An analysis of the glucagon response to hypoglycaemia in patients with type 1 diabetes and in healthy subjects

Short-term fasting lowers glucagon levels under euglycemic and hypoglycemic conditions in healthy humans

Fasting is associated with increased susceptibility to hypoglycemia in people with type 1 diabetes, thereby making it a significant health risk. To date, the relationship between fasting and insulin-induced hypoglycemia has not been well characterized, so our objective was to determine whether insulin-independent factors, such as counterregulatory hormone responses, are adversely impacted by fasting in healthy control individuals. Counterregulatory responses to insulin-induced hypoglycemia were measured in 12 healthy people during 2 metabolic studies. During one study, participants ate breakfast and lunch, after which they underwent a 2-hour bout of insulin-induced hypoglycemia (FED). During the other study, participants remained fasted prior to hypoglycemia (FAST). As expected, hepatic glycogen concentrations were lower in FAST, and associated with diminished peak glucagon levels and reduced endogenous glucose production (EGP) during hypoglycemia. Accompanying lower EGP in FAST was a reduction in peripheral glucose utilization, and a resultant reduction in the amount of exogenous glucose required to maintain glycemia. These data suggest that whereas a fasting-induced lowering of glucose utilization could potentially delay the onset of insulin-induced hypoglycemia, subsequent reductions in glucagon levels and EGP are likely to encumber recovery from it. As a result of this diminished metabolic flexibility in response to fasting, susceptibility to hypoglycemia could be enhanced in patients with type 1 diabetes under similar conditions.

Minimizing morbidity of hypoglycemia in diabetes: a review of mini-dose glucagon

Type 1 diabetes is a common chronic disease of childhood and one of the most difficult conditions to manage. Advances in insulin formulations and insulin delivery devices have markedly improved the ability to achieve normal glucose homeostasis. However, hypoglycemia remains the primary limiting factor in achieving normoglycemia and is a frequent complication in children with acute gastroenteritis and/or poor oral intake. In situations of impaired carbohydrate intake or absorption, glucagon therapy is the only out-of-hospital treatment option available to families and caregivers. Glucagon is recommended for the treatment of severe hypoglycemia and rapidly increases blood glucose by increasing hepatic glucose production from glycogenolysis. Mini-dose glucagon is a widely utilized off-label treatment for managing mild or impending hypoglycemia and is administered as a small subcutaneous injection. It was initially described for use in children who were unable to tolerate or absorb oral carbohydrates but not in need of advanced medical care. Yet, mini-dose glucagon may be useful in any individual with relative insulin excess. The regimen aims to prevent severe hypoglycemic episodes and is safe, effective, and easily administered by patients and caregivers in the out-of-hospital setting. By empowering patients and their families, this important tool could help to alleviate the physical, psychosocial, and financial burden evolving from impending hypoglycemia.