Abstract:AIM: To evaluate the relationship between serum vitamin D levels and diabetes retinopathy(DR)in patients with type 2 diabetes mellitus(T2DM).
METHODS: Totally 360 T2DM patients were chosen. Serum 25-(OH)D3 and 1,25-(OH)2D3 were measured by radioimmunoassay. All patients were divided into 3 groups according to the serum 25-(OH)D3 level quartile, group L(the lowest quartile, serum 25-(OH)D3<14.3ng/mL, n=87), group M(the middle two quartiles, serum 25-(OH)D3≥14.3ng/mL, and serum 25-(OH)D3<19.4ng/mL, n=176)and group H(the highest quartile, serum 25-(OH)D3≥19.4 ng/mL, n=89). Then the patients of group L were randomly divided into Group L1 which received routine drug treatment without VitD and Group L2 with VitD treatment. Serum and 25-(OH)D3, 1,25-(OH)2D3, calcium(Ca), phosphorus(P), Parathyroid Hormone(PTH) were measured at the experiment onset and at the end of follow-up visit. The new DR morbidity was calculated, too.
RESULTS: At the end of follow-up visit, serum 25-(OH)D3,1,25-(OH)2D3 and Ca levels in Group H, M, L1 were all decreased compared with their own levels at the experiment onset(P<0.05), and serum P and PTH levels were increased(P<0.05). The above indexes disorder get improved in Group L2 at the end of follow-up visit(P<0.05). The lower serum 25-(OH)D3 level, the higher DR morbidity(Group H, M, L1 13.48%, 21.59%, 45.45% respectively, P<0.05), Once Vitamin D treatment, the DR morbidity get decreased(18.6% vs 45.45%, P<0.05).
CONCLUSION: Serum 25-(OH)D3 level is an risk factor of T2DM morbidity, and vitamin D treatment can reduce the DR morbidity in type 2 diabetic patients.