ABSTRACT
Objective To investigate the changes of visual acuity,fundus changes,and serum vitamin D concentration in diabetic retinopathy patients treated with metformin,and to evaluate its clinical efficacy.Methods Totally 80 cases (160 eyes) patients with background diabetic retinopathy were included in the study,and were divided into observation group (metformin + Pancreatic Kininogenase Enteric-coated Tablets) and control group (Pancreatic Kininogenase Enteric-coated Tablets) according to the different treatment methods used for 3 months.Fundus fluorescein angiography was used to evaluate the improvement of the fundus lesions.The serum levels of vitamin D were measured with electrochemiluminescence immunoassay (ECLIA).Results After 3 months of treatment,serum vitamin D concentration of the observation group increased,and the differences were statistically significant (P ＜ 0.05) when compared to before treatment.However,3 months after treatment,serum vitamin D levels of the control group increased slightly,but the difference was not statistically significant (P ＞ 0.05).The total effective rate of fundus improvement in the observation group and the control group was 70％ and 55％,respectively.There was significant difference between the two groups in the improvement of fundus (P ＜ O.05).Conclusions Metformin has an adjunctive effect on background diabetic retinopathy,and the increase of serum vitamin D may be one of the mechanisms of metformin in improving diabetic retinopathy.