Autonomic Regulation of Blood Pressure in Premature and Early Menopausal Women

What this trial studies

This is a cross-sectional study in which the investigators will determine the impact of premature/early menopause on MSNA, BP and baroreflex sensitivity in younger (≤49 yr old) and older (≥50 yr old) women. Specifically, aim one will determine mechanisms driving autonomic dysregulation of BP in premature and early menopausal women and aim two will determine mechanisms driving autonomic dysregulation of BP in older menopausal women. The study design outlined below will permit testing of aim one and aim two.

Conditions in scope

• Hypertension
• Menopause, Premature
• Menopause
• Blood Pressure

Interventions

• Microneurography to measure muscle sympathetic nerve activity (MSNA) (Diagnostic Test) — Microneurography is a direct measurement of electrical activity of peripheral sympathetic nerves
• Baroreflex sensitivity testing (Diagnostic Test) — Two arms of the baroreflex that will be tested in this study are sympathetic and cardiovagal. Static baroreflex is tested during baseline resting conditions and dynamic baroreflex is tested during Valsalva maneuvers.
• Sympathoexcitatory Maneuvers (Diagnostic Test) — Cold Pressor Test (CPT) and Upper extremity fatiguing contraction with post exercise circulatory occlusion (PECO) will be performed
• Blood tests (Diagnostic Test) — Serum FSH, estrogen, progesterone, and testosterone will be measured

Who can join

Women only · Ages 35 Years to 70 Years · Accepts healthy volunteers.

Inclusion criteria

• Aged 35-49 or 50-70 years of age who experienced premature (\<40) or early (≤45) menopause
• Premenopausal 35-49 years of age
• Typical-age menopause (i.e., after 45 years of age), who are between 50-70 years old
• Menopause will be confirmed by subject report of amenorrhea for 12 months and serum FSH of \>30 mIU/mL

Exclusion criteria

• Current nicotine/tobacco use within the past six months
• Are diabetic or asthmatic
• Have diagnosed significant carotid stenosis
• Have a history of significant autonomic dysfunction, heart disease, respiratory disease or a severe neurologic condition such as stroke or traumatic brain injury.
• Have existing metabolic or endocrine abnormities
• Take any heart/blood pressure medications that are determined to interfere with study outcomes
• IF the participant is premenopausal AND currently taking OC or other exogenous steroids that are determined to interfere with study outcomes
• Females who classify as having early or premature menopause AND are not willing to discontinue OC or MHT in order to complete the study

Eligibility wording paraphrased from the public record. View the full criteria on ClinicalTrials.gov before contacting a site.

Where it’s happening

Status & timeline

• Overall status: Recruiting
• Study type: Observational
• Phase: N/A
• Start date: 2019-10-01
• Primary completion: 2026-12-30
• Last update posted: 2026-01-08
• First posted: 2020-06-19

Sponsor & contact

Lead sponsor: University of Minnesota (Other)

For trial site contact information, use the official record at ClinicalTrials.gov. Contact details change frequently and the public record is the source of truth.

Outcome measures

Primary outcomes

• Muscle Sympathetic Nerve Activity (MSNA) (bursts per minute) (3 hours)
  Muscle sympathetic nerve activity (MSNA) is a measurement of sympathetic activity. This is measured by two small needles are inserted behind or on the side of the knee, one needle is an acupuncture needle and one needle is a small recording microelectrode (same size as the acupuncture needle). Outcome will be reported in units of bursts per minute.
• Muscle Sympathetic Nerve Activity (MSNA) (bursts/100 heart beats) (3 hours)
  Muscle sympathetic nerve activity (MSNA) is a measurement of sympathetic activity. This is measured by two small needles are inserted behind or on the side of the knee, one needle is an acupuncture needle and one needle is a small recording microelectrode (same size as the acupuncture needle). Outcome will be reported in units of bursts per 100 heart beats.
• Cardiac baroreflex sensitivity (3 hours)
  Baroreflex sensitivity will be derived from electrocardiogram measurements and blood pressure measurements during the baseline rest period and by performing a modified valsalva maneuver which involves exhaling against 30-40 mmHg of pressure over 15 seconds after a normal inhalation. Outcome will be reported in units as ms/mmHg.
• Sympathetic baroreflex sensitivity (3 hours)
  Baroreflex sensitivity will be derived from electrocardiogram measurements and blood pressure measurements during the baseline rest period and by performing a modified valsalva maneuver which involves exhaling against 30-40 mmHg of pressure over 15 seconds after a normal inhalation. Outcome will be reported in units of MSNA bursts/mmHg.
• Systolic Blood Pressure (mmHg) (3 hours)
  Blood pressure is measured using a non-invasive blood pressure cuff secured to the middle or ring finger and reported in units of mmHg.

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