The Effect of Dopamine on Diabetic Retinopathy
Dopamine DR
1 other identifier
interventional
60
1 country
1
Brief Summary
The purpose of this study is to evaluate the use of electroretinogram (ERG) using a novel handheld system, RETeval, and evaluate contrast sensitivity testing in detecting pre-clinical retinopathy on a tablet device. Investigators also seek to assess if a medication called Sinemet™ CR can improve the electrical functions of the eye in participants with diabetes mellitus. This study will include a total of 45 participants; 30 with diabetes mellitus and 15 age-matched non-diabetic controls. Participants with diabetes mellitus and electroretinogram (ERG) delays will be randomized to a low or high dose Sinemet CR group.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_1 diabetes
Started Jan 2016
Longer than P75 for phase_1 diabetes
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
Study Start
First participant enrolled
January 1, 2016
CompletedFirst Submitted
Initial submission to the registry
March 4, 2016
CompletedFirst Posted
Study publicly available on registry
March 11, 2016
CompletedPrimary Completion
Last participant's last visit for primary outcome
August 15, 2019
CompletedStudy Completion
Last participant's last visit for all outcomes
August 15, 2019
CompletedOctober 9, 2019
October 1, 2019
3.6 years
March 4, 2016
October 7, 2019
Conditions
Keywords
Outcome Measures
Primary Outcomes (4)
Change in Retinal Function assessed by Electroretinogram (ERG) Device
The RETeval device consists of a hand-held wand with a pupil tracker. A skin electrode placed below the eye or DTL fiber records the response to flash stimuli. The pupil tracker provides feedback to the system so that the flash stimuli can compensate for the pupil size and produce the proper illumination to the retina. RETeval is intended to generate photopic signals and measure and display the electrical response signals generated by the retina and the visual nervous system using flash stimuli.
Baseline, Week 4
Change in Contrast Sensitivity assessed by the Contrast Sensitivity Function v1.0 (CSF v1.0) Tablet Application
Participants will view the screen monocularly while wearing their normal correction. A drifting grating will be presented at 60 cm for 3, 6, 12 and 18 c/d. Following photopic testing (100 lux), the participant will be dark-adapted and a neutral density filter will be applied to the tablet screen to produce luminance of \~1 lux.
Baseline, Week 4
Change in Contrast Sensitivity assessed by the Sine Wave Grafting Test (CSV-1000E)
The CSV-1000E is self-illuminated (85 cd/m2). A drifting grating will be presented at 60 cm for 3, 6, 12 and 18 c/d. The participant will view the chart from 2.5m. The intensity of the CSV-1000 will be reduced to 1 lux with neutral density filters for scotopic testing.
Baseline, Week 4
Change in Visual Acuity assessed by the Standard Snellen Static Chart
The common Snellen chart is printed with eleven lines of block letters. The first line consists of one very large letter, which may be one of several letters, for example E, H, or N. Subsequent rows have increasing numbers of letters that decrease in size. Participants will cover one eye from 6 metres or 20 feet away, and read aloud the letters of each row, beginning at the top. The smallest row that can be read accurately indicates the visual acuity in that specific eye. The test will be repeated covering the opposite eye.
Baseline, Week 4
Study Arms (4)
Diabetes Group - Low Dose Sinemet CR
EXPERIMENTALParticipants with diabetes mellitus type-2 and electroretinogram (ERG) delays will receive low dose Sinemet CR twice daily for two weeks.
Diabetes Group - High Dose Sinemet CR
EXPERIMENTALParticipants with diabetes mellitus type-2 and electroretinogram (ERG) delays will receive high dose Sinemet CR twice daily for two weeks.
Diabetes Group - No Electroretinogram (ERG) Delays
OTHERParticipants with diabetes mellitus type-2 who do not have electroretinogram (ERG) delays. Participants in this group will have one baseline visit only.
Age-Matched Controls
OTHERParticipants will serve as age-matched controls for participants with diabetes. This group will participate in the baseline, week 2, and week 4 visits only.
Interventions
Sinemet CR (25 mg carbidopa/100 mg levodopa) will be taken by mouth twice daily for two weeks.
Sinemet CR (50 mg carbidopa/200 mg levodopa) will be taken by mouth twice daily for two weeks.
ERG testing consists of sitting in the dark for 15 minutes. During the procedure, participants will have a single-use adhesive sensor strip placed on the skin near the eye. A hand-held device, called the RETeval, will be placed in front of the eye and a series of flashes and flickering lights presented. The light intensity level is typically not uncomfortable. When right eye imaging is complete, the procedure will be repeated on the left eye. Both eyes will be evaluated in less than 5 minutes for most participants. Electroretinogram (ERG) testing will be completed at baseline, day 1, week 2, and week 4.
Contrast sensitivity testing consists of looking at a series of moving lines on a tablet device. The lines will change from white to grey to black. Participants will be asked to determine when they can no longer distinguish between the lines. Contrast sensitivity testing will be completed at baseline, day 1, week 2, and week 4.
Participants will be asked to look at an eye chart with letters or symbols that become smaller as they move from top to bottom of the chart. Visual acuity testing will be completed at baseline, day 1, week 2, and week 4.
Eligibility Criteria
You may qualify if:
- Participants with Diabetes Mellitus:
- Diagnosis of diabetes mellitus type-2
- HbA1c between 8 and 12%
- Age-Matched Controls:
- Non-diabetic
You may not qualify if:
- Participants with Diabetes Mellitus:
- Currently taking dopamine-enhancing drugs (L-DOPA, bromocriptine)
- Currently taking nonselective monoamine oxidase (MAO) inhibitors
- Diagnosis of psychosis, Parkinson's disease, restless leg syndrome, major depression, confounding ocular disease (eg. visually significant cataract, glaucoma, macular degeneration, or retinitis pigmentosa)
- Pregnancy
- Age-Matched Controls:
- Diabetes diagnosis
- Currently taking dopamine-enhancing drugs (L-DOPA, bromocriptine)
- Currently taking nonselective monoamine oxidase (MAO) inhibitors
- Diagnosis of psychosis, Parkinson's disease, restless leg syndrome, major depression, confounding ocular disease (eg. visually significant cataract, glaucoma, macular degeneration, or retinitis pigmentosa)
- Pregnancy
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Emory Universitylead
Study Sites (1)
Atlanta VA Medical Center
Atlanta, Georgia, 30033, United States
Related Publications (1)
Motz CT, Chesler KC, Allen RS, Bales KL, Mees LM, Feola AJ, Maa AY, Olson DE, Thule PM, Iuvone PM, Hendrick AM, Pardue MT. Novel Detection and Restorative Levodopa Treatment for Preclinical Diabetic Retinopathy. Diabetes. 2020 Jul;69(7):1518-1527. doi: 10.2337/db19-0869. Epub 2020 Feb 12.
PMID: 32051147DERIVED
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Machelle Pardue, PhD
Emory University
Study Design
- Study Type
- interventional
- Phase
- phase 1
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Adjunct Professor
Study Record Dates
First Submitted
March 4, 2016
First Posted
March 11, 2016
Study Start
January 1, 2016
Primary Completion
August 15, 2019
Study Completion
August 15, 2019
Last Updated
October 9, 2019
Record last verified: 2019-10