Investigation on the Usefulness of Serum Sorbitol and Vascular Endothelial Growth Factor A in Predicting Diabetic Retinopathy as Compared to Optical Coherence Tomography

This study was conducted to investigate the validity of serum sorbitol and Vascular Endothelial
Growth Factor A (VEGF-A) in diagnosing DR and differentiating it from diabetes without retinopathy
(DNR). A cross-sectional study included 164 diabetes mellitus patients: 30 patients with no
retinopathy (the control group), 86 patients with non-proliferative diabetic retinopathy (NPDR), and 48
patients with Proliferative Diabetic Retinopathy (PDR). Patients were referred to the Layla Qasim
Diabetic Center between November 2016 and October 2017 and an ophthalmologist established a DR
diagnosis using OCT. Serum sorbitol and serum VEGF-A were measured for all patients. By using
study biomarkers, the cut-off values of VEGF-A (124.7 ng/ml) and sorbitol (0.3112 mg/ml) were
established, and their validity parameters. For VEGF-A, the specificity was 73.1 the sensitivity was 80
and 76.2% of the observed agreement. The combined parallel test was applied as negative if both the
tests were negative or as positive if either of the tests was positive: a highly significant statistical
agreement (Kappa test p<0.001) was found with the gold standard diagnosis (OCT), with 85.4% of
observed agreement. A combination of serum sorbitol and VEGF-A for diagnosing DR and for
differentiating DR from DNR patients exhibits a significant agreement with an OCT diagnosis.