The Effect of Amlodipine and Lisinopril on Retinal Autoregulation in Type 1 Diabetes
Information source: University of Aarhus
ClinicalTrials.gov processed this data on August 23, 2015 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Type 1 Diabetes; Diabetic Retinopathy; Eye Diseases; Diabetes Complications
Intervention: Amlodipine (Drug); Lisinopril (Drug)
Phase: N/A
Status: Completed
Sponsored by: University of Aarhus Official(s) and/or principal investigator(s): Toke Bek, MD, PhD, Principal Investigator, Affiliation: Aarhus university hospital, Dep. of ophthalmology Per L Poulsen, MD, PhD, Principal Investigator, Affiliation: Aarhus University hospital, Dep. of endocrinology (M)
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.
Clinical Details
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.
Study design: Allocation: Randomized, Endpoint Classification: Pharmacodynamics Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary outcome: Vessel diameter changes in arbitrary units as measured with the Retinal Vessel Analyzer
Secondary outcome: Blood pressure (mmHG)24 hour ambulatory blood pressure (mmHg)
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.
Eligibility
Minimum age: 18 Years.
Maximum age: 35 Years.
Gender(s): Both.
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
Locations and Contacts
Aarhus university hospital, Aarhus 8000, Denmark
Additional Information
Starting date: July 2006
Last updated: June 22, 2009
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