Differing Levels of Hypoglycemia

November 5, 2025 updated by: Stephen N. Davis, MBBS, University of Maryland, Baltimore

Mechanisms of Hypoglycemia Associated Autonomic Dysfunction, Differing Levels of Hypoglycemia

Hypoglycemia can produce a spectrum of pro-inflammatory and pro-atherothrombotic changes. To date no studies appear to have investigated the effects of differing levels of hypoglycemia on the vasculature and pro-atherothrombotic balance during hypoglycemia in healthy man. The specific aim of our study will be to determine the effects of differing levels of hypoglycemia on in-vivo vascular biologic mechanisms in a healthy population.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Recent large randomized multicenter trials have investigated the effects of lowering blood glucose levels towards normal in both inpatient and ambulatory care/community settings. All studies have reported increasing prevalence and incidence of hypoglycemia as glucose levels approach normal. In fact, the occurrence of hypoglycemia was so problematic that some hospital based studies were halted and the target recommendations for glucose levels in critically unwell patients have been increased. Similarly three recent large glucose control and complications trials in type 2 diabetes mellitus (DM) have reported significantly high rates of hypoglycemia in intensively treated type 2 DM individuals. In two of these studies (VADT, ADVANCE) there was a highly significant association between severe hypoglycemia (glucose low enough to cause neurologic impairment) and serious cardiac events and increased death. Furthermore, in two studies performed in the USA (VADT, ACCORD), severe hypoglycemia occurring in the standard/conventionally treated group produced even more serious adverse cardiac effects as compared to the intensively treated group. The in-vivo mechanism(s) responsible for the above findings could not be identified from the above studies. Surprisingly there is very limited data available regarding the effects of hypoglycemia on in-vivo vascular biology. Previously, in vitro work has determined that epinephrine, norepinephrine, growth hormone, glucagon, and corticosteroids (all counterregulatory hormones) can have vascular biologic effects (platelet aggregation, fibrinolytic balance, increases in pro-inflammatory markers and changes in endothelial function). Three recent studies from my own and other laboratories performed in healthy volunteers and type 1 DM have demonstrated that hypoglycemia can produce a spectrum of pro-inflammatory and pro-atherothrombotic changes. Novel preliminary data from my lab has also demonstrated that hypoglycemia can impair endothelial function, reduce fibrinolytic balance (increase plasminogen activator inhibitor-1) and produce pro-atherothrombotic (increase platelet aggregation, thrombin anti-thrombin complexes, vascular adhesion molecules) changes in type 2 DM. Additionally, preliminary data presented below will demonstrate that a 90 minute episode of hypoglycemia (50 mg/dl) produces similar pro-atherothrombotic changes as compared to 4 hours of hyperglycemia (200 mg/dl). However, as investigators are just beginning to realize the effects of hypoglycemia on vascular biology, there remain many unanswered questions. For example, in the vulnerable type 2 DM population what is the dose response of different levels of hypoglycemia with attendant ANS activation on endothelial function and atherothrombotic balance? How does level of glycemic control affect ANS and vascular biologic responses to hypoglycemia in type 2 DM? Proposed studies in this protocol will provide novel information answering the clinically important question regarding the effects of mild to moderate hypoglycemia on vascular biologic mechanisms in a healthy population.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
32

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Early Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • Maryland
      • Baltimore, Maryland, United States, 21201
        • Recruiting
        • University of Maryland, Baltimore
        • Principal Investigator:
          • Stephen N Davis, MBBS
        • Contact:
          • Maka Siamashvili, MD
          • Phone Number: 410-706-5623
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 55 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

• Body mass index >21kg · m-2

Exclusion Criteria:

  • Pregnant women
  • Subjects unwilling or unable to comply with approved contraception measures
  • Subjects unable to give voluntary informed consent
  • Subjects on anticoagulant drugs, anemic or with known bleeding diatheses
  • Subjects with a history of severe, uncontrolled hypertension, heart disease, cerebrovascular incidents
  • Current tobacco use
  • Subjects with any known allergies to any of the study medications being used

Physical Exam Exclusion Criteria

  • Uncontrolled severe hypertension (i.e., blood pressure greater than 160/100)
  • Clinically significant cardiac abnormalities (e.g. heart failure, arrhythmia)
  • Pneumonia treatment or hospitalization within 2 weeks prior to enrollment (study visit)
  • Hepatic failure / jaundice
  • Renal failure
  • Cerebrovascular accident occurrence or hospitalization within 4 weeks prior to enrollment
  • Fever greater than 38.0 degrees C

Screening Laboratory Tests Exclusion Criteria

  • Hematocrit lower than 32 %
  • White blood cell (WBC) count lower than 3 thou/ul or greater than 14 thou/ul
  • Liver function tests: serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) greater than twice upper limit of normal range
  • Alkaline phosphatase greater than 150U/L
  • Total bilirubin (TBil) greater than 2 mg/dl
  • Estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2
  • Positive human immunodeficiency virus (HIV), Hepatitis B or Hepatitis C
  • Any abnormal cardiac response during multi-stage exercise test (if over 40 years of age)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: 90 mg/dl glucose clamp
Glucose clamp intervention of 90 mg/dl maintained for 90 minutes.
Device: Glucose clamp
Different levels of hypoglycemia
Experimental: 70 mg/dl glucose clamp
Glucose clamp intervention of 70 mg/dl maintained for 90 minutes.
Device: Glucose clamp
Different levels of hypoglycemia
Experimental: 60 mg/dl glucose clamp
Glucose clamp intervention of 60 mg/dl maintained for 90 minutes.
Device: Glucose clamp
Different levels of hypoglycemia
Experimental: 50 mg/dl glucose clamp
Glucose clamp intervention of 50 mg/dl maintained for 90 minutes.
Device: Glucose clamp
Different levels of hypoglycemia

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Flow mediated vasodilation of brachial artery measurements (mean maximum % change)
Time Frame: 120 minutes (pre) clamp and 240 minutes (post) clamp
baseline (pre) measurements compared to end of clamp (post) measurements
120 minutes (pre) clamp and 240 minutes (post) clamp

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Maryland, Baltimore

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Vanderbilt University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 1, 2015

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 1, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
May 8, 2015

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 14, 2015

First Posted (Estimated)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
May 15, 2015

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 7, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 5, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 00064405

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Hypoglycemia

Clinical Trials on Glucose clamp

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings