| Objective:The incidence rate of diabetes are increasing year by year.Now it is a global public health problem.Although currently there are many kinds of hypoglycemic drugs,metformin is still the most widely used hypoglycemic drug.However,recent studies have indicated that long-term use of metformin in patients with type 2 diabetes can lead to vitamin B12insufficiency or even deficiency,which may increase the risk of diabetic peripheral neuropathy.Therefore,whether to supplement vitamin B12while using metformin to treat diabetes has become a puzzle for clinicians.The purpose of this study was to explore the effect of long-term application of metformin on diabetic peripheral neuropathy through the analysis of relevant research results in recent years.Methods:Pub Med,EMBASE,Cochrane,CNKI and Wanfang databases were searched.The search deadline was November 2020,and the languages were Chinese and English.Two reviewers completed the literature retrieval and data extraction according to the established literature retrieval strategy.Relative risk(RR)was used to express the association strength.95%confidence interval(95%CI)was used as the effect scale.I~2statistics and Cochrane Q test was used to evaluate heterogeneity:I~2≥50%,or P value of Q test<0.1,indicating heterogeneity,random effect model was used,otherwise,fixed effect model was used for statistical analysis.Subgroup analysis was performed according to the main diagnostic methods of diabetic peripheral neuropathy to explore the relationship between metformin and peripheral neuropathy,the results were expressed in the form of forest chart.Egger’s test was used to evaluate publication bias,when P>0.05,there was no publication bias,On the contrary,it exists.Result:A total of 11 eligible articles were included,which includes2910 patients with type 2 diabetes,(1945 patients in the experimental group and 965 patients in the control group respectively).The results showed that metformin was not associated with diabetic peripheral neuropathy(Z=1.27,P=0.2>0.05).Long term use of metformin in patients with type 2 diabetes did not increase the risk of diabetic peripheral neuropathy(RR=1.14,95%CI:0.93-1.41).The heterogeneity of Toronto clinical scoring system(TCSS),nerve conduction velocity(NCV)and vibrating perception threshold(VPT)was lower than that between groups,the selection of DPN inspection methods will greatly affect the results of meta-analysis,there was no publication bias.Conclusion:Long term use of metformin is not associated with the risk of diabetic peripheral neuropathy in patients with type 2 diabetes.We suggest that patients with diabetes who take metformin for a long time should not worry too much or replace the use of metformin,routine monitoring of vitamin B12 and timely supplement treatment should be carried out,and clinicians should be encouraged to use objective examination such as neuroelectrophysiology to define diabetic peripheral neuropathy. |
