Relationships of A1c Variability for 10 Years and Beta Cell Function at the Time of Diagnosis in Type 2 Diabetes

Abstract

Background: Recent several reports emphasized A1c variability along with average blood glucose determined by Alc. Many studies have been showing the relationship of A1c variability with chronic diabetic complications. But, associations between patterns or degrees of A1c variability and influential factors have not been studied much. Therefore, this study aimed to evaluate the relationships of A1c variability for 10 years and beta cell function at the time of diagnosis in type 2 diabetes in clinical practice. Methods: Subjects of this study were 518 newly diagnosed type 2 diabetic patients. To evaluate beta cell function, we checked fasting c-peptide, glucose, and insulin and assessed homeostasis model assessment beta cell function index (HOMA-β) and homeostasis model assessment for insulin resistance (HOMA-IR) at the time of diagnosis. A1cs, fasting plasma glucose, and lipid profile were serially measured at least once in every year for 10 years. Results: We found that higher A1c variability was associated with younger age at diagnosis of diabetes, lower BMI, higher first A1c, higher 2nd year A1c, and higher mean A1c. C-peptide and homeostasis model assessment beta cell function index were the highest in the low SD group and the lowest in high SD group. Conclusion: A1c variability for 10 years in newly diagnosed type 2 diabetes is inversely related with the marker of beta cell function at the time of diagnosis.