What is the recommended insulin dosing strategy for a patient with Chronic Kidney Disease (CKD) on dialysis?

Insulin Dosing for Patients with CKD on Dialysis

For patients with CKD on dialysis, insulin doses should be reduced by 35-50% of the total daily dose compared to patients with normal renal function, with a 25% reduction in basal insulin specifically on pre-hemodialysis days to prevent hypoglycemia. 1

Insulin Dosing Recommendations by Diabetes Type

Type 1 Diabetes

• Reduce total daily insulin dose by 35-40% for patients with CKD stage 5 on dialysis 1
• Reduce basal insulin dose by 25-30% for patients with CKD stage 3 1
• Reduce basal insulin dose by 25% specifically on pre-hemodialysis days 1

Type 2 Diabetes

• Reduce total daily insulin dose by 50% for patients with CKD stage 5 on dialysis 1
• Consider continuous glucose monitoring to detect asymptomatic and nocturnal hypoglycemia, which are common in advanced CKD 1

Practical Insulin Dosing Algorithm for Dialysis Patients

1. Calculate starting insulin dose:

   • For new insulin starts: Begin with lower doses (0.1-0.2 units/kg/day)
   • For existing insulin users: Reduce current total daily dose by 35-50% based on diabetes type

2. Distribute insulin appropriately:

   • Use 70% of total dose as basal insulin in the morning (not at bedtime) 1
   • Avoid rapid-acting and short-acting insulin at bedtime 1

3. Adjust for dialysis schedule:

   • Reduce basal insulin by 25% on pre-hemodialysis days 1
   • For peritoneal dialysis: Consider higher insulin requirements if using dextrose-containing dialysate

4. Monitor and titrate:

   • Target fasting glucose: 90-150 mg/dL (5.0-8.3 mmol/L) 1
   • If >50% of fasting glucose values are above target: Increase basal dose by 2 units
   • If >2 fasting glucose values/week are <80 mg/dL (<4.4 mmol/L): Decrease dose by 2 units 1

Special Considerations for Dialysis Patients

Hemodialysis Patients

• Risk of hypoglycemia is highest on dialysis days due to improved insulin sensitivity and glucose clearance
• Monitor blood glucose more frequently on dialysis days
• Consider administering basal insulin in the morning rather than at bedtime to reduce nocturnal hypoglycemia risk 1

Peritoneal Dialysis Patients

• Dextrose-containing dialysate can cause hyperglycemia
• Insulin may be administered subcutaneously or intraperitoneally
• If adding insulin to dialysate, may need to increase dose by up to 30% due to loss to tubing and dilution 2

Monitoring Recommendations

• Blood glucose: Monitor every 6 hours initially, then adjust frequency based on stability
• Avoid relying solely on HbA1c for glycemic monitoring in dialysis patients as it may underestimate glycemic control 1
• Consider continuous glucose monitoring (CGM) to detect asymptomatic and nocturnal hypoglycemia 1
• Monitor for signs of hypoglycemia, which may be more common and severe in CKD patients

Common Pitfalls and How to Avoid Them

1. Overestimating insulin requirements:

   • Start with lower doses and titrate slowly
   • Remember that uremia reduces insulin clearance and increases insulin sensitivity

2. Relying solely on HbA1c:

   • HbA1c may underestimate glycemic control in dialysis patients due to reduced red blood cell lifespan
   • Use direct glucose measurements and consider CGM for more accurate assessment

3. Ignoring dialysis schedule:

   • Adjust insulin doses based on dialysis schedule
   • Be particularly vigilant about hypoglycemia risk on dialysis days

4. Failing to adjust for changes in nutritional status:

   • Malnutrition is common in dialysis patients and may reduce insulin requirements
   • Reassess insulin needs with significant changes in nutritional status

5. Using inappropriate oral agents:

   • Many oral antidiabetic agents are contraindicated or require dose adjustment in CKD
   • Insulin remains the safest option for glycemic control in advanced CKD and dialysis

By following these recommendations, clinicians can optimize glycemic control while minimizing the risk of hypoglycemia in patients with CKD on dialysis, ultimately improving patient outcomes and quality of life.