When should I consider initiating insulin therapy?

From the Guidelines

You should consider initiating insulin therapy when your patient's HbA1c remains above 7-7.5% despite maximum doses of other diabetes medications, or in cases of severe hyperglycemia, particularly when associated with weight loss or ketonuria/ketosis, as stated in the most recent guidelines 1.

Key Considerations for Insulin Therapy

• Insulin therapy is a crucial step in managing type 2 diabetes when other treatments have failed to achieve glycemic targets.
• The preferred approach is to start with basal insulin, such as Lantus, Levemir, or Tresiba, at a dose of 10 units daily or 0.1-0.2 units per kilogram of body weight, with adjustments based on blood glucose readings 1.
• Basal insulin analogues are preferred over NPH insulin due to their reduced risk of hypoglycemia, particularly nocturnal hypoglycemia 1.
• Mealtime insulin may be added if basal insulin alone does not achieve glycemic targets, especially to control postprandial glucose excursions.

Important Factors to Consider Before Initiating Insulin

• Proper education on injection technique, blood glucose monitoring, and hypoglycemia management is essential before starting insulin therapy.
• The choice of insulin regimen should be individualized based on the patient's specific needs, lifestyle, and preferences.
• Continuous monitoring of glucose levels and the use of support tools, such as apps guiding insulin dose adaptation, can be helpful in managing insulin therapy.

Recent Guidelines and Recommendations

• The 2022 consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) emphasizes the importance of not delaying insulin initiation when glycaemic targets are not met with other treatments 1.
• The report also highlights the role of GLP-1 receptor agonists as a potential alternative to insulin therapy in certain patients with type 2 diabetes.

From the FDA Drug Label

1. 3 Initiation of Insulin Glargine Therapy Recommended Starting Dosage in Patients with Type 1 Diabetes The recommended starting dosage of Insulin Glargine in patients with type 1 diabetes is approximately one-third of the total daily insulin requirements. Use short-acting, premeal insulin to satisfy the remainder of the daily insulin requirements Recommended Starting Dosage in Patients with Type 2 Diabetes The recommended starting dosage of Insulin Glargine in patients with type 2 diabetes who are not currently treated with insulin is 0.2 units/kg or up to 10 units once daily.

Initiating Insulin Therapy: Consider initiating insulin therapy in patients with type 1 diabetes when they require insulin to satisfy their daily insulin requirements, and in patients with type 2 diabetes when they are not currently treated with insulin and require improvement in glycemic control.

• Type 1 Diabetes: Initiate insulin therapy when the patient's metabolic needs and blood glucose monitoring results indicate the need for insulin.
• Type 2 Diabetes: Initiate insulin therapy when the patient's blood glucose monitoring results and glycemic control goals are not met with current treatment, and the patient is not currently treated with insulin. 2

From the Research

Initiating Insulin Therapy

Insulin therapy should be considered in the following situations:

• A diagnosis of diabetes or hyperglycemia has been confirmed 3
• Patients with type 1 diabetes mellitus (T1DM) require insulin as the primary treatment 3
• Patients with type 2 diabetes mellitus (T2DM) may require insulin therapy in cases of:
  • Acute illness or surgery 3
  • Pregnancy 3
  • Glucose toxicity 3
  • Contraindications to or failure to achieve goals with oral antidiabetic medications 3
  • Need for flexible therapy 3
• HbA1c levels are ≥ 7.5% (≥ 58 mmol/mol) in T2DM patients, and insulin is considered alone or in combination with oral agents 3
• HbA1c levels are ≥ 10% (≥ 86 mmol/mol) in T2DM patients, and insulin is essential for treatment when diet, physical activity, and other antihyperglycemic agents have been optimally used 3

Insulin Regimens

The preferred method of insulin initiation in T2DM is to begin by adding a long-acting (basal) insulin or once-daily premixed/co-formulation insulin or twice-daily premixed insulin, alone or in combination with glucagon-like peptide-1 receptor agonist (GLP-1 RA) or in combination with other oral antidiabetic drugs (OADs) 3

• Basal insulin analogs, such as insulin detemir, can be used to minimize unpredictable processes of NPH insulin and provide effective therapeutic options for patients with type 1 and type 2 diabetes 4
• Insulin detemir has been shown to be noninferior to insulin glargine in terms of glycemic control in patients with type 1 diabetes 5

Monitoring and Adjusting Insulin Therapy

Blood glucose monitoring is an integral part of effective insulin therapy and should not be omitted in the patient's care plan 3

• Fasting plasma glucose (FPG) values should be used to titrate basal insulin, whereas both FPG and postprandial glucose (PPG) values should be used to titrate mealtime insulin 3
• Insulin regimens should be adopted and individualized to closely resemble a natural physiologic state and avoid wide fluctuating glucose levels 3