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Retinal Blood Flow and Microthrombi in Type 1 Diabetes

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ClinicalTrials.gov Identifier: NCT00406991
Recruitment Status : Completed
First Posted : December 4, 2006
Last Update Posted : October 30, 2015
Sponsor:
Information provided by:
Massachusetts Eye and Ear Infirmary

Brief Summary:

The project aims to find mechanisms for the abnormal retinal blood flow that in diabetic patients often precedes any evidence of clinical retinopathy and may contribute to the development of retinopathy.

Specifically, the projects tests the hypothesis that reduced retinal blood flow found in young patients with type 1 diabetes reflects increased resistance in the small vessels of the retina caused by the formation of small blood clots, called microthrombi; and that antiplatelet agents normalize the reduced retinal blood flow.


Condition or disease Intervention/treatment Phase
Diabetes Diabetic Retinopathy Drug: aspirin Drug: clopidogrel Phase 2

Detailed Description:

The ultimate goal of this research is to contribute to the development of strategies to prevent diabetic retinopathy. This project will test the hypothesis that antiplatelet agents normalize the reduced blood flow observed early in the course of type 1 diabetes. If the hypothesis is proven correct, the results will indicate that the formation of small blood clots (microthrombi) occurs early in diabetic retinal vessels. In turn, because microthrombosis could readily account for the occlusive microangiopathy that causes the sight-threatening stages of diabetic retinopathy, the results will propose the desirability of antiplatelet therapy for the prevention of diabetic retinopathy.

We have three specific aims:

  1. To confirm that, under basal conditions, retinal blood flow measured with the laser Doppler method in a group of type 1 diabetic patients with no or minimal retinopathy differs from the flow measured in age- and sex-matched nondiabetic control subjects;
  2. To determine whether the response of retinal blood flow to low-dose aspirin (81 mg/day) administered for 2 months versus placebo, differs between type 1 diabetic patients with no or minimal retinopathy and age- and sex-matched nondiabetic control subjects;
  3. To determine whether in type 1 diabetic patients with no or minimal retinopathy the response of retinal blood flow to low-dose aspirin differs from the response to clopidogrel, a drug that interferes with platelet function downstream of the site of aspirin action.

Study Type : Interventional  (Clinical Trial)
Enrollment : 100 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double
Primary Purpose: Diagnostic
Official Title: Retinal Blood Flow and Microthrombi in Type 1 Diabetes
Study Start Date : June 2003
Study Completion Date : March 2006

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Diabetes Type 1
U.S. FDA Resources




Primary Outcome Measures :
  1. Retinal blood flow

Secondary Outcome Measures :
  1. Retinal arterial blood speed
  2. Retinal arterial diameter


Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Age 18-45 years,
  • type 1 diabetes duration 1-15 years,
  • absent or minimal retinopathy (EDTRS 20).
  • Age- and gender-matched healthy controls

Exclusion Criteria:

  • smoking,
  • systemic diseases other than diabetes,
  • retinal diseases other than diabetic retinopathy,
  • pregnancy,
  • bleeding disorders,
  • aspirin allergy,
  • use of anti-platelet agents,
  • non-steroidal anti-inflammatory agents,
  • angiotensin converting enzyme inhibitors,
  • angiotensin receptor antagonists,
  • Vitamin E in large doses.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00406991


Locations
United States, Massachusetts
Schepens Eye Research Institute
Boston, Massachusetts, United States, 02114
Sponsors and Collaborators
Schepens Eye Research Institute
Investigators
Principal Investigator: Mara Lorenzi, MD Schepens Eye Research Institute

ClinicalTrials.gov Identifier: NCT00406991     History of Changes
Other Study ID Numbers: 2002-015
2003P-000224
EY014812
First Posted: December 4, 2006    Key Record Dates
Last Update Posted: October 30, 2015
Last Verified: March 2006

Keywords provided by Massachusetts Eye and Ear Infirmary:
retinal blood flow
diabetic retinopathy
microthrombosis
aspirin
clopidogrel

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 1
Retinal Diseases
Diabetic Retinopathy
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Autoimmune Diseases
Immune System Diseases
Eye Diseases
Diabetic Angiopathies
Vascular Diseases
Cardiovascular Diseases
Diabetes Complications
Aspirin
Clopidogrel
Anti-Inflammatory Agents, Non-Steroidal
Analgesics, Non-Narcotic
Analgesics
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Inflammatory Agents
Antirheumatic Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Cyclooxygenase Inhibitors
Enzyme Inhibitors