Revisiting Hypoglycemia in Diabetes

Hypoglycemia is a common and serious complication of diabetes management. There is no uniformly accepted clinical definition of hypoglycemia. The American Diabetes Association recommends that people with diabetes consider treating hypoglycemia when the self-monitored blood glucose level is≤70 mg/dL (3.9 mmol/L). Hypoglycemia significantly affects mortality and quality of life. Normally, in people without diabetes, hypoglycemia is prevented by redundant protective counterregulatory mechanisms. These counterregulatory pathways become defective in people with type 1 diabetes and those with long-standing type 2 diabetes. Most hypoglycemic episodes in diabetes are related to the use of insulin and insulin secretagogues. The National Electronic Injury Surveillance System study in older adults found that nearly 25% of all medication-induced hospitalizations were due to insulin and oral hypoglycemic agents. The treatment of hypoglycemia depends on the severity of the event and symptoms. When the person is conscious and able to respond, a fast-acting carbohydrate is the treatment of choice. The “rule of 15” is often recommended. Severe hypoglycemia that is associated with inability to help oneself should be treated by using injectable glucagon. This paper reviews the typical signs and symptoms of hypoglycemia in diabetes and its pathophysiology, classification, prevention, and treatment.