Hypertension, Cardiovascular Diseases, Arterial Hypertension
Conditions
Keywords
Stage 1 hypertension, Arterial Stiffness
Brief summary
This is a clinical trial to determine whether 30 sessions of heat therapy in the form of hot water immersion is better than 30 sessions of traditional aerobic exercise training on blood pressure reduction in people with elevated or Stage 1 hypertension.
Detailed description
Hypertension accounts for more cardiovascular disease related deaths than any other modifiable risk factor. While exercise training can be effective at reducing blood pressure in some individuals, many people do not respond to exercise training, and many more are unwilling to undergo regular exercise training. Alternative options need to be explored. This is a clinical trial to determine whether 30 sessions of heat therapy in the form of hot water immersion is better than 30 sessions of traditional aerobic exercise training on blood pressure reduction in people with elevated blood pressure (hypertension). The investigators will evaluate known biomarkers of cardiovascular health. It is hypothesized that heat therapy will be superior to exercise training on blood pressure reduction.
Interventions
OTHERHeat Therapy Group
30 sessions of immersion in 40.5 degree celsius water for 45 minutes per session
30 sessions of aerobic exercise training for 45 minutes at 60% of VO2peak
Sponsors
Oregon Health and Science University
University of Oregon
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Intervention model description
Randomized parallel study design
Eligibility
Sex/Gender
ALL
Age
35 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Systolic Blood Pressure 120 mmHg or greater and less than 180 mmHg or Diastolic Blood Pressure of 80mmHg or greater and less than 120mmHg
Exclusion criteria
* Secondary hypertension; diagnosed cardiovascular disease other than hypertension; taking anti-hypertensive drugs; BMI of 35 or greater; fasting glucose greater than 125 mg/dl; women who are pregnant, nursing, or desiring to become pregnant.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention | 10 weeks | Ambulatory blood pressure (ABP) was measured at baseline (PRE) and after 30 heat therapy or exercise training sessions (POST) over the course of 8-10 weeks. Two individuals performed post-intervention testing after completing only 27 sessions (1 in each group). Participants arrived at the lab and were fitted with an oscillometric blood pressure cuff attached to an ambulatory blood pressure monitor. The monitor was programmed to inflate and assess blood pressure every 20 min during self-reported waking hours and every 60 min during self-reported sleeping hours. Waking and sleeping times and measurement frequency were replicated at POST within each participant. Ambulatory blood pressure data were analyzed as 24-h total for both systolic and diastolic blood pressure. Change was calculated as the value at the POST timepoint minus the value at the PRE timepoint. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Arterial Stiffness: Change in Carotid-femoral Pulse Wave Velocity (m/s) From Pre (Baseline) to Post (After 30 Sessions of Intervention) | 10 weeks | Carotid-femoral pulse wave velocity (m/s) was measured as a marker of arterial stiffness using a pressure transducing tonometer over the carotid artery and an inflated leg cuff to detect the femoral artery pulse waveform using air displacement at baseline (PRE) and after 30 heat therapy or exercise training sessions (POST) over the course of 8-10 weeks. Two individuals performed post-intervention testing after completing only 27 sessions (1 in each group). Change was calculated as the value at the POST timepoint minus the value at the PRE timepoint. |
Countries
United States
Participant flow
Recruitment details
Three enrollees declined to participate after being registered for the clinical trial (assigned a participant number) but before initiating the intervention.
Pre-assignment details
Protocol 2 participants consisted of a subset of participants from Protocol 1 (i.e. Participants were only eligible for Protocol 2 if they participated in Protocol 1). Not all participants who participated in Protocol 1 were qualified or interested to participate in Protocol 2.
Participants by arm
| Arm | Count |
|---|---|
| Heat Therapy Group Group will undergo 30 sessions of heat therapy over approximately 10 weeks. Sessions will require subjects to be immersed in hot water for up to 45 minutes per session.
