Trial Outcomes & Findings for Cardiovascular Responses to Heat Waves in the Elderly (NCT NCT04538144)
NCT ID: NCT04538144
Last Updated: 2025-10-23
Results Overview
Core body temperature will be measured via a telemetric pill or rectal temperature probe.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
59 participants
Primary outcome timeframe
Prior to and after the 3-hour simulated heat wave exposure.
Results posted on
2025-10-23
Participant Flow
18 participants were either screened out or withdrew before randomization.
Participant milestones
| Measure |
Younger Participants: Hot and Humid First, Then Hot and Dry
Individuals aged 18-39 years that had the hot/humid trial first and the hot/dry trial second.
|
Younger Participants: Hot and Dry First, Then Hot and Humid
Individuals aged 18-39 years that had the hot/dry trial first and the hot/humid trial second.
|
Older Participants: Hot and Humid First, Then Hot and Dry
Individuals aged 65 years or older that had the hot/humid trial first and the hot/dry trial second.
|
Older Participants: Hot and Dry First, Then Hot and Humid
Individuals aged 65 years or older that had the hot/dry trial first and the hot/humid trial second.
|
|---|---|---|---|---|
|
First Intervention (3 Hours)
STARTED
|
9
|
11
|
8
|
13
|
|
First Intervention (3 Hours)
COMPLETED
|
9
|
11
|
8
|
13
|
|
First Intervention (3 Hours)
NOT COMPLETED
|
0
|
0
|
0
|
0
|
|
Washout (1 Week)
STARTED
|
9
|
11
|
8
|
13
|
|
Washout (1 Week)
COMPLETED
|
9
|
11
|
8
|
12
|
|
Washout (1 Week)
NOT COMPLETED
|
0
|
0
|
0
|
1
|
|
Second Intervention (3 Hours)
STARTED
|
9
|
11
|
8
|
12
|
|
Second Intervention (3 Hours)
COMPLETED
|
9
|
11
|
8
|
12
|
|
Second Intervention (3 Hours)
NOT COMPLETED
|
0
|
0
|
0
|
0
|
Reasons for withdrawal
| Measure |
Younger Participants: Hot and Humid First, Then Hot and Dry
Individuals aged 18-39 years that had the hot/humid trial first and the hot/dry trial second.
|
Younger Participants: Hot and Dry First, Then Hot and Humid
Individuals aged 18-39 years that had the hot/dry trial first and the hot/humid trial second.
|
Older Participants: Hot and Humid First, Then Hot and Dry
Individuals aged 65 years or older that had the hot/humid trial first and the hot/dry trial second.
|
Older Participants: Hot and Dry First, Then Hot and Humid
Individuals aged 65 years or older that had the hot/dry trial first and the hot/humid trial second.
|
|---|---|---|---|---|
|
Washout (1 Week)
Withdrawal by Subject
|
0
|
0
|
0
|
1
|
Baseline Characteristics
Cardiovascular Responses to Heat Waves in the Elderly
Baseline characteristics by cohort
| Measure |
Younger Participants: Hot and Humid First, Then Hot and Dry
n=9 Participants
Individuals aged 18-39 years that had the hot/humid trial first and the hot/dry trial second.
|
Younger Participants: Hot and Dry First, Then Hot and Humid
n=11 Participants
Individuals aged 18-39 years that had the hot/dry trial first and the hot/humid trial second.
|
Older Participants: Hot and Humid First, Then Hot and Dry
n=8 Participants
Individuals aged 65 years or older that had the hot/humid trial first and the hot/dry trial second.
|
Older Participants: Hot and Dry First, Then Hot and Humid
n=12 Participants
Individuals aged 65 years or older that had the hot/dry trial first and the hot/humid trial second.
|
Total
n=40 Participants
Total of all reporting groups
|
|---|---|---|---|---|---|
|
Age, Continuous
|
30 years
STANDARD_DEVIATION 6 • n=5 Participants
|
29 years
STANDARD_DEVIATION 4 • n=7 Participants
|
70 years
STANDARD_DEVIATION 4 • n=5 Participants
|
71 years
STANDARD_DEVIATION 4 • n=4 Participants
|
50 years
STANDARD_DEVIATION 21 • n=21 Participants
|
|
Sex: Female, Male
Female
|
4 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
6 Participants
n=5 Participants
|
4 Participants
n=4 Participants
|
20 Participants
n=21 Participants
|
|
Sex: Female, Male
Male
|
5 Participants
n=5 Participants
|
5 Participants
n=7 Participants
|
2 Participants
n=5 Participants
|
8 Participants
n=4 Participants
|
20 Participants
n=21 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
1 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
3 Participants
n=21 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
8 Participants
n=5 Participants
|
10 Participants
n=7 Participants
|
7 Participants
n=5 Participants
|
12 Participants
n=4 Participants
|
37 Participants
n=21 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Asian
|
2 Participants
n=5 Participants
|
2 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
4 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Black or African American
|
1 Participants
n=5 Participants
|
3 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
1 Participants
n=4 Participants
|
6 Participants
n=21 Participants
|
|
Race (NIH/OMB)
White
|
6 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
7 Participants
n=5 Participants
|
11 Participants
n=4 Participants
|
30 Participants
n=21 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Region of Enrollment
United States
|
9 participants
n=5 Participants
|
11 participants
n=7 Participants
|
8 participants
n=5 Participants
|
12 participants
n=4 Participants
|
40 participants
n=21 Participants
|
PRIMARY outcome
Timeframe: Prior to and after the 3-hour simulated heat wave exposure.Core body temperature will be measured via a telemetric pill or rectal temperature probe.
