ABSTRACT
Objective To study the effect of sitagliptin on insulin resistance and glucose variability in elderly patients with type 2 diabetes mellitus(T2DM) requiring high-dose insulin therapy.Methods A total of 100 elderly patients with T2DM failing to reach the standard application of large-dose insulin(＞60 U/d) treatment for three months or more [glycosylated hemoglobin (HbA1c) ＞8.0％] was randomly divided into sitagliptin group and pioglitazone group.Patients in sitagliptin group(50 cases) were treated with sitagliptin for oral use,100 mg each time,once a day,and patients in pioglitazone group(50 cases) were treated with pioglitazone for oral use,15 mg each time,once a day.The insulin dose was adjusted according to the blood glucose level in the two groups.Two groups were treated for 12 weeks.The indicators in both groups were compared,including fasting blood glucose (FBG),2 hours postprandial glucose (2hPG),glycosylated hemoglobin (HbA1c),24 hours glucose area under the curve (AUC),blood glucose coefficient of variation (CV),fasting C-peptide (FCP),2 hours postprandial C-peptide (2hPCP),fasting glucagon (FGG),2 hours postprandial glucagon(2 hFGG),cholesterol (TC),triglyceride (TG),systolic blood pressure (SBP),diastolic blood pressure(DBP),blood uric acid(BUA),daily insulin dosage(DID),body mass index(BMI),incidence of hypoglycemia and drug adverse reactions.Results After 12 weeks of treatment,the levels of FPG,2hPG,HbA1c,AUC,CV,FGG,2hFGG,TC,TG,SBP,DBP,DID and BMI in the sitagliptin group were significantly decreased than those before treatment(P＜0.05 or P＜0.01);The levels of FPG,2hPG,H bA1c,AUC,CV and BUA in the pioglitazone group were significantly decreased than those before treatment (P＜ 0.0 5 or P＜ 0.01);Compared with the pioglitazone group,the levels of 2 hPG,HbA1c,AUC,CV,FGG,2 hFGG,TC,TG,SBP,DBP,DID and BMI were significantly decreased in the sitagliptin group(all P＜0.05),and the levels of FCP and 2hPCP in the sitagliptin group were higher than those in the pioglitazone group(all P＜0.01).The incidence of hypoglycemia in the sitagliptin group was lower than that in the pioglitazone group(x2 =4.039,P =0.045).The incidence of adverse reactions in the sitagliptin group was lower than that in the pioglitazone grouP(x2 =3.979,P=0.043).Conclusion Sitagliptin combined with insulin is better than insulin combined with pioglitazone in elderly patients with T2DM requiring the application of high-dose insulin therapy,and the combining treatment could decrease insulin resistance,insulin dosage and the incidence of hypoglycemia.