方法：选取本院内分泌科门诊及住院的T2DM患者360例，测定其血清25-(OH)D₃水平，并根据其四分位数将患者分为三组，血清25-(OH)D₃水平3、1，25-(OH)₂D₃、钙、磷、甲状旁腺素(PTH)等水平变化。

结果：H，M，L1组患者随访结束时其血清25-(OH)D₃、1，25-(OH)₂D₃、钙水平明显下降(P<0.05)，血清磷、PTH水平上升(P<0.05)。L2组患者以上指标的紊乱明显减轻(P<0.05)。且H，M，L1组患者DR发病率依次增高(13.48%，21.59%，45.45%，P<0.05)，而L2组患者DR发生率较L1组明显降低(18.6% vs 45.45%，P<0.05)。

结论：相对低下血清维生素D水平的T2DM患者伴随较高的糖尿病视网膜病变发生率，骨化三醇治疗可以降低T2DM患者新发糖尿病视网膜病变的发生。

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.