Abstract: Objective To analyze the dynamics of fasting glucagon (FGLC) and glucagon /insulin (FGLC/FINS) ratio with diabetes durations and their correlations with glycemic control in patients with type 2 diabetes. Methods Two hundred and sixty-two patients with type 2 diabetes were enrolled and divided into five groups according to diabetes duration: <5 years (group A, n=65); ≥ 5 years and <10 years (group B, n=62); ≥10 years and <15 years (group C, n=46); ≥15 years and <20 years (group D, n=45);≥20 years (group E, n=44). FGLC, fasting insulin (FINS), FGLC/FINS ratio, C peptide, HOMA-IR, HOMA-β and other metabolic indicators were measured to explore their correlations with diabetes duration, fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c). Results FGLC levels of groups A, B and C increased progressively with diabetes duration(r=0.243, P<0.05). Oppositely, FGLC levels of groups D and E were lower than that of group C (P<0.05) and were not correlated with diabetes duration. FGLC/FINS ratio was positively correlated with diabetes duration (r=0.243, P<0.05). Multiple stepwise regression analysis showed that the FGLC/FINS ratio was positively correlated with FBG and HbA1c (t=4.474 or 2.212, P<0.05). Conclusion FGLC of patients with type 2 diabetes increased with diabetes duration forthe first 15 years since being diagnosed, then slightly decreased, whereas the FGLC/FINS ratio consistently increased with diabetes duration. The FGLC/FINS ratio might significantly affect the glycemic control in patients with type 2 diabetes.

Key words: Type 2 diabetes, Glucagon, Glucagon/insulin ratio, Duration