Hypoglycemia in Diabetes

Background

• Hypoglycemia is a common acute complication in patients with diabetes that may lead to hospitalization, morbidity, and death.
  • Iatrogenic hypoglycemia (also known as treatment-associated hypoglycemia) is the main limiting factor in achieving optimal glycemic control in diabetes.
  • Preventing hypoglycemia is a critical component of diabetes management.
  • Hypoglycemia typically occurs in patients treated with insulin or an insulin secretagogue (such as sulfonylureas or meglitinide).
• Any patient experiencing recurrent hypoglycemia may develop hypoglycemia unawareness.
  • Hypoglycemia unawareness is characterized by the reduction or absence of the autonomic symptoms that normally occur with hypoglycemia (such as palpitations, tremor, and hunger) and may be associated with a lower glucose threshold for development of these symptoms.
  • The first sign of hypoglycemia in a patient with hypoglycemia unawareness may be confusion, requiring the assistance of others to recognize and treat the hypoglycemic episode.
  • Hypoglycemia unawareness can severely compromise strict diabetes control and quality of life and is reported to increase risk of episodes of severe hypoglycemia.
• Severe hypoglycemia can cause cardiac arrhythmia and may progress to seizure, loss of consciousness, and coma.

Evaluation

• Hypoglycemia is diagnosed in patients with diabetes when the measured plasma glucose level decreases to a point where it may cause harm to the individual or others (typically at a glucose level < 70 mg/dL [3.9 mmol/L]), with or without the presence of symptoms.
• Hypoglycemia is classified into 3 levels based on blood glucose level and clinical correlates.

Table 1. Classification of Levels of Hypoglycemia

Management

• Acute treatment of hypoglycemia in diabetes in the outpatient setting:
  • If the patient is conscious, give glucose 15-20 g orally.
    • Pure glucose is preferred (for example, glucose tablets), although any glucose-containing carbohydrate is acceptable.
      • Advise patient to avoid using carbohydrate source with added fat (such as chocolate candy), since the added fat may slow glucose absorption and prolong time to glycemic recovery.
      • Advise patients with type 2 diabetes to avoid use of protein-rich carbohydrate sources (such as milk) for treating hypoglycemia because ingested protein may increase insulin response without increasing plasma glucose.
    • Check the blood glucose after 15 minutes and repeat the treatment if hypoglycemia persists.
    • Advise patient to consume a meal or snack once blood glucose monitoring or glucose pattern is trending up to prevent hypoglycemia recurrence if ongoing insulin activity or treated with an insulin secretagogue.
  • If the patient is unable or unwilling to take glucose orally, give glucagon for treatment of hypoglycemia.
    • Administer glucagon preparations that do not have to be reconstituted (such as preparations delivered by intranasal route or those using autoinjectors with stable glucagon) over preparations that do need to be reconstituted in outpatients with severe hypoglycemia (Strong recommendation).
    • Glucagon therapy must be followed by administration of oral carbohydrates to prevent recurrence of hypoglycemia.

Table 2: Comparison of Glucagon Formulations

• In the inpatient setting, dextrose IV is the preferred treatment for hypoglycemia if patient is unable to take oral glucose or another carbohydrate-containing food or beverage. Give dextrose 25 g IV bolus in adults, 10% dextrose 2-4 mL/kg IV bolus in children, followed by a continuous infusion until the patient is able to eat.
• Follow-up after a hypoglycemic event:
  • Prescribe a glucagon preparation that does not have to be reconstituted to all patients treated with insulin or an insulin secretagogue and instruct family members, coworkers, friends, school personnel, and others on its use.
  • Instruct patients to carry carbohydrates at all times to treat hypoglycemia.
  • Provide a structured program of patient education instead of giving unstructured advice to all outpatients with diabetes treated with insulin or an insulin secretagogue to avoid repeated hypoglycemia (Strong recommendation). Key elements of the program include understanding optimal treatments for hypoglycemia and improving patient's ability to recognize subtle hypoglycemia symptoms.
  • Advise patients to wear medical alert identification.
• Prevention of recurrent hypoglycemia in patients with hypoglycemia unawareness:
  • Provide hypoglycemia avoidance education and reevaluate treatment goals and regimen for any patient with hypoglycemia unawareness or ≥ 1 episode of level 3 hypoglycemia.
  • Raise glycemic targets for at least several weeks to partially reverse hypoglycemia unawareness in patients treated with insulin who experience hypoglycemia unawareness, ≥ 1 episode of level 3 hypoglycemia, or a pattern of unexplained level 2 hypoglycemia (Strong recommendation).
  • Use a continuous glucose monitor to provide an early warning system to alert the patient of impending hypoglycemia.