The Relationship Between Stage of Diabetic Retinopathy and Retinal Blood Flow in Patients With IDDM During Euglycemic Clamp

Diabetes Mellitus, Type 1 Clinical Trial

Official title:

The Relationship Between Stage of Diabetic Retinopathy and Retinal Blood Flow in Patients With IDDM During Euglycemic Clamp

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00814008
• Other study ID #: OPHT-181298
• Status: Completed
• Phase: Phase 2
• First received: December 22, 2008
• Last updated: December 22, 2008
• Start date: March 1999
• Est. completion date: December 2003

Study information

• Verified date: December 2008
• Source: Medical University of Vienna
• Contact: n/a
• Is FDA regulated: No
• Health authority: Austria: Agency for Health and Food Safety
• Study type: Interventional

Clinical Trial Summary

Impaired retinal blood flow has been implicated in the pathogenesis of diabetic retinopathy. Patel et al. (1992) showed that retinal blood flow increases with the level of diabetic retinopathy. Grunwald et al. (1996) reported that patients with insulin dependent diabetes mellitus (IDDM) of relatively short duration have increased retinal blood flow, even before the onset of diabetic retinopathy. On the other hand the data of Bursell et al. (1996) indicate that IDDM patients have reduced retinal blood flow, when they have normal blood glucose levels, but this study may have considerable methodological limitations. Acute elevations of blood glucose levels, however, result in an increase in retinal blood flow (Grunwald et al. 1987, Bursell et al. 1996). Based on previous experimental data the investigators hypothesize that ocular blood flow is increased in early diabetes and reduced at later stages of the disease. Previous studies have demonstrated that metabolic conditions such as hyperglycemia influence outcome parameters and thereby might have confounded results regarding ocular blood flow in diabetic retinopathy. The investigators will therefore study patients with IDDM during euglycemic conditions.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 64
• Est. completion date: December 2003
• Est. primary completion date: April 2000
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 19 Years and older

Eligibility

Inclusion Criteria:

Patients with IDDM:

• Age >= 19 years

• Best corrected visual acuity >= 0.8

• Ametropia < 6 dpt

Healthy control subjects:

• Age and sex matched to the subjects in the patients group

• Best corrected visual acuity >= 0.8

• Ametropia < 6 dpt

Exclusion Criteria:

Any of the following will exclude a diabetic patient from the study:

• Presence of intraocular pathology other than diabetic retinopathy (for example:

cataract, glaucoma, ocular hypertension)

• Hypertension (Systolic blood pressure > 160 mm Hg or diastolic blood pressure > 90 mm Hg)

• Previous laser photocoagulation treatment

• Pregnancy (in women)

Any of the following will exclude a healthy subject from the study:

• Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study

• Treatment in the previous 3 weeks with any drug

• Symptoms of a clinically relevant illness in the 3 weeks before the first study day

• History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with distribution, metabolism or excretion of study drugs

• Blood donation during the previous 3 weeks

• Pregnancy (in women)

Study Design

Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Diagnostic

Related Conditions & MeSH terms

• Diabetes Mellitus, Type 1
• Diabetic Retinopathy
• Insulin
• Regional Blood Flow
• Retina

Intervention

Drug:
• Insulin
Insulin Dosage form : intravenous infusion, infusion period 60 minutes Dosage: continuous dose of 0.5 mU/kg/min infused intravenously over 60 min; Insulin Lilly, Huminsulin, Lilly, Fegersheim, France
• Glucose
Glucose: Dosage form : intravenous infusion, infusion period 60 minutes per dose level Dosage: at a rate to maintain blood glucose level at 100mg ; 20mg/100ml Glucose

Locations

Country	Name	City	State
Austria	Department of Clinical Pharmacology, Medical University of Vienna	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Medical University of Vienna

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	retinal blood flow after 1 hour of insulin clamp		2 x 2 minutes	No
Secondary	Mean blood velocities in ophthalmic artery, posterior ciliary arteries and central retinal artery after 1 hour of insulin clamp		2 x 10 minutes	No