Figure 1.

Response to hypoglycaemia in diabetic patients.

Notes: Physiological responses to hypoglycaemia include increased secretion of the counterregulatory hormones glucagon, epinephrine, cortisol, and growth hormone. These mechanisms account for physiological defense mechanisms. However, the counterregulatory hormone response often blunts over time in individuals with T1DM. Besides, circulating insulin levels are entirely dependent to the administered dose, individual factors, and pharmacokinetic characteristics of exogenously administered insulin types, therefore, do not decrease as they do in patients with normal pancreatic beta-cell function. These patients also have impaired glucagon and sympathoadrenal response to hypoglycaemia, which is associated with lack of adrenergic symptoms. Hence, patients may experience severe neuroglycopenic symptoms with no preceding internal alerts. This results in the disappearance of both the first and second lines of defense against hypoglycaemia, making diabetic individuals more prone to more frequent and severe hypoglycaemia. Data from Cryer.³³