To investigate the effect of exenatide on serum insulin and plasma glucose in obese subjects with impaired glucose regulation(IGR).

A total of 75 obese subjects with IGR were enrolled from May 2011 to November 2012 in Quanzhou First Hospital Affiliated Fujian Medical University. A total of 62 eligible subjects were divided into the hyperinsulinemia group (HIns, fasting serum insulin ≥15 mU/L and(or)2-hour serum insulin ≥80 mU/L post glucose load, n=32) and the non-hyperinsulinemia group (NHIns, n=30) by the serum insulin level. Fasting and 2h plasma glucose in OGTT, insulin , C-peptide and body weight were measured at the baseline, D5 and D14 of exenatide treatment. Insulin resistance was evaluated by the homeostasis model assessment (HOMA-IR) and the gutt insulin sensitivity index. Paired t test was used to test within group change. One-way ANOVA was applied to compare differences of continuous variables between subgroups. Rates were compared by using the χ² test.

Compared with the baseline, fasting and 2 h glucose significantly improved at D5 in the two groups, but without further decrease at D14 in the two groups(t=4.42, 9.78, 4.00, 8.66 with all P<0.05). Compared with the baseline, the fasting insulin significantly decreased at D5 in the HIns group(t=2.07, P<0.05). The 2 h insulin level significantly decreased at D5 with further reduction at D14 in the HIns group(F=24.17, P<0.05). No significant decrease was observed with the fasting and 2 h insulin in the NHIns group at D5 and D14. HOMA-IR significantly decreased at D5 in the HIns groups(t=3.27, P<0.05), while showed no change at D5 and D14 in the NHIns group(all P>0.05). Gutt insulin sensitivity index increased at D5 in the HIns groups(t=-9.84, P<0.05)with further increase at D14(F=55.96, P<0.05). Compared with the baseline, the Gutt insulin sensitivity index significantly increased at D5 in the NHIns group(t=-4.27, P<0.05). Body weight significantly decreased in the HIns group and the NHIns group at D14(t=14.13, 12.00, all P<0.05), while showed no change at D5 in both groups. None of the subjects withdrew because of adverse event including hypoglycemia.

Exenatide short-term treatment in obese subjects with IGR can benefit glucose regulation, improve insulin resistance and control body weight.

Exenatide; Obesity; Impaired glucose regulation; Hyperinsulinism