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

Study Overview
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Brief Summary
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To evaluate the islet function and insulin secretion pattern of post-pancreatitis diabetes mellitus by oral glucose tolerance testing, and to explore the pathophysiological characteristics of PPDM-C which provide evidence for the diagnosis of PPDM-C.

Detailed Description
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Blood samples will be collected from patients with chronic pancreatitis by oral glucose tolerance test (steamed bun meal test, SBMT) to assess their pancreatic islet function and insulin secretion pattern, measure other intestinal hormones, exosomes, plasma metabolites, and serum biochemical factors to characterize the pathophysiological features of PPDM-C and provide evidence for the diagnosis of PPDM-C. In order to better understand the glycemic fluctuations in patients with chronic pancreatitis combined with diabetes and guide subsequent treatment, Continuous Glucose Monitoring would be used in patients with chronic pancreatitis who had new-onset diabetes or poor glycemic control.

Official Title
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Evaluation of Oral Glucose Tolerance Testing in Patients With Post-pancreatitis Diabetes Mellitus for Diagnosis and Characterization: a Cross-sectional Trial

Conditions
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Chronic Pancreatitis, Pancreatogenic Type 3C Diabetes Mellitus, Diabetes Mellitus, Oral Glucose Tolerance Test

Intervention / Treatment
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* Diagnostic Test: blood test
* Device: Continuous Glucose Monitor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 15-85 patients with the diagnosis of chronic pancreatitis and diabetes mellitus (exclude type 1 diabetes). participants with painless chronic pancreatitis were diagnosed with diabetes within 2 years of the diagnosis of chronic pancreatitis. participants with painful chronic pancreatitis were diagnosed with diabetes after the first attack of chronic pancreatitis. patients with chronic pancreatitis were previously diagnosed type 2 diabetes mellitus for more than 3 years. Exclusion Criteria: 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 Prior pancreatic surgery (including total pancreatectomy, pancreaticoduodenectomy, distal pancreatectomy, pancreatojejunostomy, or Frey), and prior bariatric or gastrointestinal surgery. 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. Diagnosed type 1 diabetes, or other metabolic diseases that affect blood glucose 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) 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. Hospitalization for acute pancreatitis within the 2 months prior to enrollment or currently suffering acute inflammation. Have been enrolled or currently participating in other clinical trials within the 3 months prior to enrollment. Patients who refused to participate in the study

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| CP<br>patients with chronic pancreatitis but not combined with diabetes | Diagnostic Test: blood test<br>* Evaluation of islets function and insulin secretion pattern： Evaluating the venous plasma glucose, c-peptide, and insulin concentrations at 0h, 0.5h, 1h, 2h, and 3h after the SBMT in patients with chronic pancreatitis. Characterization of pathophysiological features： Measuring intestinal hormones, exosomes, serum metabolites, and serum biochemical factors<br>|
| PPDM-C<br>patients with post-chronic pancreatitis diabetes mellitus | Diagnostic Test: blood test<br>* Evaluation of islets function and insulin secretion pattern： Evaluating the venous plasma glucose, c-peptide, and insulin concentrations at 0h, 0.5h, 1h, 2h, and 3h after the SBMT in patients with chronic pancreatitis. Characterization of pathophysiological features： Measuring intestinal hormones, exosomes, serum metabolites, and serum biochemical factors<br>Device: Continuous Glucose Monitor<br>* blood glucose will be monitored 24 hours a day from 7 to 14 days by wearing continuous glucose monitor(only for patients who had new-onset diabetes or poor glycemic control )<br>|
| CP+IGT<br>patients with chronic pancreatitis combined with impaired glucose tolerance | Diagnostic Test: blood test<br>* Evaluation of islets function and insulin secretion pattern： Evaluating the venous plasma glucose, c-peptide, and insulin concentrations at 0h, 0.5h, 1h, 2h, and 3h after the SBMT in patients with chronic pancreatitis. Characterization of pathophysiological features： Measuring intestinal hormones, exosomes, serum metabolites, and serum biochemical factors<br>Device: Continuous Glucose Monitor<br>* blood glucose will be monitored 24 hours a day from 7 to 14 days by wearing continuous glucose monitor(only for patients who had new-onset diabetes or poor glycemic control )<br>|
| CP+T2DM<br>patients with chronic pancreatitis combined with type 2 diabetes mellitus | Diagnostic Test: blood test<br>* Evaluation of islets function and insulin secretion pattern： Evaluating the venous plasma glucose, c-peptide, and insulin concentrations at 0h, 0.5h, 1h, 2h, and 3h after the SBMT in patients with chronic pancreatitis. Characterization of pathophysiological features： Measuring intestinal hormones, exosomes, serum metabolites, and serum biochemical factors<br>Device: Continuous Glucose Monitor<br>* blood glucose will be monitored 24 hours a day from 7 to 14 days by wearing continuous glucose monitor(only for patients who had new-onset diabetes or poor glycemic control )<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| steamed bun meal test result 1 | Levels of glucose under the steamed bun meal experiment (100g flour made steamed bun) | Within 5 hours after the end of the steamed bread meal test | 
| steamed bun meal test result 2 | Levels of c-peptide bun meal experiment (100g flour made steamed bun) | Within 6 hours after the end of the steamed bread meal test | 
| steamed bun meal test result 3 | Levels of insulin under the steamed bun meal experiment (100g flour made steamed bun) | Within 7 hours after the end of the steamed bread meal test | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| gut hormone | Levels of gut hormone under the steamed bun meal experiment (100g flour made steamed bun) | up to 1 month | 
| Continuous glucose monitor results | Time to target range (TIR) : the proportion of time with blood glucose fluctuation | after using continuous glucose monitor device for 7-14 days | 
| glycemic control | glycosylated hemoglobin（%） | at the time of enrollment |