What is the optimal diabetes management for a patient with end‑stage renal disease receiving peritoneal dialysis?

Optimal Diabetes Management for ESRD Patients on Peritoneal Dialysis

Target an HbA1c of 7-8% using reduced insulin doses (approximately 50% reduction for type 2 diabetes, 35-40% for type 1 diabetes), continuous glucose monitoring, and lower glucose-concentration dialysate solutions when feasible. 1, 2

Glycemic Targets

• Aim for HbA1c between 7-8% rather than the standard <7% target, as this range shows the most favorable association with mortality in advanced CKD and minimizes hypoglycemia risk while maintaining adequate glycemic control. 1
• Target fasting blood glucose of 110-130 mg/dL rather than aggressive targets, as very low HbA1c levels create a U-shaped mortality curve in dialysis patients. 2, 3
• Recognize that HbA1c underestimates actual glycemic control in peritoneal dialysis patients due to anemia, erythropoietin use, and decreased red blood cell lifespan. 1, 3

Insulin Dose Adjustments

For Type 2 Diabetes:

• Reduce total daily insulin dose by approximately 50% when initiating dialysis, as decreased kidney clearance leads to prolonged insulin action. 2, 3
• Monitor for "burn-out diabetes" phenomenon, which affects 15-30% of ESKD patients who may require minimal or no insulin therapy. 2, 3

For Type 1 Diabetes:

• Reduce total daily insulin dose by 35-40% when starting dialysis. 2
• Consider further 25% reduction in basal insulin on pre-dialysis days to prevent hypoglycemia. 2

Mechanism: The kidney normally clears 30-80% of insulin, so ESKD dramatically reduces insulin clearance while simultaneously impairing gluconeogenesis, creating a perfect storm for hypoglycemia. 2

Glucose Monitoring Strategy

Implement continuous glucose monitoring (CGM) as the primary monitoring method rather than relying on intermittent fingersticks, which miss most hypoglycemic episodes during and after dialysis. 2, 4

Critical Glucose Meter Considerations for Peritoneal Dialysis:

• Never use glucose meters with glucose dehydrogenase-pyrroloquinoline quinone (GDH-PQQ) or glucose oxidase (GO) methodology in patients receiving icodextrin-based peritoneal dialysis solutions, as these produce falsely elevated readings that can mask dangerous hypoglycemia. 1, 2, 4, 5
• Use only meters with hexokinase (HK), GDH-NAD, or GDH-FAD methodology to avoid interference from icodextrin metabolites. 2
• This interference has caused symptomatic hypoglycemia with falsely reassuring glucose readings, creating a dangerous clinical scenario. 5

Peritoneal Dialysate Selection

• Preferentially use lower glucose-concentration dialysate solutions (1.25% or 2.25%) instead of 3.86% solutions when clinically feasible to minimize systemic glucose absorption. 4
• Blood glucose increases within 1 hour of exchange with glucose-containing dialysate, with more prominent increments using 3.86% solutions. 4
• Consider icodextrin-based dialysate, which has no effect on or may reduce glucose levels compared to glucose-based solutions, but remember the glucose meter interference issue. 4

Medication Selection Beyond Insulin

Avoid:

• Metformin (risk of lactic acidosis in dialysis patients). 3
• Glyburide (prolonged hypoglycemia risk). 3
• SGLT2 inhibitors should not be initiated in dialysis patients, though may be continued if started before dialysis for cardiovascular benefits. 3

Consider:

• DPP-4 inhibitors for mild-moderate hyperglycemia as first-line oral agents. 3
• GLP-1 receptor agonists (such as dulaglutide) for patients with cardiovascular disease and eGFR >15 mL/min/1.73m². 3

Monitoring Frequency and Timing

• Monitor blood glucose more frequently on dialysis days and the day after, as peritoneal dialysis patients experience glycemic excursions related to hypertonic exchanges. 3, 4
• CGM metrics (mean glucose, glucose management indicator, time-in-range) provide more reliable assessment than HbA1c in this population. 2, 4
• Watch for asymptomatic and nocturnal hypoglycemia, which are common but often missed with traditional monitoring. 2

Key Clinical Pitfalls to Avoid

1. Never rely solely on HbA1c for glycemic management, as it correlates poorly with actual glycemic control in dialysis patients and typically underestimates mean glucose levels. 1, 2

2. Avoid aggressive glycemic targets that increase hypoglycemia risk without mortality benefit—the risk-benefit ratio shifts unfavorably in ESKD. 1, 2

3. Remember the glucose meter interference with icodextrin—this has caused real-world harm when patients received insulin based on falsely elevated readings while actually hypoglycemic. 1, 2, 5

4. Don't forget insulin dose reduction—patients progressing from early CKD (where they need more insulin due to resistance) to ESKD require substantially less insulin due to reduced clearance. 2

Practical Algorithm

1. Reduce insulin doses immediately upon dialysis initiation (50% for type 2 DM, 35-40% for type 1 DM). 2
2. Implement CGM to capture glycemic variability and detect asymptomatic hypoglycemia. 2, 4
3. Verify glucose meter methodology and switch if using GDH-PQQ or GO methods with icodextrin dialysate. 1, 2
4. Optimize dialysate prescription by using lower glucose concentrations when ultrafiltration goals permit. 4
5. Target HbA1c 7-8% with fasting glucose 110-130 mg/dL. 1, 2
6. Monitor for burn-out diabetes and adjust medications accordingly. 2, 3