Nutritional Considerations in PD

Objectives Discuss risks and importance of poor nutrition How to assess nutritional state How to achieve good nutrition

Nutrition

Alternatives to Avoid

Nutrition in Patients with CRF Classes of nutrients - carbohydrates - fats - proteins - vitamins - minerals - water Essential nutrients - amino-acids - essential fatty acids - vitamins, elements Without these, an individual cannot function Dietary protein provide amino acids - body proteins Without sufficient dietary protein and energy, no growth or repair

Recommended Protein & Energy Intakes (g/kg BW/day) (kcal/kg BW/day) Healthy adults > 0.75# >35 CRF patients (non-dialyzed) ? 0.60 (high quality) >35 HD patients > 1.2 >35 CAPD patients > 1.2 >35 # safe for 97.5 % of the population (WHO 1985) CRF patients with GFR 30-20 ml/min reduce protein and energy intake (MDRD study) Protein and energy intake lower than recommended in a large proportion (20-60%?) of HD and CAPD patients

Protein-Energy Malnutrition A state of deficiency resulting from inadequate intake of protein and/or energy relative to physiological needs leading to progressive changes in body composition and function and nutrition

Nutrition is a balance between supply and demand

Accumulation of uremic toxins Negative Feedback Loop MALNUTRITiON Anorexa nausea vomiting Low protein and energy intake Low serum urea Accumulation of uremic toxins Loss of renal function J Bergström ASN -94

Major Metabolic Steps in Nutritional Deficiency Disease Well nourished individual Dietary survey Nutrient intake Biochem and physiol studies Individual at risk Signs & symptoms Malnourished individual Vital statistic

Patients at Risk of Developing Malnutrition Elderly Socially isolated Diabetes mellitus Recurrent peritonitis Active comorbid conditions Loss of RRF Inadequate solute removal

Risk Factors for Poor Nutrition Late start of dialysis Use of low protein diet Poor appetite Social factors Protein loss through peritoneum Increased with peritonitis Catabolic state

Effects of Renal Insufficiency Protein and Amino Acid Metabolism Altered metabolism of proteins & amino acids Intravascular alb pool may be reduced, even though serum albumin is normal Transferrin levels low Increased catabolism (higher levels of glucagon, PTH, toxins, acidosis) Changes in amino-acid profiles Increased risk of developing protein malnutrition Major cause of morbidity and mortality DPI also diminishes with declining GFR

Protein-Calorie Malnutrition in CRF Catabolic Factors Comorbid illness Physical inactivity Infections Metabolic acidosis Abnormal energy metabolism

Protein intake and GFR 10ml / min¯ GFR = ¯ 4.4g in DPI 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 DPI >50 25-50 24-10 <10 Ikizler, JASN 1995 GFR

Protein Intake in Pre-dialysis DPI N = 1687 0.0 0.2 0.4 0.6 0.8 1.0 1.2 70 45 25 9 GFR (mls / min) MDRD study ; JASN 1994

Catabolic Effects of Dialysis CAPD HD Loss of amino acids 2-4 g/day 14-28 g/week 9-13 g/dialysis 27-39 g/week Loss of glucose uptake ~25 g/dialysis (glucose free dialysate) Loss of protein 5-15 g/day (higher with peritonitis) Inflammatory stimuli Low grade inflammation (particles chemicals) Cytokine release Blood membrane contact

Causes of Anorexia Underdialysis particularly with loss of residual renal function Sensation of abdominal fullness Poor gastric emptying particularly in diabetics Hyperglycaemia and glucose absorption from excessive use of hypertonic dextrose Depression

Risk Factors for Obesity Use of hypertonic dialysate, particularly 3.86% dextrose, to maintain fluid balance High caloric intake, but low protein intake Lack of physical activity

Causes of Low Plasma Albumin (Malnutrition vs. Malnourished) True malnutrition Co-morbid conditions - Infection - Generalised vascular disease - Chronic inflammation - Proteinuria - Malignancy Old age Dietary preference

Assessment of Nutritional Status History and physical examination looking for loss of weight and muscle wasting Dietary history Plasma creatinine, urea, albumin, transferrin -  creatinine can mean  muscle mass and not  dialysis clearance -  creatinine can mean  muscle mass and not  dialysis clearance Anthropometry SGA (Subjective Global Assessment) Biochemical / laboratory tests

Anthropometry Mainly used as research tool Wolfson 1984

Subjective Global Assessment Four items assessed over 7 point scale Weight change What was weight change over last 6 months? Anorexia Has dietary intake changed? Subcutaneous tissue Fat and muscle wasting e.g., under eyes or shoulders Muscle mass and wasting - Examining temporalis muscle, prominence of clavicles, contour of shoulders etc

Subjective Global Assessment 1. Weight Change - in last 6 mths - % (<5, 5-10,>10) - in last 2 weeks 2. Dietary Intake - overall - pattern - duration - type 3. GIT Symptoms - > 6weeks 4. Functional Capacity - overall +change 1. Loss of subcutaneous fat 2. Loss of muscle mass 3. Oedema History PE

Subjective Global Assessment Severe malnutrition - ‘1 or 2’ ratings in most categories Mild to moderate - ‘3, 4 or 5’ ratings in most categories Mild to Well Nourished - ‘6 or 7’ ratings in most categories or continued improvement A - Well nourished B - Mild-Mod malnourished C - Severely malnourished

