What is the primary management approach for type 1 diabetes?

Primary Management of Type 1 Diabetes

The primary management approach for type 1 diabetes is intensive insulin therapy delivered through either multiple daily injections (MDI) of prandial and basal insulin or continuous subcutaneous insulin infusion (CSII) via insulin pump. 1, 2

Insulin Therapy Components

Multiple Daily Injections (MDI)

• Consists of:
  • Basal insulin: Long-acting insulin analog (glargine, detemir, degludec)
  • Prandial insulin: Rapid-acting insulin analog (aspart, lispro, glulisine) before meals
• Typically requires 3-4 injections per day 1
• Distribution: Approximately 50% basal and 50% prandial insulin 2

Continuous Subcutaneous Insulin Infusion (CSII)

• Delivers continuous basal insulin with patient-activated boluses for meals
• Shows modest advantages over MDI:
  • HbA1c reduction of approximately 0.30% 1
  • Reduced rates of severe hypoglycemia 1, 2
• Sensor-augmented pumps with low glucose suspend features can reduce nocturnal hypoglycemia 1, 2

Insulin Dosing Guidelines

• Initial dosing: 0.5 units/kg/day for metabolically stable patients (range: 0.4-1.0 units/kg/day) 1, 2
• Higher insulin requirements during:
  • Puberty
  • Pregnancy
  • Medical illness 1

Prandial Insulin Management

• Rapid-acting insulin analogs are preferred over regular human insulin to reduce hypoglycemia risk 1, 2
• Patients should be educated on matching prandial insulin to:
  • Carbohydrate intake
  • Pre-meal blood glucose levels
  • Anticipated physical activity 1, 2

Blood Glucose Monitoring

• Frequent blood glucose monitoring is essential for effective insulin therapy 2, 3
• Use fasting plasma glucose (FPG) values to titrate basal insulin 3
• Use both FPG and postprandial glucose (PPG) values to titrate mealtime insulin 3
• Continuous glucose monitoring (CGM) can improve glycemic control regardless of insulin delivery method 2, 4

Glycemic Targets

• Target HbA1c < 7% for most nonpregnant adults 2, 5
• For children with T1DM, including preschool children, target HbA1c < 7.5% 3
• Individualize targets based on hypoglycemia risk and comorbidities

Benefits of Intensive Insulin Therapy

• Reduced microvascular complications
• Reduced neuropathic complications
• Reduced cardiovascular events
• Modest reduction in all-cause mortality 2, 5

Insulin Administration Technique

• Use shortest needles available (4-mm pen, 6-mm syringe) to avoid intramuscular injection 3
• Rotate injection sites to prevent lipohypertrophy, which can distort insulin absorption 3
• Avoid injecting into areas of lipohypertrophy 3

Adjunctive Therapies

• Currently not FDA-approved for type 1 diabetes but being studied:
  • GLP-1 receptor agonists
  • DPP-4 inhibitors
  • SGLT2 inhibitors 1, 2
• Metformin may be considered in overweight/obese patients with poorly controlled type 1 diabetes to reduce insulin requirements 1

Hypoglycemia Management

• Treat hypoglycemia with 15-20g of glucose (preferably glucose tablets)
• Recheck blood glucose after 15 minutes and repeat treatment if hypoglycemia persists 1, 2
• Prescribe glucagon for all individuals taking insulin 2
• Educate family members and caregivers on glucagon administration 2

Common Pitfalls to Avoid

1. Abrupt discontinuation of oral medications when starting insulin therapy (risk of rebound hyperglycemia) 3
2. Intramuscular insulin injections, especially with long-acting insulins (risk of severe hypoglycemia) 3
3. Injecting into areas of lipohypertrophy (causes unpredictable insulin absorption) 3
4. Using sliding-scale insulin as the sole treatment strategy 2
5. Failing to adjust insulin doses for physical activity (risk of hypoglycemia) 2

The evidence strongly supports that intensive insulin therapy with either MDI or CSII, combined with proper education on insulin dosing and carbohydrate counting, is the cornerstone of type 1 diabetes management to reduce complications and improve quality of life.