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=20 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=20 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Change in Core Body Temperature
|
.68 degrees Celsius (°C)
Standard Deviation .27
|
1.37 degrees Celsius (°C)
Standard Deviation .42
|
.58 degrees Celsius (°C)
Standard Deviation .25
|
1.02 degrees Celsius (°C)
Standard Deviation .32
|
PRIMARY outcome
Timeframe: Prior to, during, and after each simulated heat wave exposure; approximately 20 min eachChange in peak mitral annular systolic velocity was measured by tissue doppler imaging.
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=20 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=20 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Change in Peak Mitral Annular Systolic Velocity (S')
|
1.46 cm/s
Standard Deviation 1.54
|
3.33 cm/s
Standard Deviation 2.05
|
1.39 cm/s
Standard Deviation 1.31
|
2.09 cm/s
Standard Deviation 1.29
|
SECONDARY outcome
Timeframe: At the end of the 3-hour simulated heat wave exposure.Population: It should be noted that only 17 older participants for the hot/dry trial and 19 participants for the hot/humid trial were analyzed due to missing data/equipment issues.
Skin temperature will be measured from small temperature sensitive electrodes attached to the participant's skin.
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=17 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=19 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Ending Skin Temperature
|
37.57 degrees Celsius (°C)
Standard Deviation .73
|
37.37 degrees Celsius (°C)
Standard Deviation .85
|
36.65 degrees Celsius (°C)
Standard Deviation .83
|
36.05 degrees Celsius (°C)
Standard Deviation .58
|
SECONDARY outcome
Timeframe: At the end of the 3-hour simulated heat wave exposure.Heart rate will be measured via ECG electrodes attached to the participant
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=20 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=20 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Ending Heart Rate
|
82 beats per minute (bpm)
Standard Deviation 9
|
87 beats per minute (bpm)
Standard Deviation 15
|
80 beats per minute (bpm)
Standard Deviation 10
|
81 beats per minute (bpm)
Standard Deviation 14
|
SECONDARY outcome
Timeframe: At the end of the 3-hour simulated heat wave exposure.Population: It should be noted that only 19 participants were analyzed in the Hot/Humid arm because of missing data/equipment issues.
Arterial blood pressure will be measured using a standard arm blood pressure cuff.
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=20 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=20 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=19 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Ending Mean Arterial Pressure
|
77 mmHg
Standard Deviation 7
|
76 mmHg
Standard Deviation 10
|
78 mmHg
Standard Deviation 5
|
76 mmHg
Standard Deviation 8
|
SECONDARY outcome
Timeframe: Prior to and after the 3-hour simulated heat wave exposure.Population: It should be known that only 16 participants in the hot/dry trials (younger and older) and the hot/humid trial (younger) and only 14 participants in the hot/humid trial (older) were analyzed due to missing data/equipment malfunction.
Cardiac output (how much blood is ejected from the heart per minute) was measured using echocardiography.
Outcome measures
| Measure |
Younger Participants- Hot and Dry
n=16 Participants
Individuals aged 18-39 years.
|
Older Participants- Hot and Dry
n=16 Participants
Individuals aged 65 years or older.
|
Younger Participants: Hot and Humid
n=16 Participants
Individuals aged 18-39 years.
|
Older Participants: Hot and Humid
n=14 Participants
Individuals aged 65 years or older.
|
|---|---|---|---|---|
|
Change in Cardiac Output
|
.88 L/min
Standard Deviation .77
|
.75 L/min
Standard Deviation .82
|
.38 L/min
Standard Deviation .52
|
.76 L/min
Standard Deviation .96
|
Adverse Events
Younger Participants: Hot and Dry
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Older Participants: Hot and Dry
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Younger Participants: Hot and Humid
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Older Participants: Hot and Humid
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
Dr. Craig Crandall
Institute for Exercise and Environmental Medicine
Phone: 214-345-4623
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place