Choroidal Thickness Assessed By Swept Source Optical Coherence Tomography In Patients With Diabetes

PurposeTo measure choroidal thickness (CT) in diabetic subjects and to correlate it to the severity of diabetic retinopathy (DR) and diabetic macular edema (DME).MethodsProspective study using swept-source optical coherence tomography. Choroidal thickness maps of 117 eyes of 60 diabetic patients were compared to 45 eyes of 24 healthy controls. The type of DR (no retinopathy: n = 18 eyes; non proliferative DR – NPDR: n = 62 eyes, proliferative DR – PDR: n = 37 eyes), the type of DME (no DME: n = 39 eyes, diffuse: n = 36 eyes, cystoid: n = 36 eyes, mixed: n = 6 eyes), the duration of diabetes, blood hemoglobin A1C (HbA1C) level and hypertension (HT) were recorded, and their relation to CT was evaluated using multiple regression models.ResultsNo significant difference in central subfoveal and mean overall CT was observed between diabetic patients and controls (p u003e 0.05). A significantly thinner choroid was measured in PDR eyes compared to NPDR group (p   0.05). Analysing the whole cohort, the decrease of CT was assessed in subjects with HT (p u003c 0.05). Aging showed significant correlation with choroidal thinning (30 μm/10 years; p u003c 0.001) after adjustment for HbA1C level and HT. In diabetic patients the duration of the disease significantly correlated with choroidal thinning (15 μm/10 years; p u003c 0.05) after adjusting for the effect of age, HbA1C level and HT.ConclusionsThe thinning of the choroid is affected more significantly by the age and HT, than the presence of diabetes. In diabetic patients the duration of the disease is an independent predictor of choroidal thinning.