Unravelling the heterogeneity of diabetes in chronic pancreatitis: Alpha and beta cell dysfunction and association with glycaemic control

AbstractAimsDiabetes in patients with chronic pancreatitis is a heterogeneous condition with some patients presenting with pre‐existing diabetes and others developing diabetes after pancreatitis onset. We aimed to characterise beta and alpha cell function in these patients and examine differences between those with and without pre‐existing diabetes.MethodsWe included 26 patients with chronic pancreatitis and insulin‐treated diabetes, divided into two subgroups: 13 with pre‐pancreatitis diabetes (having type 2 diabetes before their chronic pancreatitis diagnosis) and 13 with post‐pancreatitis diabetes. Patients underwent comprehensive clinical characterisation, including an arginine stimulation test to measure fasting and stimulated levels of C‐peptide and glucagon. Additionally, they were monitored with continuous glucose monitoring over 20 days.ResultsPatients with chronic pancreatitis and diabetes exhibited reduced fasting and stimulated C‐peptide and glucagon responses to arginine, though responses varied considerably among individuals. Post‐pancreatitis diabetes patients had lower glucagon responses than those with pre‐pancreatitis diabetes (mean difference −19.3 pmol/L, 95% confidence interval (CI) −35.6 to −3.0). However, C‐peptide levels were similar between the groups. Pre‐pancreatitis diabetes patients spent more time in level 2 hyperglycaemia compared to post‐pancreatitis patients (12.9% vs. 6.7%, p = 0.02). In contrast, post‐pancreatitis diabetes patients had more time in both level 1 and level 2 hypoglycaemia (p = 0.03 and p = 0.05, respectively). A low glucagon response was correlated with time spent in hypoglycaemia (Rho = −0.54, p < 0.01).ConclusionsDiabetes in chronic pancreatitis is a heterogeneous entity. The presence of type 2 diabetes prior to chronic pancreatitis is associated with a reduced risk of alpha cell dysfunction and hypoglycaemia.