There is No Single Magic Nutritional Index Each has limitations Use of combinations gives corroborating information

Non-Nutritional Factors Affecting Albumin Fluid balance Infection/inflammation Urinary losses High dialysate losses

Non-Nutritional Factors Affecting Albumin Analytical method Gender Age Pregnancy Fluid balance Infection/inflammation Cardiac disease Malignancy Protein losses (urine, dialysate) Infection/inflammation related albumin is like an ‘negative’ acute phase protein Association between cardiac disease and hypoalbuminaemia (Foley 1996)

Albumin as a Negative Acute Phase Reactant Qureshi et al., 1995

Albumin as a Predictor However, Strong predictor of morbidity and mortality (CANUSA study) Albumin may be affected by protein intake However, Albumin is affected by non-nutritional factors Albumin may not increase in response to nutritional intervention

Serum albumin alone is neither necessary nor sufficient to indicate malnutrition

Serum Albumin and Death Risk Haemodialysis Patients <=2.5 2.5-3.0 3.0-3.5 3.5-4.0 4.0-4.5 >4.5 10 20 Serum Albumin (mg/dl) Relative Death Risk Lowrie et al, 1990

Target Protein Intake for PD Nitrogen balance is the reference method for determining adequacy of protein intake N Balance studies by Blumenkrantz and Bergstrom indicate that at 1.2 g protein/kg/day no patients were in negative nitrogen balance

Malnutrition in ESRD Target Intake for PD 4 5 3 2 1 0.9 1.0 1.1 1.2 1.3 1.4 1.5 Protein intake, g/kg body wt/day Nitrogen balance, g/day Blumenkrantz et al, KI 1982

How Can This Target Be Achieved?

Methods for Nutritional Support in PD Nutritional counseling Pharmacologic appetite stimulation Oral supplements Enteral formulas (nasogastric, PEG) Intravenous Intraperitoneal (nutritional dialysis)

Prevalence of Malnutrition is Similar in HD and PD* Mode #Studies #Pts % Malnourished HD 3 502 21-53 (28%) PD 3 401 26-56 (36%) * Evaluated by the same method

Nutrition: Guidelines 2002 All patients should undergo regular screening for undernutrition using as a minimum SGA, height weight and albumin Diagnosis of undernutrition should be considered if any of following are met: - BMI < 18.5 - unintentional loss of oedema free weight of > 10% in last 6 mths - plasma albumin below normal (value depends on assay) - Low SGA scores

Nutrition: Guidelines 2002 If undernutrition suspected - refer to dietitian to assess dietary intake measure CRP, plasma bicarbonate, dialysis adequacy and residual renal function Correct low dietary intake If intake adequate, look for infection if CRP high, and other catabolic factors such as acidosis, thyrotoxicosis and poorly controlled diabetes

What is Nutrineal™? Nutrineal™ is a peritoneal dialysis solution with amino acids instead of glucose which integrates dialysis and nutritional supplementation

Nutrineal™ Characteristics Amino acids as osmotic agent No glucose No change in dialysis procedures More physiologic pH Osmolality equivalent to 1.5% glucose Clearance equivalent to 1.5% glucose 40 mEq/L lactate

Amino Acid Content of Nutrineal™ (2.0 L) Essential Nonessential Histidine Alanine Isoleucine Arginine Leucine Glycine Lysine Proline Methionine Serine Phenylalanine Tyrosine Threonine Tryptophan Valine 14.1g (64%) 7.9 g (36%) Conditionally essential in renal patients

Bioavailability and Utilization Nutrineal™ How much is absorbed? How is it utilized (Anabolic?) - Nitrogen balance - IGF-1

Delivering 25% of daily protein intake In just one exchange Nutrineal can deliver 25% of the target Daily Protein Intake* With an absorption rate of 70-80% over 4-6 hours, one exchange of 2L Nutrineal provides approximately 18g of AAs to an average, stable, 60kg patient: that is 0.3 g/kg body weight/day, which represents 25% of the 1.2 g/kg body weight/day target intake1 * Recommended dosage for adults: one 2L or 2.5L bag/day 25% Target DPI Jones MR, et al., PDI, 1998;18(2):210-216

Bioavailability For 60 kg patient AAs Day 1 Protein and AA Losses Day 2 AA gains 0.3 g/kg 0.16g/kg Jones et al, PDI 1998;18:210-216

The Therapy Before Prescription: Check adequacy (Kt/V > 2; Cr.Cl. > 50 L./week) Correct possible acidosis (bicarbonate > 23 mmol/L.) Verify protein intake Review comorbid conditions Assess nutritional status Therapeutic Target: Protein intake of around 1.2 g/kg/day

Nutrineal® : an efficient and compliant way of delivering AA’s whilst providing dialysis

Managing Protein Needs with Nutrineal Target protein intake* = 1.2 g/kg/day One exchange with Nutrineal contributes the equivalent of 0.3 g/kg in an average patient (20-25% of daily target) *Kopple, 1997

Conclusion Poor nutrition common in PD patients and is adverse risk factor Important to assess nutritional status In malnourished patients - correct identifiable comorbidities - assess dialysis adequacy and increase dose if near or below target maximise oral intake Nutrineal