What adjustments should be made to the insulin regimen for a patient with Type 1 Diabetes Mellitus taking Novolog (Insulin Aspart) and Tresiba (Insulin Degludec) to achieve optimal glycemic control?

Insulin Regimen Optimization for Type 1 Diabetes

Direct Recommendation

Your patient's current insulin regimen requires immediate assessment and likely adjustment: first, verify her actual glucose control through self-monitoring data and A1C, then adjust the Novolog dose based on postprandial patterns and the Tresiba dose based on fasting glucose, using systematic titration protocols rather than maintaining static doses. 1

Current Regimen Assessment

Your 65-year-old woman with Type 1 diabetes is on:

• Basal insulin: Tresiba (insulin degludec) 200U/mL formulation, dose unclear from your question
• Prandial insulin: Novolog (insulin aspart) 20 units before each meal (60 units/day total)

This represents a basal-bolus regimen, which is the recommended approach for Type 1 diabetes 2. However, the fixed 20-unit prandial doses suggest the regimen may not be optimized.

Essential First Steps

Obtain critical data immediately:

• Most recent A1C value 1
• Self-monitoring blood glucose (SMBG) patterns: fasting, pre-meal, and 2-hour postprandial readings 1, 3
• Frequency and timing of any hypoglycemic episodes (particularly readings <70 mg/dL or <54 mg/dL) 1
• Current total daily Tresiba dose 3

Systematic Adjustment Protocol

If Fasting Glucose is Elevated (>130 mg/dL)

Adjust Tresiba (basal insulin):

• Increase by 2 units every 3 days until fasting plasma glucose reaches 70-130 mg/dL 1, 3
• Target fasting glucose of 80-130 mg/dL 1
• Monitor for hypoglycemia during titration 3

Critical threshold warning: If Tresiba dose exceeds 0.5 units/kg/day without achieving target, this signals "overbasalization" and requires adding adjunctive therapy rather than further dose increases 3

If Postprandial Glucose is Elevated (>180 mg/dL) Despite Adequate Fasting Control

Adjust Novolog (prandial insulin):

• The current fixed 20-unit dose before each meal is likely inappropriate 2, 1
• Teach carbohydrate counting: Most people with Type 1 diabetes should match prandial insulin dose to carbohydrate intake, premeal blood glucose, and anticipated activity 2
• Adjust each meal's Novolog dose independently by 1-2 units or 10-15% every 3-7 days based on 2-hour postprandial glucose readings after that specific meal 1
• Administer Novolog 15 minutes before each meal for optimal postprandial control 1

If Hypoglycemia is Occurring

Immediate dose reduction required:

• Reduce the insulin causing hypoglycemia by 10-20% 1, 3
• If nocturnal hypoglycemia: reduce Tresiba 4
• If postprandial hypoglycemia: reduce the Novolog dose for that specific meal 1
• Ensure patient carries 15-20 grams of fast-acting carbohydrate at all times 1
• Prescribe glucagon and educate family members on emergency use 1

Monitoring Requirements

Essential SMBG schedule during adjustment:

• Fasting glucose daily 1
• Pre-meal glucose before each meal 1
• 2-hour postprandial glucose after the largest meal (or after any meal being adjusted) 1
• Increase monitoring frequency during dose adjustments to detect hypoglycemia early 1

Target glucose ranges:

• Fasting/premeal: 70-130 mg/dL 1
• Postprandial: <180 mg/dL 1
• Check A1C every 3 months until target achieved 1

Common Pitfalls to Avoid

Do not continue fixed prandial doses: The same 20-unit dose for all meals ignores carbohydrate variability and is suboptimal for Type 1 diabetes 2. Each meal requires individualized dosing based on carbohydrate content, premeal glucose, and anticipated activity 2.

Do not delay insulin adjustment: If A1C remains above target despite apparent adequate dosing, reassess the entire regimen rather than accepting poor control 1.

Do not rotate injection sites between different anatomical areas: Rotate systematically within one anatomical area to prevent lipodystrophy and ensure consistent absorption 1.

Watch for overbasalization: If you find yourself continuously increasing Tresiba beyond 0.5 units/kg/day, stop and consider adding a GLP-1 receptor agonist rather than further basal increases 3.

Advantages of Current Insulin Choices

Tresiba (insulin degludec) offers specific benefits for this patient:

• Ultra-long duration of action >42 hours with flat, stable profile 5, 4
• Lower risk of nocturnal hypoglycemia compared to insulin glargine 4
• Flexibility in injection timing if needed (though consistent timing is preferred) 5
• The 200U/mL formulation is appropriate if she requires large basal insulin volumes 5

Novolog (insulin aspart) is appropriate as it is a rapid-acting analog that reduces hypoglycemia risk compared to regular human insulin 2.

When to Consider Regimen Changes

If A1C remains above target despite optimized basal-bolus therapy:

• Consider adding a GLP-1 receptor agonist, which can improve glycemic control while potentially reducing insulin requirements 1, 3
• Evaluate for insulin pump therapy (continuous subcutaneous insulin infusion) if the patient has mastered carbohydrate counting and desires tighter control 2

If frequent hypoglycemia persists despite dose reductions:

• Consider sensor-augmented insulin pump with low glucose threshold suspend feature 2