The Effect of Amlodipine and Lisinopril on Retinal Autoregulation in Type 1 Diabetes

NCT ID: NCT00337298

Last Updated: 2009-06-23

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 25 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2006-07-31
• Study Completion Date: 2009-02-28

Brief Summary

The purpose of this study is to compare the effect of two antihypertensive drugs on retinal vessel diameter in young type 1 diabetics. The retinal vessel analyzer (RVA) was used to investigate how the drugs affected vessel diameter, when the subjects were exposed to an increase in blood pressure, induced by isometric muscle contraction and when they were stimulated by flickering light.

Detailed Description

Diabetes is a leading cause of blindness in the western part of the world. Diabetic patients develop diabetic retinopathy which can progress to blindness. Diabetic retinopathy is associated with an increase of blood flow in the retinal vessels, ischaemia in the periphery and macular oedema. It has been shown in previous trials, that the pressure and metabolic autoregulation is disturbed in patients with diabetes, and it is believed to contribute to the development of diabetic retinopathy.

In healthy subjects the retinal arterioles will contract during an increase in blood pressure, but trials have shown that this response is impaired in diabetics. When the retina is exposed to flickering lights, the metabolism increase and the arterioles in healthy subjects dilates. In diabetics this dilation is impaired. In this trial we want to investigate if an ACE-inhibitor (lisinopril) or calcium channel blocker (amlodipine) influence this response in subjects exposed to increased blood pressure vs increased retinal metabolism.

Conditions

Type 1 Diabetes; Diabetic Retinopathy; Eye Diseases; Diabetes Complications

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Blinding Strategy: QUADRUPLE

Study Groups

1

Crossover design. Arm is same all the way

Group Type: EXPERIMENTAL

Amlodipine

Intervention Type: DRUG

1 (5mg) tablet daily, given 14 days totally before measure of outcome.

Lisinopril

Intervention Type: DRUG

Lisinopril 10 mg given daily for 14 days and then outcome was measured.

Interventions

Amlodipine

1 (5mg) tablet daily, given 14 days totally before measure of outcome.

Intervention Type: DRUG

Lisinopril

Lisinopril 10 mg given daily for 14 days and then outcome was measured.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• Type 1 diabetes
• 18-35 years of age
• Simplex retinopathy at last screening (Less than 10 retinal haemorrhages at the nearest ordinary screening examination)
• normotensive (BP not above 160 mmHg systolic or 100 mmHg diastolic)

Exclusion Criteria

• Pregnancy
• Systolic Bloodpressure above 160 mmHg
• Diastolic bloodpressure above 100 mmHg
• Retinopathy grade higher than simplex retinopathy
• Prior retinal laser photocoagulation

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 35 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Velux Fonden

OTHER

Sponsor Role: collaborator

University of Aarhus

OTHER

Sponsor Role: lead

Responsible Party

Aarhus University Hospital

Principal Investigators

Toke Bek, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Aarhus university hospital, Dep. of ophthalmology

Per L Poulsen, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Aarhus University hospital, Dep. of endocrinology (M)

Locations

Aarhus university hospital

Aarhus, , Denmark

Countries

Denmark

Other Identifiers

Jmehl01

Identifier Type: -

Identifier Source: org_study_id