Islet cell dysfunction in patients with chronic pancreatitis

Table 1 Summary of the studies that assessed glucagon response in chronic pancreatitis

Ref.	Population characteristics	Method used	Key findings
Mumme et al[12], 2017	(1) Patients with diabetes due to CP; (2) Patients with type 2 diabetes without CP; and (3) NGT patients without CP	(1) OGTT; (2) Hyperinsulinemic, stepwise hypoglycemic clamp	(1) Higher fasting glucagon levels and an initial rise of glucagon after the OGTT in both groups with diabetes compared to the healthy group; and (2) Lower glucagon levels in both groups with diabetes after hypoglycemia in the clamp study
Kumar et al[14], 2018	Chronic calcific pancreatitis: pre- and post-Frey's procedure	OGTT	Before surgery: Elevated glucagon level at 60- and 120-min post OGTT compared to the fasting state
Lundberg et al[11], 2016	Non-diabetic patients with CP and healthy controls	(1) MMTT; and (2) FSIVGTT	(1) Elevated glucagon levels (total area under curve) in CP patients at both basal and post-stimulation state; and (2) No difference in basal to peak increment glucagon levels between the groups
Knop et al[38], 2010	(1) CP patients with NGT; (2) CP patients with IGT; (3) CP patients with DM; and (4) Normal healthy controls	(1) OGTT; and (2) IVGTT	(1) Similar fasting mean glucagon in all the groups; (2) During OGTT: No increase in glucagon level in the CP + NGT group; increased glucagon up to 60 min in the CP + IGT and CP + DM groups; a small early rise in glucagon which was suppressed later in the healthy group; and (3) During FSIVGTT, AUC for glucagon was higher in the CP + DM group compared to normal controls
Larsen et al[6], 1988	(1) Type 1 diabetes; (2) Insulin dependent diabetes secondary to CP; and (3) Normal healthy controls	(1) IV Glucagon; (2) IV Arginine infusion; and (3) Mixed meal test	No difference in baseline glucagon or stimulated glucagon levels between the groups with diabetes
Kannan et al[8], 1979	CP patients and healthy control group	(1) 50 g OGTT; and (2) L-arginine stimulation	(1) Elevated basal fasting glucagon and higher glucagon levels during the OGTT in CP patients compared to controls; and (2) An early rise in glucagon after L-arginine stimulation in CP patients compared to normal patients
Donowitz et al[10], 1975	CP group and healthy control group	IV L-alanine infusion	(1) Lower basal glucagon levels in CP patients; and (2) No rise in glucagon level after alanine stimulation in CP patients compared to normal controls

AUC: Area under curve; CP: Chronic pancreatitis; DM: Diabetes mellitus; FSIVGTT: Frequently sampled intravenous glucose tolerance test; IGT: Impaired glucose tolerance; IV: Intravenous; IVGTT: Intravenous glucose tolerance test; MMTT: Mixed meal tolerance test; NGT: Normal glucose tolerance; OGTT: Oral glucose tolerance test.