Abstract
Purpose: :
To test a predictive model for retinopathy progression in patients with diabetes type-2 using non-invasive examinations.
Methods: :
Four-hundred and twelve type-2 diabetic patients with mild non-proliferative diabetic retinopathy (NPDR) were included in this 2-years observational and prospective study.Three hundred seventy-six patients completed the first 6-month of follow-up and underwent: color fundus photography, retinal thickness (RT) measurements and blood tests. Patients were followed until they develop clinically significant macular edema (CSME) or until the 24-month examination.Microaneurysm (MA) Turnover (Formation + Disappearance rates) was computed from color fundus photographs using the RetmarkerDR (Critical Health). RT maps (Stratus OCT, Zeiss) were computed using proprietary software.Patients were classified based on the initial 6-months period by MA Turnover (≥ 9), maximal RT increase (≥ 10% than normal RT) and increased macular area RT (≥ 5% of the central 1500 micr. in diameter area) into one of the 3 phenotypes of DR progression:- Phenotype 1: low MA Turnover and no RT increase;- Phenotype 2: low MA Turnover and increased RT and;- Phenotype 3: high MA Turnover.
Results: :
One hundred and fifty six (44.8%), 97 (27.9%) and 95 (27.3%) patients were classified respectively in Phenotypes 1, 2 and 3.Three patients classified as Phenotype 1, 12 classified as Phenotype 2 and 19 patients classified as Phenotype 3 developed CSME (P<0.001). Patients classified as Phenotypes 2 and 3 presents a higher risk for CSME development than patients classified as Phenotype 1 (for Phenotype 2 OR=7.219 and for Phenotype 3 OR=12.771; P<0.001).
Conclusions: :
This study shows that it is possible to identify three different phenotypes of mild NPDR using non-invasive examinations being these phenotypes predictive CSME development.
Clinical Trial: :
http://www.clinicaltrials.gov NCT01228981
Keywords: diabetic retinopathy • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology