Hypoglycemia: still a risk in the elderly.

Hypoglycemia is an underappreciated and potentially fatal complication of insulin and sulfonylurea treatment of diabetes mellitus in the elderly. After several years of diabetes, patients typically lose glucagon and epinephrine responses to hypoglycemia, resulting in loss of adrenergic warning symptoms, as well as prolongation of hypoglycemic episodes. Also of pertinence to the elderly, renal disease, liver disease, congestive heart failure, hypothyroidism, hypoadrenalism, medications, and inadequate monitoring may also contribute to hypoglycemia. The benefits of tight control can be observed only if it is applied to appropriately selected patients.