
STANDARD_DEVIATION 0.8 • n=45 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.6 liters
STANDARD_DEVIATION 0.7 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.5 liters
STANDARD_DEVIATION 0.9 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
2.6 liters
STANDARD_DEVIATION 0.8 • n=133 Participants • Valid spirometry measures captured for 133 of 143 participants
|
|
FEV1/FVC
|
0.79 ratio
STANDARD_DEVIATION 0.08 • n=45 Participants • Valid spirometry measures captured for 133 of 143 participants
|
0.80 ratio
STANDARD_DEVIATION 0.07 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
0.79 ratio
STANDARD_DEVIATION 0.08 • n=44 Participants • Valid spirometry measures captured for 133 of 143 participants
|
0.79 ratio
STANDARD_DEVIATION 0.08 • n=133 Participants • Valid spirometry measures captured for 133 of 143 participants
|
|
Systolic blood pressure
|
132 mmHg
STANDARD_DEVIATION 18 • n=42 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
143 mmHg
STANDARD_DEVIATION 19 • n=45 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
137 mmHg
STANDARD_DEVIATION 20 • n=43 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
137 mmHg
STANDARD_DEVIATION 19 • n=130 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
|
Diastolic blood pressure
|
74 mmHg
STANDARD_DEVIATION 11 • n=42 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
79 mmHg
STANDARD_DEVIATION 10 • n=45 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
77 mmHg
STANDARD_DEVIATION 14 • n=43 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
77 mmHg
STANDARD_DEVIATION 12 • n=130 Participants • Valid blood pressure measures captured for 130 of 143 participants
|
PRIMARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.Population: Valid post-intervention spirometry measures captured for 127 of 143 participants
Mean of up to two post-intervention measures of forced expiratory volume at one second (FEV1), liters
Outcome measures
| Measure |
Education (Tx1)
n=43 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=40 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=44 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention FEV1
|
1.9 liters
Standard Deviation 0.7
|
2.1 liters
Standard Deviation 0.6
|
2.0 liters
Standard Deviation 0.6
|
PRIMARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.Population: Valid post-intervention spirometry measures captured for 127 of 143 participants
Mean of up to two post-intervention measures of forced vital capacity (FVC), liters
Outcome measures
| Measure |
Education (Tx1)
n=43 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=40 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=44 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention FVC
|
2.4 liters
Standard Deviation 0.7
|
2.7 liters
Standard Deviation 0.7
|
2.5 liters
Standard Deviation 0.7
|
PRIMARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.Population: Valid post-intervention spirometry measures captured for 127 of 143 participants
Mean of up to two post-intervention measures of forced expiratory volume at one second (FEV1) / forced vital capacity (FVC)
Outcome measures
| Measure |
Education (Tx1)
n=43 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=40 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=44 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention FEV1/FVC Ratio
|
0.78 ratio
Standard Deviation 0.08
|
0.79 ratio
Standard Deviation 0.08
|
0.80 ratio
Standard Deviation 0.08
|
PRIMARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.Population: Valid post-intervention blood pressure measures captured for 128 of 143 participants
Mean of up to two post-intervention measures of systolic blood pressure, millimeters of mercury (mmHg)
Outcome measures
| Measure |
Education (Tx1)
n=42 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=41 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=45 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention Systolic Blood Pressure
|
132 millimeters of mercury (mmHg)
Standard Deviation 16
|
139 millimeters of mercury (mmHg)
Standard Deviation 17
|
136 millimeters of mercury (mmHg)
Standard Deviation 22
|
PRIMARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Health measures were collected at two visits during both winter periods with each visit separated by at least three weeks.Population: Valid post-intervention blood pressure measures captured for 128 of 143 participants
Mean of up to two post-intervention measures of diastolic blood pressure, millimeters of mercury (mmHg)
Outcome measures
| Measure |
Education (Tx1)
n=42 Participants
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=41 Participants
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=45 Participants
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention Diastolic Blood Pressure
|
75 millimeters of mercury (mmHg)
Standard Deviation 11
|
78 millimeters of mercury (mmHg)
Standard Deviation 11
|
76 millimeters of mercury (mmHg)
Standard Deviation 13
|
SECONDARY outcome
Timeframe: Each participant was followed during a pre-intervention baseline (Winter 1) and a post-intervention follow-up period (Winter 2). Indoor 48-hour PM2.5 average concentration was measured at two post-intervention visits separated by at least three weeks.Population: Valid post-intervention PM2.5 measures captured for 123 of 143 households
Post-intervention average Indoor fine particulate matter (PM2.5) concentration
Outcome measures
| Measure |
Education (Tx1)
n=43 Household
Education on best burn practices
Education (Tx1): Education on best burn practices
|
Air Filtration Unit Treatment (Tx2)
n=39 Household
A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove.
Air Filtration Unit Treatment (Tx2): A 20" x 18" Filtrete air filtration unit (3M, St. Paul, MN) will be placed in the same room as the wood stove
|
Placebo Intervention (Tx3)
n=41 Household
A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
Placebo Intervention (Tx3): A 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.
|
|---|---|---|---|
|
Post-intervention Indoor Fine Particulate Matter (PM2.5)
|
38.8 microgram/cubic meter
Standard Deviation 33.9
|
30.5 microgram/cubic meter
Standard Deviation 51.5
|
41.6 microgram/cubic meter
Standard Deviation 39.2
|
Adverse Events
Education (Tx1)
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Air Filtration Unit Treatment (Tx2)
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Placebo Intervention (Tx3)
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