Changes in early optical coherence tomography angiography among children and adolescents with type 1 diabetes: Relation to fibroblast growth factor 21

Aims: Current diagnostic and treatment modalities target late stages of diabetic retinopathy (DR) when retinopathy has already been established. Novel and more sensitive strategies are needed. Optical coherence tomography angiography (OCTA) permits non-invasive visualisation of retinal microcirculation. Fibroblast growth factor-21 (FGF21) plays an important role in glucose and lipid homoeostasis. This study assesses early OCTA changes among children and adolescents with type 1 diabetes (T1DM) compared to fundus photography and correlates them to diabetes-duration, glycaemic control, and FGF21; hence, it determines their value in early detection of DR.

Methodology: Hundred children and adolescents with T1DM were assessed for diabetes-duration, insulin therapy, hypoglycemia, and diabetic-ketoacidosis frequency, Tanner staging, glycated-haemoglobin (HbA1c), fasting lipids, urinary albumin/creatinine ratio, and serum FGF21. OCTA and fundus photography were done for the studied patients and 100 age, gender, and Tanner matched healthy controls.

Results: The mean age of the children and adolescents with T1DM was 10.84 years, their mean diabetes-duration was 3.27 years and their median FGF21 was 150 pg/ml. FGF21 was significantly higher among children and adolescents with T1DM than controls (p < 0.001). Children and adolescents with T1DM had a significantly larger foveal avascular zone (FAZ) and lower peripapillary and inside-disc capillary densities (p < 0.05); with no significant fundus photography difference (p = 0.155) than controls. FAZ was positively correlated and peripapillary and inside-disc capillary densities were negatively correlated with diabetes-duration, HbA1c, FGF21, and Tanner stage. FGF21 was significantly higher in T1DM children and adolescents having OCTA changes compared to those with normal OCTA (p = 0.002). Multivariate-regression revealed that FAZ is independently associated with diabetes-duration, HbA1c and FGF21.

Conclusions: OCTA changes start early in children and adolescents with T1DM long before the fundus changes. These changes are correlated with diabetes-duration, puberty, glycaemic, and FGF21.