Purpose:
To quantify retinal microvascular alterations using optical coherence tomography angiography in diabetic patients, and to evaluate the accuracy of decreased vessel density (VD) in predicting early diabetic retinopathy (DR).
Methods:
One hundred and two eyes of 51 diabetic patients and 92 eyes of 46 individuals without diabetes were examined. Duration of diabetes, insulin therapy, blood pressure, HbA1C, dyslipidemia, axial length, and the presence of DR were recorded. Retinal VD was measured using optical coherence tomography angiography. The effect of risk factors on VD and on DR was assessed using multivariable regression analyzes.
Results:
Compared with controls, VD was lower in diabetic patients (P < 0.05) and correlated with diabetes duration (P = 0.02). Decreased VD was associated with a higher risk of DR (odds ratio: 1.24, P = 0.009) after controlling for systemic and ocular confounding variables. Eyes with a VD of <50% had an odds ratio of 4.55 (P = 0.003) for DR and an odds ratio of 3.22 (P = 0.03) for decreased visual acuity (<20/25) after controlling for systemic and ocular confounding factors.
Conclusion:
The risk of DR and vision loss is substantially higher in eyes with lower VD, suggesting that optical coherence tomography angiography metrics may serve as prognostic biomarkers for the prediction of early onset DR.
