The time course of beta cell dysfunction in chronic ethanol-induced pancreatitis: a prospective analysis.

Insulin-glucose homeostasis was examined in 62 patients with chronic pancreatitis (CP). All patients were graded on the basis of test results from five studies: (1) endoscopic retrograde cholangiopancreatography, (2) fat-stimulated release of pancreatic polypeptide (PP), (3) NBT-bentiromide PABA test, (4) 72-hour fecal fat test, and (5) oral glucose tolerance test (OGTT). Patients with CP were graded as either mild/moderate or severe by means of a scoring system that we devised and have previously reported. Nineteen patients were graded as mild/moderate and 43 patients were graded as severe. The endocrine function of non-beta and beta islet cells was compared by assessing release of PP after fat and by release of insulin during OGTT. Release of PP was depressed in 58%, and the depressed output was found in only patients with a severe grade of CP. Forty-four of 62 patients (71%) with CP had abnormal OGTT findings; the distribution of this abnormality was not greatly different between mild/moderate and severe grades. Depressed release of insulin was seen in 58% (36 of 62)--more commonly in patients with a severe grade (10%) but also in 32% of patients with a mild/moderate grade. A subset of patients with CP sustains early beta-cell dysfunction. We conclude that decreased output of PP is a more reliable measure of functional deficit and stage in CP.