Purpose: Alterations in retinal oxygen metabolism and hemodynamics are signs of impending diabetic retinopathy (DR) . The study aimed to investigate risk factors of the retinal oxygen metabolism and hemodynamics for non-proliferative DR (NPDR) .
Method: The study included 166 eyes from 50 age-matched healthy subjects, 80 diabetic patients without DR (Non-DR) , and 36 NPDR. Each subjects underwent basic medical history and dilated fundal examinations including colour fundus photography, and custom-built multimodal ophthalmic device with function of retinal oximetry and laser speckle flowgraphy. Retinal metabolism was evaluated by retinal arteriolar (SO2a) , and venular (SO2v) oxygen saturation, while retinal hemodynamics was evaluated by related parameters such as diastolic duration, flow acceleration index (FAI) and resistance index (RI) . Continuous variables were analyzed by one-way analysis of variance, and categorical variables were analyzed by the chi-square test for three groups. The logistic regression model was used to obtain the risk factors of Non-DR developing into NPDR.
Result: The SO2a and SO2v of NPDR and Non-DR were higher significantly than controls (p<0.05) . There were significant difference among three groups in hemodynamics parameters, including diastolic duration, FAI, blowout score, and RI. The greatest risk factors of Non-DR developing into NPDR descending order were higher RI (odds ratio (OR) =5.84, 95% confidence interval (CI) =1.32-25.78) , shorter diastolic duration (OR= 3.46, 95% CI=1.35-8.87) , higher glycosylated hemoglobin A1c (OR=1.82, 95% CI=1.15-2.88) , lower body mass index (OR=1.74, 95% CI=1.19-2.55) , longer duration of diabetic mellitus (OR=1.21, 95% CI=1.05-1.39) , smaller age (OR=1.17, 95% CI=1.04-1.32) , higher SO2v (OR=1.16, 95% CI=1.00-1.34) , higher systolic blood pressure (OR=1.05, 95% CI=1.00-1.10) .
Conclusion: Both NPDR and Non-DR show abnormality in retinal oxygen metabolism and hemodynamics. Diastolic duration, RI, and SO2v are independent risk factors in NPDR.
Z. Jin: None. C. Zhou: None. Q. Ren: None. Z. Zhou: None. B. Zhang: None. F. Wang: None. J. Chen: None. D. Liao: None. Y. Lu: None. Y. Yang: None. J. Li: None.
Guangdong Basic and Applied Basic Research Foundation (2021A1515110747) .