Linagliptin Response to OGTT in Prediabetes and Type 2 Diabetes Mellitus

Association of Fasting GLP-1 Level With the Effect of Linagliptin After an Oral Glucose Tolerance Test in Prediabetes and Type 2 Diabetes Mellitus

There are studies that suggest glycemic response to incretin-based therapies differs between Asians and Caucasians, whereby Asians have better response compared to Caucasians. Hence, the therapeutic response could also be augmented by difference in incretin system among various ethnicities. This study is carried out to study the effect of dipeptidyl-peptidase IV (DPPIV) inhibitors in prediabetes and T2DM patients who have different levels of GLP-1 and to determine the effect on glycemic profiles, insulin resistance/sensitivity, beta-cell functon.

A 12-week, open-label, single treatment study using linagliptin is conducted in 28 prediabetes and 22 T2DM subjects who are divided into low and high fasting GLP-1 groups. Prediabetes are recruited from OGTT screening. Type 2 diabetes patients are recruited from specialised diabetes clinic and routine follow-up. A 75-g oral glucose tolerance test (OGTT) is performed at week 0 and 12. Venous blood samples were drawn at times 0 (before initiation of OGTT), 30, 60, 90, 120 min from the indwelling catheter for measurement of glucose and insulin.All prediabetes and T2DM subjects receive Linagliptin 5mg once daily for a duration of 12 weeks.

Inclusion Criteria:

• Prediabetes diagnosed from OGTT and T2DM subjects
• HbA1c > 6.5% and <10%
• Subjects not receiving any glucose-lowering medication or just receiving metformin and/or sulphonylureas and/or alpha-glucosidase inhibitors on stable dose for at least 3 months.
• Subjects who are willing to participate and sign the informed consent form

Exclusion Criteria:

• Subjects with ketoacidosis or lactic acidosis, overt diabetes, another disease causing secondary glucose intolerance, congestive heart failure (New York Heart Association Class III or IV), myocardial infarction, stroke or ischemic attacks in past 6 months, uncontrolled severe hypertension, active liver conditions such as cirrhosis or hepatitis [elevation in liver enzymes to higher activities than double the respective normal value], moderate to severe renal insufficiency, pregnancy, breast-feeding
• Patients receiving insulin, GLP-1 receptor agonists, dipeptidyl peptidase IV inhibitors or glucose-lowering medications other than metformin /sulphonylureas /alpha-glucosidase inhibitors as treatment.
• Subjects with uncontrolled blood glucose HbA1c>10%
• Subjects who plan to move out of state / country