The Hemoglobin Glycation Index Correlates With Efficacy Of Metformin Therapy In Individuals Newly Diagnosed With Type 2 Diabetes Mellitus

Introduction: Metformin is a cornerstone of glucose-lowering therapy in type 2 diabetes mellitus (T2DM). Biologic variations in glucose metabolism, as reflected by the hemoglobin glycation index (HGI), may influence the therapeutic effect of this medication. This study examined the correlation between HGI and efficacy of metformin in individuals newly diagnosed with T2DM. Method: This observational study enrolled 328 individuals with new onset T2DM between December 2013 and November 2015. Participants exceeded 21 years of age and had received metformin for at least 12 months after diagnosis. Individuals who received antidiabetic medications in addition to metformin were excluded. Efficacy of metformin was compared between equally sized subgroups stratified by baseline HGI. Result: All participants attained glycemic improvement after metformin therapy, with enhanced efficacy in individuals with high HGI after adjusting for pretreatment glycemic status. Differences in therapeutic effect between HGI subgroups were maintained after one year of treatment. Even among people with comparable pretreatment hemoglobin A1c, the high HGI subgroup also demonstrated better clinical response to metformin therapy. Conclusion: HGI correlated with efficacy of metformin therapy in individuals with T2DM. Glycemic improvement was enhanced in participants with high HGI at diagnosis, for whom additional antidiabetic medications may be unnecessary. HGI is a promising guide for personalized glycemic treatment in individuals with new onset T2DM.