Validation of a Predictive Model for Diabetic Retinopathy Progression in Type-2 Diabetic Patients With Mild NPDR

Abstract

Purpose: : To validate a predictive model [Lobo et al., Arch Ophthalmol. 2004; 122:211-7] for diabetic retinopathy progression in type-2 diabetic patients with mild NPDR using non-invasive examinations.

Methods: : Four-hundred and twelve type-2 diabetic patients with mild NPDR were included in this 2-years observational and prospective study.One hundred forty-seven patients completed the first 6-month of follow-up and underwent: color fundus photography, retinal thickness (RT) measurements and blood tests.Microaneurysm formation rate (MAFR) was computed from color fundus photographs using a new method that assists graders on earmarking. Increased RT maps (Stratus OCT, Zeiss Meditec, Dubli, CA, USA) were computed using proprietary software. Patients were classified into one of the 3 phenotypes of DR progression: Phenotype 1 - low MAFR and normal RT; Phenotype 2 - low MAFR and increased RT and; Phenotype 3 - high MAFR.

Results: : Fifty-three (36.0%), 47 (32.0%) and 47 (32.0%) patients were classified respectively in Phenotypes 1, 2 and 3.Two patients classified as Phenotype 2 and 3 patients as Phenotype 3 (higher risk of progression groups) developed clinically significant macular edema after the first 6-month follow-up period.

Conclusions: : Our preliminary data confirms the existence of 3 different phenotypes of DR progression, as previously proposed, and simultaneously shows a similar distribution although using a different population.

Clinical Trial: : www.clinicaltrials.gov NCT00763802

Keywords: retina • diabetic retinopathy • imaging/image analysis: clinical