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

Type 1 Diabetes Clinical Trial

Official title:

Lack of Effect of Antihypertensive Treatment With Amlodipine and Lisinopril on Retinal Autoregulation in Patients With Type 1 Diabetes and Mild Diabetic Retinopathy. A Prospective Randomized Clinical Trial.

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00337298
• Other study ID #: Jmehl01
• Status: Completed
• Phase: N/A
• First received: June 14, 2006
• Last updated: June 22, 2009
• Start date: July 2006
• Est. completion date: February 2009

Study information

• Verified date: June 2009
• Source: University of Aarhus
• Contact: n/a
• Is FDA regulated: No
• Health authority: Denmark: Danish Medicines Agency
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 25
• Est. completion date: February 2009
• Est. primary completion date: February 2009
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 35 Years

Eligibility

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

Study Design

Allocation: Randomized, Endpoint Classification: Pharmacodynamics Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)

Related Conditions & MeSH terms

• Diabetes Complications
• Diabetes Mellitus
• Diabetes Mellitus, Type 1
• Diabetic Retinopathy
• Eye Diseases
• Retinal Diseases
• Type 1 Diabetes

Intervention

Drug:
• Amlodipine
1 (5mg) tablet daily, given 14 days totally before measure of outcome.
• Lisinopril
Lisinopril 10 mg given daily for 14 days and then outcome was measured.

Locations

Country	Name	City	State
Denmark	Aarhus university hospital	Aarhus

Sponsors (2)

Lead Sponsor	Collaborator
University of Aarhus	Velux Fonden

Country where clinical trial is conducted

Denmark, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Vessel diameter changes in arbitrary units as measured with the Retinal Vessel Analyzer		120,240,360,480,600,720 and at 840secs	No
Secondary	Blood pressure (mmHG)		120,240,360,600,720,840 secs	No
Secondary	24 hour ambulatory blood pressure (mmHg)		24 hours	No