Abstract
Purpose :
The oxygen saturation in the larger retinal vessels has been shown to increase with increasing retinopathy grade and to predict the effect of anti-VEGF treatment in patients with diabetic maculopathy. However, it is unknown to what extent the increased oxygen saturation covaries with other risk factors or if oxygen saturation is a risk factor in itself for the development of the disease.
Methods :
Seven hundred and twenty-two patients referred for specialist evaluation of diabetic retinopathy including retinal oximetry were studied. Using multiple regression analysis it was investigated whether the oxygen saturation in the larger retinal arterioles (Sat-A) and venules (Sat-V) were contributed to the severity of diabetic retinopathy, independently of gender, age, diabetes duration, diabetes type, body mass index (BMI), blood pressure (BP), HbA1c, visual acuity (VA) and central retinal thickness (CRT).
Results :
Diabetes duration, HbA1c, CRT and Sat-V contributed to retinopathy grade leading to both diabetic maculopathy (DME) and proliferative diabetic retinopathy (PDR), whereas gender and diabetes type contributed to retinopathy grade leading to DME and Sat-A to retinopathy grade leading to PDR. The included parameters could explain less than 15% of the variation in retinopathy grade, and retinal oxygen saturation had the same contribution to retinopathy grade as HbA1c.
Conclusions :
Retinal oxygen saturation is an independently contributing factor to the severity of diabetic retinopathy. This suggests that the retinal oxygen saturation could be added as a risk factor to programmes aimed at individualizing the control interval in diabetic retinopathy. However, there is need for prospective studies in order to confirm to what extent the retinal oxygen saturation is predictive for the development of diabetic retinopathy over time.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.