What are examples of oral nutritional supplements for dialysis patients?

Oral Nutritional Supplements for Dialysis Patients

For dialysis patients requiring nutritional supplementation, renal-specific oral nutritional supplements (ONS) should be prescribed as the first-line intervention, with specific products including high-protein, energy-dense formulations designed for hemodialysis and peritoneal dialysis patients. 1, 2

Specific Product Categories and Characteristics

Renal-Specific Oral Supplements

• Renal-specific formulations are preferred over standard supplements because they are specifically designed to meet the unique macronutrient and micronutrient needs of dialysis patients while controlling phosphorus and potassium content. 1, 3
• Examples of renal-specific products studied include ONCE Dialyze and NEPRO, both providing approximately 370 kcal per serving with adapted electrolyte profiles. 3
• These formulations typically provide high protein content (1.0-1.2 g/kg/day contribution) and energy density (25-35 kcal/kg/day contribution) to meet dialysis-specific requirements. 1, 2

Key Nutritional Composition Requirements

• Protein content: Supplements should contribute toward the target of 1.2 g/kg body weight/day, with at least 50% from high biological value sources (whey protein, egg albumin). 1, 2
• Energy content: Should provide 30-35 kcal/kg/day for patients ≥60 years old, and 35 kcal/kg/day for younger patients. 1, 2
• Electrolyte modifications: Formulations must have controlled phosphorus (10-12 mg per gram of protein) and potassium content appropriate for dialysis patients. 1, 2

Optimal Timing and Administration Strategy

Timing Protocols

• Give ONS 2-3 hours after regular meals to avoid suppressing normal food intake and prevent nutritional substitution. 1, 2
• Late evening administration reduces overnight catabolism without interfering with daytime food consumption. 1, 2
• Intradialytic delivery during hemodialysis sessions (three times weekly) has demonstrated superior compliance rates compared to home-based supplementation. 1, 2, 4

Dosing Strategy

• Minimum 3-month trial is recommended to assess effectiveness on nutritional parameters before considering escalation to tube feeding or parenteral nutrition. 1
• Standard dosing provides one unit (237 mL) containing approximately 16.6 g protein, 22.7 g fat, and 53 g carbohydrates per dialysis session or daily. 1

Clinical Evidence for Effectiveness

Proven Benefits

• Serum albumin improvement: ONS increases mean serum albumin by 0.19 g/dL (95% CI 0.05 to 0.33), with greater effect in hemodialysis patients (0.28 g/dL) and malnourished patients (0.31 g/dL). 5
• Malnutrition Inflammation Score (MIS): Renal-specific ONS reduces MIS by 29% over 30 days compared to dietary counseling alone. 3
• Serum prealbumin: Increases by 2.81 mg/dL (95% CI 2.19 to 3.43) with ONS use. 5
• Mid-arm muscle circumference: Improves by 1.33 cm (95% CI 0.24 to 2.43), indicating preservation of lean body mass. 5

Population-Specific Responses

• Hemodialysis patients show greater response than peritoneal dialysis patients, with more pronounced albumin improvements. 5
• Malnourished patients (baseline albumin <3.5 g/dL) demonstrate the most significant benefit from supplementation. 5, 4

Escalation Pathway When ONS Fails

Step 1: Optimize Oral Route First

• Ensure dietary counseling has been provided by a registered dietitian nutritionist before initiating ONS. 1, 2
• Address reversible causes of poor intake: uremic toxicity, medication side effects, depression, inadequate dialysis. 2
• Trial intradialytic ONS delivery if home compliance is poor. 1, 2

Step 2: Enteral Tube Feeding

• Nasogastric tube feeding should be considered when ONS fails to achieve 70% of nutritional requirements. 1
• Nasojejunal feeding is preferred for patients with gastroparesis unresponsive to prokinetic agents. 1, 2
• PEG or PEJ placement should be considered for long-term tube feeding needs (>4-6 weeks anticipated). 1
• Use hemodialysis-specific tube feeding formulas rather than standard formulas to maintain appropriate electrolyte control. 1

Step 3: Intradialytic Parenteral Nutrition (IDPN)

• IDPN is indicated for malnourished hemodialysis patients who fail to respond to or cannot tolerate ONS or enteral nutrition. 1
• Administered during hemodialysis sessions (3-4 hours, three times weekly) via the extracorporeal circuit. 1
• Not superior to ONS but provides a safe alternative when enteral routes are not feasible. 1

Step 4: Total Parenteral Nutrition (TPN)

• Reserved for patients with protein-energy wasting when nutritional requirements cannot be met with oral and enteral intake. 1
• Requires central venous access and carries higher infection risk. 6

Critical Monitoring Parameters

Biochemical Monitoring

• Serum albumin: Monitor every 1-4 months with target ≥3.5 g/dL. 2
• Normalized protein nitrogen appearance (nPNA): Target ≥0.9 g/kg/day. 2
• Phosphorus and potassium: Monitor closely when increasing protein intake, as protein-rich supplements are major sources of these minerals. 1, 2
• Screen for refeeding syndrome: Monitor phosphorus, potassium, and magnesium when initiating nutritional support in severely malnourished patients. 2

Anthropometric Monitoring

• Body weight: Assess for >10% loss over 6 months. 2
• BMI: Maintain >20 kg/m². 2
• Mid-arm muscle circumference: Assess muscle mass preservation. 5

Dialysis Adequacy

• Kt/V and URR: Must be monitored and dialysis prescription adjusted when increasing protein intake to prevent uremia intensification. 2

Common Pitfalls to Avoid

Prescription Errors

• Do not use formulas designed for non-dialysis CKD patients (low protein content) in dialysis patients, as protein requirements are higher. 1
• Do not restrict protein below 1.2 g/kg/day in an attempt to reduce uremia—instead optimize dialysis adequacy. 2
• Avoid standard (non-renal) supplements as first-line therapy due to inappropriate electrolyte content. 1

Administration Mistakes

• Do not give ONS immediately before or with meals, as this suppresses regular food intake. 1, 2
• Do not delay nutritional intervention waiting for severe malnutrition to develop—early intervention is more effective. 2

Monitoring Oversights

• Do not overlook gastrointestinal tolerance—approximately 20% of patients may experience intolerance requiring product adjustment. 1, 5
• Do not ignore compliance issues—intradialytic delivery significantly improves adherence compared to home-based supplementation. 1, 2

Special Considerations

Diabetic Dialysis Patients

• Protein intake of 1.0-1.2 g/kg/day should be maintained, with higher levels considered if needed for glycemic control. 1
• Monitor blood glucose closely when initiating carbohydrate-containing supplements. 1

Peritoneal Dialysis Patients

• Protein requirements are higher (1.2-1.3 g/kg/day) due to peritoneal protein losses of 5-15 g/24 hours. 1
• Standard ONS can be used, though renal-specific formulations are preferred. 1
• Amino acid dialysate is not recommended as a general strategy but may be considered if oral/enteral routes fail. 1