Heat Therapy Group: 30 sessions of immersion in 40.5 degree celsius water for 45 minutes per session. | 21 |
| Aerobic Exercise Group Group will undergo 30 sessions of aerobic exercise training over approximately 10 weeks. Sessions will require subjects to exercise on a cycle ergometer for up to 45 minutes per session.
Aerobic Exercise Group: 30 sessions of aerobic exercise training consisting of a 5-minute warm-up of seated upright cycling at 30% VO2 peak, followed by 40 minutes of cycling at 60% VO2 peak, then a 5-minute cool down at 30% VO2 peak. | 20 |
| Total | 41 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Protocol 2 | Met exclusion criteria at Post timepoint | 1 | 1 |
| Protocol 2 | Withdrawal by Subject | 1 | 1 |
Baseline characteristics
| Characteristic | Heat Therapy Group | Aerobic Exercise Group | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 21 Participants | 20 Participants | 41 Participants |
| Age, Continuous | 47.57 years | 47.95 years | 47.76 years |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants | 0 Participants | 1 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 19 Participants | 20 Participants | 39 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 1 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) White | 19 Participants | 17 Participants | 36 Participants |
| Region of Enrollment United States | 21 participants | 20 participants | 41 participants |
| Sex: Female, Male Female | 8 Participants | 8 Participants | 16 Participants |
| Sex: Female, Male Male | 13 Participants | 12 Participants | 25 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 21 | 0 / 20 |
| other Total, other adverse events | 0 / 21 | 0 / 20 |
| serious Total, serious adverse events | 0 / 21 | 0 / 20 |
Outcome results
Primary
Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention
Ambulatory blood pressure (ABP) was measured at baseline (PRE) and after 30 heat therapy or exercise training sessions (POST) over the course of 8-10 weeks. Two individuals performed post-intervention testing after completing only 27 sessions (1 in each group). Participants arrived at the lab and were fitted with an oscillometric blood pressure cuff attached to an ambulatory blood pressure monitor. The monitor was programmed to inflate and assess blood pressure every 20 min during self-reported waking hours and every 60 min during self-reported sleeping hours. Waking and sleeping times and measurement frequency were replicated at POST within each participant. Ambulatory blood pressure data were analyzed as 24-h total for both systolic and diastolic blood pressure. Change was calculated as the value at the POST timepoint minus the value at the PRE timepoint.
Time frame: 10 weeks
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Heat Therapy Group | Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention | Change in systolic Ambulatory Blood Pressure | -1 mmHg |
| Heat Therapy Group | Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention | Change in diastolic Ambulatory Blood Pressure | 0 mmHg |
| Aerobic Exercise Group | Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention | Change in systolic Ambulatory Blood Pressure | 0 mmHg |
| Aerobic Exercise Group | Blood Pressure Reduction: Change in Systolic and Diastolic Ambulatory Blood Pressure (mmHg) After 30 Sessions of Intervention | Change in diastolic Ambulatory Blood Pressure | 1 mmHg |
Secondary
Arterial Stiffness: Change in Carotid-femoral Pulse Wave Velocity (m/s) From Pre (Baseline) to Post (After 30 Sessions of Intervention)
Carotid-femoral pulse wave velocity (m/s) was measured as a marker of arterial stiffness using a pressure transducing tonometer over the carotid artery and an inflated leg cuff to detect the femoral artery pulse waveform using air displacement at baseline (PRE) and after 30 heat therapy or exercise training sessions (POST) over the course of 8-10 weeks. Two individuals performed post-intervention testing after completing only 27 sessions (1 in each group). Change was calculated as the value at the POST timepoint minus the value at the PRE timepoint.
Time frame: 10 weeks
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Heat Therapy Group | Arterial Stiffness: Change in Carotid-femoral Pulse Wave Velocity (m/s) From Pre (Baseline) to Post (After 30 Sessions of Intervention) | -0.0 meters/second |
| Aerobic Exercise Group | Arterial Stiffness: Change in Carotid-femoral Pulse Wave Velocity (m/s) From Pre (Baseline) to Post (After 30 Sessions of Intervention) | -0.1 meters/second |