What are the recommendations for insulin therapy in light of new findings on its negative effects?

Recommendations for Insulin Therapy in Light of Negative Effects

Despite potential negative effects, insulin therapy remains essential for patients with diabetes when indicated, but should be optimized using modern formulations, delivery methods, and combination therapies to minimize risks while maintaining glycemic control.

Understanding Insulin's Negative Effects

Recent research has identified several concerning adverse effects associated with insulin therapy:

• Hypoglycemia: The most common and dangerous adverse effect 1
• Weight gain: Common with insulin therapy
• Injection site issues: Lipohypertrophy and lipoatrophy
• Cardiovascular risk: Increased risk in type 2 diabetes, particularly with higher doses 2
• Psychological burden: Including needle phobia and treatment adherence challenges 3

Current Guideline-Based Recommendations

For Type 1 Diabetes:

1. Multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII) are recommended for most people with type 1 diabetes 4
2. Insulin analogs should be used to reduce hypoglycemia risk 4
3. Patient education on matching prandial insulin to carbohydrate intake, premeal glucose levels, and anticipated activity is essential 4
4. For patients with frequent nocturnal hypoglycemia, consider sensor-augmented low glucose threshold suspend pumps 4

For Type 2 Diabetes:

1. Delay insulin when possible: GLP-1 receptor agonists are preferred to insulin when possible 4
2. Consider early insulin only if there is:
   • Evidence of ongoing catabolism (weight loss)
   • Significant hyperglycemia symptoms
   • Very high A1C levels (>10%) or blood glucose levels (≥300 mg/dL) 4
3. Combination therapy: If insulin is used, combination with GLP-1 receptor agonists is recommended for greater efficacy, durability, and reduced weight gain and hypoglycemia 4
4. Continue metformin when initiating insulin therapy unless contraindicated 4

For Hospital Settings:

• Target glucose range: 140-180 mg/dL for most hospitalized patients 4
• More stringent goals (110-140 mg/dL) may be appropriate for selected patients (e.g., cardiac surgery) if achievable without significant hypoglycemia 4
• Basal insulin or basal plus bolus correction is preferred for non-critically ill hospitalized patients with poor oral intake 4
• Avoid sliding scale insulin regimens alone in the hospital setting 4

Strategies to Mitigate Insulin's Negative Effects

1. Optimize Insulin Regimens

• Use insulin analogs rather than human insulins to reduce hypoglycemia risk 4
• Consider sensor-augmented insulin pump therapy for patients with recurrent hypoglycemia 5
• Monitor for overbasalization: Clinical signals include basal dose >0.5 units/kg/day, high bedtime-morning glucose differential, hypoglycemia, and high glycemic variability 4

2. Combine with Other Agents

• Add metformin to insulin therapy to reduce insulin requirements and improve metabolic control in overweight/obese patients 4
• Consider GLP-1 receptor agonists with insulin for greater efficacy and reduced weight gain and hypoglycemia risk 4
• SGLT2 inhibitors may be used to improve glucose control and reduce total daily insulin dose, but monitor for ketoacidosis 4

3. Address Adherence Barriers

• Common reasons for insulin omission include: being too busy, traveling, skipped meals, stress/emotional problems, and public embarrassment 3
• Simplify regimens when possible to improve adherence
• Consider technology solutions like smart pens or pumps to improve adherence 6

Monitoring for Adverse Effects

1. Regular hypoglycemia assessment:

   • Hypoglycemia is the most common adverse effect of insulin therapy 1
   • Monitor closely in patients with hypoglycemia unawareness
   • Assess for risk factors: male gender, high glucose variability, and reduced kidney function 5

2. Cardiovascular risk monitoring:

   • Systematically assess cardiovascular risk factors at least annually 4
   • Consider insulin dose reduction when possible in patients with high cardiovascular risk 2

3. Weight monitoring:

   • Regular weight assessment
   • Consider combination therapy to mitigate insulin-induced weight gain

Key Pitfalls to Avoid

1. Overreliance on sliding scale insulin regimens - strongly discouraged in hospital settings 4
2. Delayed insulin dose adjustment - timely titration is important for glycemic control 4
3. Ignoring hypoglycemia risk - especially in patients with reduced kidney function or the elderly 5
4. Failing to monitor potassium levels when administering insulin intravenously - insulin can cause hypokalemia 1
5. Not addressing adherence issues - one-third of patients report insulin omission at least 1 day per month 3

By implementing these recommendations, clinicians can optimize insulin therapy while minimizing its potential negative effects, ultimately improving patient outcomes in terms of morbidity, mortality, and quality of life.