What is the recommended approach to initiate insulin therapy?

Initiating Insulin Therapy in Diabetes

Basal insulin alone is the most convenient initial insulin regimen, beginning at 10 units per day or 0.1-0.2 units/kg/day, depending on the degree of hyperglycemia, with individualized titration over days to weeks as needed.

Initial Insulin Selection and Dosing

• Basal insulin is the recommended first insulin choice for most patients with type 2 diabetes, typically prescribed in conjunction with metformin and sometimes one additional noninsulin agent 1
• Starting dose should be 10 units per day or 0.1-0.2 units/kg/day, based on the degree of hyperglycemia 1
• Long-acting basal analogs (U-100 glargine or detemir) can be used instead of NPH insulin to reduce the risk of symptomatic and nocturnal hypoglycemia 1
• Longer-acting basal analogs (U-300 glargine or degludec) may provide even lower hypoglycemia risk compared with U-100 glargine 1

Titration Process

• Equip patients with a self-titration algorithm based on self-monitoring of blood glucose to improve glycemic control 1
• Set a fasting plasma glucose target and choose an evidence-based titration algorithm 1
• A common approach is to increase the dose by 2 units every 3 days until the fasting glucose target is reached without hypoglycemia 1, 2
• For hypoglycemia, determine the cause and if no clear reason is found, lower the dose by 10-20% 1

Advancing Insulin Therapy

• If basal insulin has been titrated to an acceptable fasting blood glucose level but A1C remains above target, consider advancing to combination injectable therapy 1
• Before adding prandial insulin, consider adding a GLP-1 receptor agonist, which can provide complementary outcomes with less hypoglycemia and weight gain 1
• When initiating prandial insulin, start with one dose with the largest meal or the meal with the greatest postprandial glucose excursion 1
• The recommended starting dose of mealtime insulin is 4 units, 0.1 units/kg, or 10% of the basal dose 1
• If A1C is <8% when starting mealtime bolus insulin, consider decreasing the basal insulin dose 1

Special Considerations

• For patients with marked hyperglycemia (A1C >10% or blood glucose >300 mg/dL) or symptomatic hyperglycemia, consider starting with insulin therapy immediately, with or without additional agents 1
• The progressive nature of type 2 diabetes should be regularly and objectively explained to patients, avoiding the use of insulin as a threat or describing it as a sign of personal failure 1
• Comprehensive education regarding self-monitoring of blood glucose, diet, and the avoidance and treatment of hypoglycemia is critically important for any patient using insulin 1
• Monitor for clinical signals of overbasalization, including basal dose greater than 0.5 units/kg/day, high bedtime-to-morning glucose differential, or hypoglycemia 1

Insulin Regimen Intensification

• If basal insulin alone is insufficient (dose >0.5 units/kg/day with A1C still above target), progress to more complex regimens 1
• Stepwise addition of prandial insulin can be implemented, starting with one meal and adding injections as needed 1, 3
• For patients requiring multiple daily injections, consider basal-bolus therapy with basal insulin once daily and rapid-acting insulin before meals 1, 3
• Premixed insulin products containing both basal and prandial components are an alternative option but may be associated with increased hypoglycemia risk and require fixed meal schedules 1

Cost Considerations

• There have been substantial increases in insulin prices over the past decade, making cost an important consideration in insulin selection 1
• NPH insulin may be a more affordable option for some patients, though it carries a higher risk of hypoglycemia compared to analog insulins 1
• Regular assessment of financial obstacles that may impact diabetes management is an important component of effective care 1