Mild Dehydration
Conditions
Keywords
Dehydration
Brief summary
The goal of this project is determine how acute mild dehydration impacts blood pressure control at rest and during static exercise. This protocol will test healthy young and older adults in a normally hydrated and dehydrated condition.
Detailed description
The purpose of this project is determine how acute mild dehydration impacts blood pressure control at rest and during static exercise. Additionally, we will determine whether or not the sympathetic nervous system has a role in mediating blood pressure control at rest and during static exercise. This protocol will test healthy young and older adults in a normally hydrated and dehydrated condition. This will allow for a within participant comparison. Additionally, we will later determine if age alters blood pressure control at rest or during static exercise.
Interventions
OTHERNormal hydration
see description in 'arms'
OTHERDehydration
see description in 'arms'
Sponsors
National Heart, Lung, and Blood Institute (NHLBI)
National Institute of General Medical Sciences (NIGMS)
University of Delaware
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Investigator)
Intervention model description
Normal Hydration and Dehydration
Eligibility
Sex/Gender
ALL
Age
20 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
(Young): • age: 20-35 years old
Exclusion criteria
(Young): * high blood pressure (\>140/90 mmHg) * history of cardiovascular disease * history of cancer * history of diabetes * history of kidney disease * obesity (BMI \> 30 kg/m2) * smoking or tobacco use * current pregnancy * nursing mothers * communication barriers Inclusion Criteria (Older): * age: 60-75 years old * ECG within normal limits * screening blood panel within normal limits
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Blood Pressure Variability | During experimental visits 1 and 2 | Blood pressure variability (BPV) was calculated using standard deviation and using the average real variability index of blood pressure values. The average real variability index calculates the average of absolute differences between consecutive BP measurements and is thought to provide further prognostic value compared with traditional measures of BPV. |
| Blood Pressure Reactivity - Handgrip Exercise | During experimental visits 1 and 2 | Change in systolic blood pressure during the second-minute handgrip exercise minus compared to pre-exercise baseline (i.e., at rest). |
Countries
United States
Participant flow
Pre-assignment details
All participants completed both conditions.
Participants by arm
| Arm | Count |
|---|---|
| All Study Participants All Study Participants | 35 |
| Total | 35 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Screening failure | 4 | 4 |
| Overall Study | Withdrawal by PI | 0 | 1 |
| Overall Study | Withdrawal by Subject | 3 | 4 |
Baseline characteristics
| Characteristic | All Study Participants |
|---|---|
| Age, Continuous | 47 years STANDARD_DEVIATION 22 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 0 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 35 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants |
| Race (NIH/OMB) Asian | 3 Participants |
| Race (NIH/OMB) Black or African American | 4 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 28 Participants |
| Region of Enrollment United States | 35 Participants |
| Sex: Female, Male Female | 27 Participants |
| Sex: Female, Male Male | 8 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 35 | 0 / 35 |
| other Total, other adverse events | 0 / 35 | 0 / 35 |
| serious Total, serious adverse events | 0 / 35 | 0 / 35 |
Outcome results
Primary
Blood Pressure Reactivity - Handgrip Exercise
Change in systolic blood pressure during the second-minute handgrip exercise minus compared to pre-exercise baseline (i.e., at rest).
Time frame: During experimental visits 1 and 2
Population: 4 adults were excluded from this analysis due to technical difficulties
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Normal Hydration | Blood Pressure Reactivity - Handgrip Exercise | 20 mmHg | Standard Deviation 11 |
| Dehydration | Blood Pressure Reactivity - Handgrip Exercise | 18 mmHg | Standard Deviation 8 |
Primary
Blood Pressure Variability
Blood pressure variability (BPV) was calculated using standard deviation and using the average real variability index of blood pressure values. The average real variability index calculates the average of absolute differences between consecutive BP measurements and is thought to provide further prognostic value compared with traditional measures of BPV.
Time frame: During experimental visits 1 and 2
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Normal Hydration | Blood Pressure Variability | 2.6 mmHg | Standard Deviation 1.1 |
| Dehydration | Blood Pressure Variability | 2.5 mmHg | Standard Deviation 0.9 |