Evaluation of OGTT in Patients With Post-pancreatitis Diabetes Mellitus for Diagnosis and Characterization

Inclusion Criteria: 1. Age 15-85 2. patients with the diagnosis of chronic pancreatitis and diabetes mellitus (exclude type 1 diabetes). 3. participants with painless chronic pancreatitis were diagnosed with diabetes within 2 years of the diagnosis of chronic pancreatitis. 4. participants with painful chronic pancreatitis were diagnosed with diabetes after the first attack of chronic pancreatitis. 5. patients with chronic pancreatitis were previously diagnosed type 2 diabetes mellitus for more than 3 years. Exclusion Criteria: 1. Participants with suspected malignant tumors of the pancreas or other sites of the body (including pancreatic cyst and Benign pancreatic tumor), or participants in the terminal stage of severe disease 2. Prior pancreatic surgery (including total pancreatectomy, pancreaticoduodenectomy, distal pancreatectomy, pancreatojejunostomy, or Frey), and prior bariatric or gastrointestinal surgery. 3. Serious mental illness, lesion of the liver (alanine aminotransferase or aspartate aminotransferase \> 3 times the upper reference limit) or kidney (eGFR\<60 mL/min/1.73 m2), pregnancy, breastfeeding or planning pregnancy, or accompanied with active liver diseases such as hepatitis B or hepatic cirrhosis. 4. Diagnosed type 1 diabetes, or other metabolic diseases that affect blood glucose 5. Using high-dose insulin preparations, or drugs affecting glucose metabolism (oral steroids, thiazide diuretics, beta-blockers, beta-agonist, nicotinic acid, immunosuppressant agents, antiretroviral drugs, and antipsychotics) 6. Acute complications of diabetes (diabetic ketoacidosis, severe hypoglycemia), severe microvascular disease (proliferative diabetic retinopathy, known diabetic nephropathy or neuropathy requiring treatment), and macrovascular disease (uncontrolled arterial hypertension, uncontrolled coronary artery disease, congestive heart failure, history of cerebrovascular event, seizure disorder, syncope, adrenal insufficiency, neurologic disease or atrial fibrillation) within the 12 months prior to enrollment. 7. Hospitalization for acute pancreatitis within the 2 months prior to enrollment or currently suffering acute inflammation. 8. Have been enrolled or currently participating in other clinical trials within the 3 months prior to enrollment. 9. Patients who refused to participate in the study