Study Stopped
not enough subjects recruited
Coupling of Neural Activity and Retinal Blood Flow in Diabetes
1 other identifier
observational
1
1 country
1
Brief Summary
The prevalence of diabetes is increasing and the management of the disease is nowadays considered a major challenge. Affected patients have increased mortality and morbidity as well as a significant drop in the quality of life. The complications of diabetes can be classified as microvascular (e.g. nephropathy, neuropathy or retinopathy) or macrovascular (e.g. cardiovascular or cerebrovascular). Several large-scale epidemiologic studies indicating that wider retinal venous caliber is strongly associated with the fasting glucose level as well as with diabetes. Another retinal vascular abnormality that is associated with diabetes is an abnormal retinal vascular response to flicker stimulation. Retinal vessel dilatation in response to stimulation with diffuse flicker light occurs due to a phenomenon called neurovascular coupling. This means that increased activity of neurons is associated with an increased retinal metabolism. This leads to a release of endogenous vasodilator substances and increased blood flow. However, previous studies were limited by the fact that retinal vessel diameters and blood flow were not measured simultaneously. The present study aims to investigate whether the response of retinal vessel diameters and blood flow velocities to flicker stimulation is altered in patients with diabetes. Both parameters will be measured in real time using Fourier Domain Doppler OCT.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at below P25 for all trials
Started Mar 2013
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
April 11, 2011
CompletedFirst Posted
Study publicly available on registry
June 17, 2011
CompletedStudy Start
First participant enrolled
March 6, 2013
CompletedPrimary Completion
Last participant's last visit for primary outcome
March 6, 2013
CompletedStudy Completion
Last participant's last visit for all outcomes
March 6, 2013
CompletedFebruary 20, 2020
February 1, 2020
Same day
April 11, 2011
February 19, 2020
Conditions
Outcome Measures
Primary Outcomes (2)
Retinal vessel diameters
18 months
Retinal blood flow velocities
18 months
Study Arms (2)
Diabetic retinopathy
Patients with early insulin dependent diabetes and no or mild non-proliferative retinopathy
healthy
healthy control subjects
Eligibility Criteria
24 patients with early insulin dependent diabetes and no or mild non-proliferative retinopathy, non-smokers 24 age and sex matched healthy controls, non-smokers
You may qualify if:
- Men and women aged over 18 years, nonsmokers
- Normal findings in the medical history (except diabetes) and physical examination unless the investigator considers an abnormality to be clinically irrelevant
- normal laboratory findings (except diabetes associated parameters) unless the investigator considers the abnormality to be clinically irrelevant
- normal ophthalmic findings (except mild diabetic retinopathy), Ametropia less than 6 diopters
You may not qualify if:
- Any of the following will exclude a healthy subject from the study:
- Regular use of vasoactive drugs
- Abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
- Symptoms of a clinically relevant illness in the 3 weeks before the first study day
- Blood donation during the previous 3 weeks
- History or presence of any ocular pathology
- History or family history of epilepsy
- Systemic hypertension defined as systolic blood pressure \>150mmHg, diastolic blood pressure \>90mmHg
- Pregnancy
- Any of the following will exclude a subject with diabetes from the study:
- Presence of non-insulin dependent diabetes, maturity onset diabetes of the young (MODY diabetes)
- History or presence of any other diabetes induced vascular pathologies or any other ocular condition other then diabetic retinopathy
- Best corrected visual acuity \<0.8
- Previous laser photocoagulation treatment
- Systemic hypertension defined as systolic blood pressure \>150mmHg, diastolic blood pressure \>90mmHg
- +5 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Department of Clinical Pharmacology
Vienna, 1090, Austria
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Gerhard Garhöfer, MD
Department of Clinical Pharmacology, Medical University of Vienna
Study Design
- Study Type
- observational
- Observational Model
- CASE CONTROL
- Time Perspective
- PROSPECTIVE
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Assoc. Prof. Priv. - Doz. Dr
Study Record Dates
First Submitted
April 11, 2011
First Posted
June 17, 2011
Study Start
March 6, 2013
Primary Completion
March 6, 2013
Study Completion
March 6, 2013
Last Updated
February 20, 2020
Record last verified: 2020-02