Effect of Glucose on Ocular Blood Flow

This study has been completed.
Sponsor:
Information provided by:
University Hospital, Basel, Switzerland
ClinicalTrials.gov Identifier:
NCT00350129
First received: July 7, 2006
Last updated: September 25, 2008
Last verified: September 2008
  Purpose

The primary objective is to assess the effect of glucose on retinal vascular diameter in otherwise healthy vasospastic subjects compared to non-vasospastic controls.

The secondary objective is to compare the effect of glucose also on choroidal blood flow in otherwise healthy vasospastic subjects with non-vasospastic controls.


Condition
Coronary Vasospasm

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Influence of Plasma Glucose Levels on Retinal Vascular Diameter and Choroidal Blood Flow in Vasospastic Subjects

Resource links provided by NLM:


Further study details as provided by University Hospital, Basel, Switzerland:

Enrollment: 24
Study Start Date: December 2002
Study Completion Date: February 2003
Primary Completion Date: February 2003 (Final data collection date for primary outcome measure)
Groups/Cohorts
1
healthy vasospastic subjects
2
healthy non-vasospastic subjects

Detailed Description:

It is known that a glucose load can induce an increase in ocular blood flow. Acute hyperglycemia increases retinal vessel diameters in animals and humans. The purpose of this study is to compare the effect of glucose on the ocular blood flow in vasospastics and nonvasospastics. Body core temperature depends on basal metabolism. Peripheral vasoconstriction is a physiological way to preserve core temperature of the body. The etiology of primary vasospastic syndrome is unknown and potentially represents simply a reaction to a defective metabolism. Based on this hypothesis, vasospastics are expected to show a different vascular reaction to glucose.

On both study days, after an overnight fast, the subjects will be seated for 30 minutes in the Lab and local tropicamide will be applied for pupil dilatation. After stabilisation of blood pressure Retinal vessel diameter and choroidal blood flow will be assessed. Baseline blood glucose levels will be measured. Afterwards study substance (75 gram of Glucose or Aspartate) will be applied in 3 dl of water. One and a half hour later, the vascular measurements will be repeated. Ath the end of hemodynamic assessments, blood sugar level will be measured again.

  Eligibility

Ages Eligible for Study:   18 Years to 85 Years
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population

healthy vasospastic subjects, healthy non-vasospastic subjects

Criteria

Inclusion Criteria:

  • No history of the following problems: ocular or systemic disease; chronic or current systemic or topical medication; or of drug or alcohol abuse
  • normal blood pressure (100-140 / 60-90 mmhg)
  • best corrected visual acuity above 20/25 in both eyes
  • no pathological findings upon a slit-lamp examination and indirect fundoscopy
  • ametropia within -3 to +3 diopters of spherical equivalent
  • less than 1 diopter astigmatism
  • IOP < 20 mmHg in both eyes
  • Subjects will be classified as vasospastic if they relate a clear history of frequent cold hands (answering yes to the questions: "do you have always cold hands, even during summer time?" and "do other people tell you that you have cold hands?") and as normals if they deny such a history
  • Vasospastic propensity will also be assessed by capillaroscopy

Exclusion Criteria:

  • Subjects describing "sometimes cold hands"
  • if the test substance cannot be ingested
  • not obtainable ocular blood flow measurements
  • abnormally high levels of glucose at any point in time
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00350129

Locations
Switzerland
University Hospital Basel, Eye Clinic
Basel, BS, Switzerland, 4031
Sponsors and Collaborators
University Hospital, Basel, Switzerland
Investigators
Study Director: Selim Orgül, MD University Hospital, Basel, Switzerland
  More Information

No publications provided

Responsible Party: Selim Orgul, University Hospital, Basel, Switzerland
ClinicalTrials.gov Identifier: NCT00350129     History of Changes
Other Study ID Numbers: 005-ZAC-2004-002
Study First Received: July 7, 2006
Last Updated: September 25, 2008
Health Authority: Switzerland: Swissmedic

Keywords provided by University Hospital, Basel, Switzerland:
glucose
vasospasm
RVA
LDF
vasospastic subjects
non-vasospastic subjects

Additional relevant MeSH terms:
Coronary Vasospasm
Coronary Disease
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Vascular Diseases

ClinicalTrials.gov processed this record on April 17, 2014