Management of Type 2 Diabetes with Insulin Therapy

Introduction to Insulin Therapy

For patients with type 2 diabetes on an insufficient insulin regimen, the combination of basal insulin with a GLP-1 receptor agonist is the preferred strategy due to its higher efficacy, durability of therapeutic effect, and benefits in weight and hypoglycemia, as recommended by the American Diabetes Association 1

The first option for patients with type 2 diabetes is basal insulin plus GLP-1 RA, which offers greater potency for reducing glycemia, less weight gain, lower risk of hypoglycemia compared to intensified insulin regimens, and greater durability of therapeutic effect, according to the American College of Clinical Endocrinologists 1, 2
Available in fixed combinations once daily: insulin glargine + lixisenatide (iGlarLixi) and insulin degludec + liraglutide (IDegLira) 1, 2

The second option is basal insulin plus prandial insulin, starting with a single injection of rapid-acting insulin before the largest meal and advancing to a basal-bolus regimen with multiple injections if necessary, as suggested by the Endocrine Society 2, 1
Rapid-acting insulin analogs (lispro, aspart, or glulisina) are preferred 2, 1

The third option is switching to premixed insulin, with two daily doses of premixed insulin (such as 70/30 NPH/regular, 70/30 aspart mix, or 75/25 or 50/50 lispro mix) administered generally before breakfast and before dinner, as an alternative option 2, 1

Metformin should be maintained (unless contraindicated) 1, 2
Consider suspending sulfonylureas and DPP-4 inhibitors 2
Consider adding thiazolidinediones or SGLT2 inhibitors in patients with suboptimal glycemic control requiring high doses of insulin, as recommended by the American Association of Clinical Endocrinologists 2, 1

Dose titration is crucial once the insulin regimen is initiated, with adjustments based on blood glucose levels and the pharmacodynamic profile of each formulation 1

Inhaled insulin is contraindicated in patients with chronic pulmonary disease and not recommended for smokers, according to the American Thoracic Society 2, 1
SGLT2 inhibitors should be used with caution due to the risk of diabetic ketoacidosis, as warned by the Food and Drug Administration 3
The combination of basal insulin with GLP-1 RA may be less tolerated and more costly than regimens using only insulin, as noted by the American College of Clinical Endocrinologists 2

The final choice of therapy should consider efficacy, cost, potential side effects, comorbidities, and patient preferences, but current evidence clearly favors the combination of basal insulin with a GLP-1 receptor agonist as the most effective option for most patients with an insufficient insulin regimen, as stated by the American Diabetes Association 1