Do patients on dialysis (hemodialysis) require more or less insulin?

Insulin Requirements in Patients on Dialysis

Patients on hemodialysis require significantly less insulin compared to their pre-dialysis requirements, with recommended reductions of 35-50% in total daily insulin doses due to decreased insulin clearance and impaired gluconeogenesis. 1

Pathophysiology of Insulin Requirements in Dialysis

• Patients with early CKD stages experience increased insulin resistance, requiring higher insulin doses, but as they progress to end-stage kidney disease (ESKD) and dialysis, they need substantially less insulin 1
• The kidney normally clears 30-80% of insulin, so decreased kidney function in dialysis patients leads to reduced insulin clearance and prolonged insulin action 1
• Several mechanisms contribute to hypoglycemia risk in dialysis patients:
  • Decreased gluconeogenesis by the kidneys 1
  • Impaired insulin clearance and reduced insulin degradation 1
  • Increased erythrocyte glucose uptake during hemodialysis 1
  • Impaired counterregulatory hormone responses 1
  • Nutritional deprivation common in dialysis patients 1

Specific Insulin Dose Adjustments for Dialysis Patients

• For patients with type 1 diabetes on dialysis: reduce total daily insulin dose by 35-40% 1
• For patients with type 2 diabetes on dialysis: reduce total daily insulin dose by approximately 50% 1
• Specifically for pre-hemodialysis days: reduce basal insulin dose by 25% 1, 2
• Some patients (15-30%) with ESKD may experience "burn-out diabetes," requiring minimal or no insulin therapy 1, 2

Clinical Considerations and Monitoring

• Hemodialysis itself can remove insulin, with studies showing significant decreases in plasma insulin levels during passage through the dialyzer 3
• Glucose levels typically decrease significantly (up to 35.8%) during hemodialysis sessions 4
• Continuous glucose monitoring is recommended for dialysis patients to detect asymptomatic and nocturnal hypoglycemia 1
• HbA1c is less reliable in dialysis patients due to decreased red blood cell lifespan and anemia 2

Practical Approach to Insulin Management

• For insulin-naive dialysis patients or those on low doses, start with 0.3-0.5 units/kg/day 1
• For patients already on higher insulin doses (≥0.6 units/kg/day), reduce the total daily dose by 20% when hospitalized 1
• Consider switching from NPH insulin to insulin glargine, which has been shown to improve glycemic control and reduce hypoglycemic episodes in hemodialysis patients 5
• For peritoneal dialysis patients, insulin requirements may actually increase due to glucose absorption from dialysate, with each additional 2.5% 2L exchange potentially requiring 7.5 additional units of insulin per day 6

Hypoglycemia Prevention

• Monitor blood glucose more frequently on dialysis days and the day after 2
• Consider using a basal-plus approach rather than basal-bolus insulin regimens to minimize hypoglycemia risk 1
• Target more moderate fasting blood glucose levels (110-130 mg/dL) rather than aggressive targets 2
• Be vigilant for signs and symptoms of hypoglycemia, which may be more common and more dangerous in dialysis patients 2

Remember that insulin requirements in dialysis patients follow a biphasic course - increasing in early CKD but significantly decreasing in advanced CKD and dialysis - making careful dose adjustments essential to prevent dangerous hypoglycemic episodes.