| Objective:To systematically evaluate the therapeutic effects of vitamin D supplementation on the basis of conventional treatment in type 2 diabetes mellitus,and analyzed quantitatively.Methods:Databases including PubMed,The Cochrane Library,ScienceDirect Online,VIP,CNKI,WanFang Data,to collect randomized controlled trials(RCTs)about vitamin D supplementation for type 2 diabetes mellitus from inception to April 2018.Two reviewers independently screened literature,extracted data and assessed the risk of bias of included studies.Then meta-analysis was conducted by Stata12.1 softwares.Results:A total of 19 RCTs involving 1892 patients(951 patients in experimental group and 941 patients in control group)were included.The results of meta-analysis showed that,compared with the control group,the vitamin D3 supplementation group had a significant abatement in HbAlc(SMD=-0.883,95%CI:-1.342～-0.423,P<0.0001),FPG(SMD=-0.52,95%CI:-0.9～-0.14,P<0.0001).2hPG(SMD=-1.186,95%CI:-2.303～-0.07,P=0.037)、HOMA-IR(SMD=-1.5,95%CI:-2.45～-0.55,P<0.0001)and LDL-c(SMD=-0.75,95%CI:-1.26～-0.24,P=0.004).Subgroup analysis showed that,the levels of HOMA-IR were significantly decreased in the vitamin D3 supplementation group in Asian(SMD=-1.51,95%CI:-2.33～-0.69,P=0.004).The levels of FPG were significantly decreased in the vitamin D3 is administered on a daily basis and is less than 4000IU/day supplementation group(SMD=-0.6,95%CI:-0.89～-0.3,P=0.001).The levels of LDL-c were significantly decreased in the vitamin D3 supplementation group with calcium and baseline HbAlc<8%(SMD=-1.32,95%CI:-1.66～-0.99,P<0.0001;SMD=-1.06,95%CI:-1.81～-0.31,P=0.006).Conclusion:The type 2 diabetic patients treated with vitamin D3 is improved,which reveal vitamin D3 may have some therapeutic effect,but some confounding factors may exist,and the present evidence is not sufficient,further larger,high quality trials are warranted. |
