Sex Disparities in Hypoxic Sympatholysis and Impact of Obesity

Early Phase 1

Recruiting

• Conditions: Healthy; Vasoconstriction; Vasodilation; Obesity
• Interventions: Other: Hypoxia Exposure; Drug: Phenylephrine; Drug: Dexmedetomidine; Drug: Phentolamine; Drug: Norepinephrine

• Registration Number: NCT04436731
• Lead Sponsor: University of Missouri-Columbia

Brief Summary

Patients with sleep apnea are at increased risk of developing cardiovascular disease - with women at potentially greater risk than men. Contributing mechanisms are not well understood, but may be related to how women respond to low oxygen and, given over 70% of patients with sleep apnea are obese, the impact of obesity. This project seeks to increase our understanding of mechanisms that may contribute to sex differences in the cardiovascular response to low oxygen with the hope that this knowledge will improve the efficacy of current therapies and support the discovery of novel therapeutics.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-06-08
• Study First Submitted QC: 2020-06-15
• Study First Posted: 2020-06-18
• Study Start: 2020-12-09
• Status Verified: 2024-05
• Last Update Submitted: 2024-05-02
• Last Update Posted: 2024-05-03
• Primary Completion: 2025-06-30
• Study Completion: 2025-06-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 104

Inclusion Criteria

• 18-45 years of age (premenopausal)
• Healthy weight (BMI ≥18 and ≤25 kg/m2)
• Obese (BMI ≥30 kg/m2)

Exclusion Criteria

• Pregnancy, breastfeeding, oral hormonal contraceptive use
• Diagnosed sleep apnea or Oxygen desaturation index >10 events/hr
• Current smoking/Nicotine use
• Increased risk of bleeding, pro-coagulant disorders, clotting disorders, anticoagulation therapy
• Nerve/neurologic disease
• Cardiovascular, hepatic, renal, respiratory disease
• Blood pressure ≥140/90 mmHg
• Diabetes, Polycystic ovarian syndrome
• Communication barriers
• Prescription medications, Sensitivity to lidocaine

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Hypoxia Exposure	Dexmedetomidine	A physician will place a catheter in the brachial artery for intra-arterial pharmacological infusions. The following drugs will be administered to each participant under room air (normoxic) and low oxygen (hypoxic) conditions: phenylephrine, dexmedetomidine, norepinephrine, phentolamine (see Interventions for details).
Hypoxia Exposure	Hypoxia Exposure	A physician will place a catheter in the brachial artery for intra-arterial pharmacological infusions. The following drugs will be administered to each participant under room air (normoxic) and low oxygen (hypoxic) conditions: phenylephrine, dexmedetomidine, norepinephrine, phentolamine (see Interventions for details).
Hypoxia Exposure	Phenylephrine	A physician will place a catheter in the brachial artery for intra-arterial pharmacological infusions. The following drugs will be administered to each participant under room air (normoxic) and low oxygen (hypoxic) conditions: phenylephrine, dexmedetomidine, norepinephrine, phentolamine (see Interventions for details).
Hypoxia Exposure	Phentolamine	A physician will place a catheter in the brachial artery for intra-arterial pharmacological infusions. The following drugs will be administered to each participant under room air (normoxic) and low oxygen (hypoxic) conditions: phenylephrine, dexmedetomidine, norepinephrine, phentolamine (see Interventions for details).
Hypoxia Exposure	Norepinephrine	A physician will place a catheter in the brachial artery for intra-arterial pharmacological infusions. The following drugs will be administered to each participant under room air (normoxic) and low oxygen (hypoxic) conditions: phenylephrine, dexmedetomidine, norepinephrine, phentolamine (see Interventions for details).

Primary Outcome Measures

Name	Time	Method
Change in forearm vascular conductance with intra-arterial drug infusion	Continuous measurement of vascular conductance during infusion of each drug (final 3 min of normoxia and hypoxia).	Vascular conductance is an index of vascular tone and is measured using a technique called venous occlusion plethysmography.

Trial Locations

Locations (1)

University of Missouri-Columbia; 🇺🇸 Columbia, Missouri, United States