Menopause, Aging
Conditions
Keywords
Thermoregulation, Heat Stress
Brief summary
The frequency and severity of heat waves has increased in the last decades. Older adults (over 65 years) have impaired responses to heat stress making them at increased risk for adverse events. Previous heat waves report that women over 65 experience worse health outcomes than any other age group and age matched men. Aging and reproductive hormones, specifically estrogen, independently alter responses to heat stress. However, the combined effects of low estrogen following menopause and aging on the response to heat stress are unknown. In this study, the investigators will identify the role of estrogen in pre and post menopausal women on thermoregulatory responses to heat stress.
Detailed description
Premenopausal and postmenopausal women will be recruited and different interventions will be given to each group. To mimic a postmenopausal hormone profile, premenopausal women will be given a GnRH antagonist, which acutely reduces estrogen concentrations. This induces a temporary post-menopausal state without compounding aging effects. Postmenopausal women will be given a transdermal estradiol patch to acutely raise estrogen concentrations. Supplementing estrogen in postmenopausal women allows for the effect of menopausal low estrogen concentration to be removed from the physiological effects of aging. Subjects sign an informed consent form and undergo a medical screening prior to participation. The screening includes a physical exam, anthropometry, chemical and lipid profiles. Each subject will complete 6 (3 for each treatment) experimental trials. For each intervention, participants will complete one passive heating experiment first, followed by two active heating experiments.
Interventions
DRUGElagolix Oral Tablet
2 x 200 mg tablet
DRUGEstradiol patch
0.05 mg/day patch
OTHERcellulose placebo
placebo tablet
OTHERplacebo patch
placebo patch
Sponsors
Penn State University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Masking description
Double (participant, investigator)
Intervention model description
Subjects participate in 6 experiments, 3 for each treatment (Elagolix OR Estradiol and placebo). The order of treatment is random.
Eligibility
Sex/Gender
FEMALE
Age
42 Years to 64 Years
Healthy volunteers
Yes
Inclusion criteria
* Women ages 42-64
Exclusion criteria
* Chron's disease, diverticulitis, or similar gastrointestinal disease * Abnormal resting exercise electrocardiogram (ECG) * Tobacco use * High-risk determined by the Atherosclerotic Cardiovascular Disease (CVD) Risk Factor * Assessment * Using hormone therapy * Using hormonal contraceptives
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Local Sweat Rate | Monitored continuously during both 3 hour passive heating experiments (Visit 1 and Visit 3 approx 3 weeks) | A small sweat capsule is placed on the forearm for the duration of whole body heating. |
| Core Temperature | Monitored continuously during all 3 hour experimental visits (6 total average of 3 weeks) | Changes in body temperature are measured through a telemetry pill swallowed before each experiment. |
| Skin Blood Flow | Monitored continuously during both 3 hour passive heating experiments (Visit 1 and Visit 3 approx 3 weeks) | Skin blood flow response to whole body heating is continuously monitored |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Body Mass | Baseline and following 3 hr experimental visit (6 total visits for study completion, an average of 3 weeks) | Body mass is measured on a scale. |
| Skin Temperature | Calculated continuously for the duration of each 3 hr experimental visit (6 total visits for study completion, an average of 3 weeks) | Mean skin temperature is calculated from a weighted average of skin temperature from 4 different sites. |
Countries
United States
Contacts
Primary ContactW. Larry Kenney, Ph.D.
Backup ContactOlivia K. Leach, MS
Outcome results
None listed