Abstract
Purpose:
Baseline data of the EUROCONDOR Project (EC-FP7-278040) to assess neurovascular changes and the efficacy of neuroprotective drugs administered topically to prevent or arrest diabetic retinopathy (DR).
Methods:
450 type 2 diabetic patients, 194 with no DR (ETDRS level < 20) and 256 with mild non-proliferative DR (NPDR - ETDRS levels 20 or 35) were included in a 2-year interventional clinical trial to assess functional abnormalities related to neurodegeneration and the efficacy of neuroprotective drugs administered topically to prevent or arrest DR. Patients were recruited in 11 clinical sites in the European Vision Institute Clinical Research Network (EVICR.net). The study started in February 2013 and recruitment was completed in November 2013. Five visits are planned at months 0, 6, 12, 18 and 24, including best corrected visual acuity (BCVA), multifocal electroretinography (mfERG), colour fundus photography (CFP) for ETDRS classification and microaneurysm (MA) turnover using RetmarkerDR®, and spectral domain optical coherence tomography (SD-OCT). Centralised reading of mfERG, ETDRS, MA turnover and SD-OCT is performed by the Coimbra Ophthlamology Reading Centre (CORC). A normative database of 110 patients was established to evaluate mfERG implicit time Z-scores. One eye per patient is selected by the Reading Centre as the study eye.
Results:
450 patients were included (65.6% males) with ages ranging from 45 to 75 years. The mean systolic and diastolic blood pressure was, respectively, 135.1 ± 14.7 and 77.2 ± 10.1 mmHg. Eyes/patients showed at baseline a mean number of MA of 0.7 ± 1.3 and a mean BCVA of 83.7 ± 10.3 ETDRS letters. HbA1C was significantly increased in NPDR patients (7.27 ± 1.05 % vs, 6.95 ± 0.86 %; p=0.001). Comparing mean central subfield retinal thickness (RT) with normal values, 2.8 % of the eyes/patients showed an abnormally decreased RT and 1.4% an abnormally increased RT.
Conclusions:
mfERG, RT and MA registered at baseline indicate varying involvement of the different components of the neurovascular unit. The results obtained in the baseline data analysis will contribute to identify correlations between DR initial neurodegenerative and microvascular changes.
Keywords: 499 diabetic retinopathy •
615 neuroprotection •
688 retina