Evidence based practice guidelines for the nutritional management of chronic kidney disease.

INTRODUCTION

Scope and Purpose

The purpose of these guidelines is to provide dietitians in Australia and New Zealand with a summary of evidence based clinical guidelines related to the dietetic management of adult patients with chronic kidney disease. The patient target group is any adult patient fulfilling the definition and diagnostic criteria of Chronic Kidney Disease (CKD), excluding those with nephrotic syndrome. These guidelines by definition also exclude acute renal failure and transplantation.

The clinical questions were as follows:

* At what level of glomerular filtration rate (GFR) should patients be referred to the dietitian in order to maximise nutritional intervention opportunities?

* Which specific measures best reflect nutritional status or change in nutritional status in CKD?

* What are the goals of nutrition intervention for CKD?

* What is (are) the appropriate nutritional intervention(s) to optimise nutritional status in CKD and prevent malnutrition?

* What is the optimal method of implementation and follow up to ensure nutritional status is maintained or improved?

These guidelines are meant to serve as a general framework for handling patients with particular health problems. It may not always be appropriate to use these guidelines to manage clients because individual circumstances may vary. The independent skill and judgement of the health care provider must always dictate treatment decisions. These guidelines for practice are provided with the express understanding that they do not establish or specify particular standards of care, whether legal, medical or other. (1)

Methods

The Royal Brisbane and Women's Hospital (RBWH) Nutrition and Dietetics Department supported a project dietitian, Helen McLaughlin to undertake the search strategy of existing guidelines. An initial team led by Dr Susan Ash, from Princess Alexandra Hospital with Helen McLaughlin, Suzie Chesterfield and Helen McCoy from RBWH developed the framework and the initial draft, which was circulated to Queensland dietitians working in Nephrology Services. This draft was used for consultation and evaluation at a workshop of dietitians at the 21st National Dietitians Association Australia conference in May 2003. A national panel of experts was defined at the conference, the Australia and New Zealand Renal Guidelines Taskforce (ANZRGT), who have continued to refine the guidelines as discussed elsewhere (see 'Consultation Process').

Relevant guidelines and articles were identified by Medline database and Internet key word searches between April 2002 and October 2003. The evidence based practice guidelines for the dietetic management of chronic kidney disease were developed by summarising the nutrition components of the following published guidelines:

* Caring for Australians with Renal Impairment (CARI) Guidelines (2)

* Kidney Disease Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines (3-8)

* American Dietetic Association (ADA) Medical Nutrition Therapy Evidence-Based Guides for Practice: Chronic Kidney Disease (non-dialysis) Medical Nutrition Therapy Protocol (9)

* ADA Guidelines for Nutritional Care of Renal Patients (3rd ed) (10)

* European Dialysis and Transplant Nurses Association and European Renal Care Association (EDTNA/ERCA) Guidelines for the Nutritional Care of Adult Renal Patients. (11)

Where conflicting guidelines answering the same clinical question existed, the guideline with the strongest level of evidence was included. When conflicting supporting evidence was equal in quality and depth, CARI guidelines were selected preferentially as more relevant to the local environment. If similar information was proposed from more than one set of guidelines, all sources were acknowledged. Aspects of nutritional management not included in any of the guidelines were omitted. Due to the difficulties associated with research into nutritional management of kidney disease, an evidence-based approach could not be adopted for all aspects. For published guidelines based on opinion or agreed best practice without supporting research, recommendations have still been included to complete the document but are acknowledged as being open for wider variance in practice. In particular, adherence to process type guidelines may be strictly resource dependant.

The selected guidelines were reformatted into the following components: definition of disease, diagnostic criteria, clinical questions to be addressed, referral criteria, nutrition assessment, nutrition prescription and outcome measures, in line with established nutritional management process. Dietetic management of acute renal failure, transplantation, nephrotic syndrome or kidney disease in paediatrics is not included.

These guidelines include information taken from existing sets of guidelines based on scientific evidence, and where no evidence exists, published guidelines stating consensus opinion from experienced practitioners including dietitians have been included. These guidelines do not address many issues concerning the implementation of dietetic practice, such as using groups or individual consultations, educational strategies or counselling techniques. This is beyond the scope of these guidelines and neither the evidence nor consensus opinion currently exists to promote one form of practice over another.

The Appendix show the definitions and calculations required for the management of CKD.

Levels of evidence or opinion have been cited from the above documents and referenced in each guideline. Descriptions of the levels of evidence are listed in Table 1.

Consultation Process

These practice guidelines have undergone several stages of peer and expert review using the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument (The AGREE Collaboration). (12) The rigour of scientific process varies between guidelines. The K/DOQI and CARI guidelines have documented systematic search and review processes in place, which meet the NH & MRC and AGREE criteria for quality. The ADA and EDTNA/ERCA guidelines are less rigorous, but the information extracted from these documents is based on expert opinion and is unable to be assessed using an evidence based practice tool.

The first draft of these guidelines was presented at the Dietitians Association of Australia (DAA) 21st National Conference in Cairns in May 2003 and achieved support in principle. A national panel of experts was defined at the conference, the Australia and New Zealand Renal Guidelines Taskforce (ANZRGT) to oversee further development and formulation of the final document. Consultation with nephrologists and renal nurses was undertaken when the guidelines were presented at the 31st Annual Renal Society of Australasia Conference in Brisbane, also in May 2003. The second draft was reviewed by the ANZRGT in August 2003 with comments incorporated into the final document. ANZRGT launched the guidelines in Queensland on October 30, 2003 with the assistance of the Queensland Health Allied Health Core Practice Group. Following the launch of the 2003 Guidelines, a workshop was conducted at the DAA 22nd National Conference in Melbourne in May 2004, on implementing the guidelines, and the taskforce gathered feedback from the 6 month pilot period since launching the guidelines. Currently, the guidelines are published on the Queensland Health Electronic Publishing Service (QHEPS) Internet site and have been endorsed by DAA.

As part of the DAA endorsement process, consumer input was sourced from Kidney Health Australia's regional Advocacy Committees, which are comprised of CKD patients. A standardised feedback form was developed based on recommendations from the Queensland Health Charter of Patient Rights (http://www.health.qld.gov.au/qhppc/default.asp). Feedback from consultation in two states has indicated that overall consumers felt the guidelines provided a standardised approach to care, however, were concerned that in their current format were too technical to be understood by consumers. Consumers would have liked to have been involved from the outset and were particularly interested that minority groups such as Indigenous people and those from non-English-speaking backgrounds be considered in any educational material and that those in rural and remote areas receive the same access to dietetic care as people in metropolitan areas. Discussion at both the National DAA workshops in 2003 and 2004 recognised the importance of involving consumers particularly from Indigenous backgrounds in the development of education materials.

Review Process

These guidelines are based on other published guidelines and should be reviewed annually to ensure they remain current. Responsibility for review lies with Royal Brisbane and Women's Hospital in conjunction with the Australia and New Zealand Renal Guidelines Taskforce.

Next Review Date: October 2007.

Applicability

The applicability was tested by dietitians at two national workshops and one state workshop. The cost of implementing the guidelines was a human resource issue and participants in the workshops felt having the guidelines would assist in lobbying for more staff for patient management.

Editorial Independence

These guidelines have been developed as a quality activity without external funding, therefore there is no external influence on the content of the guidelines. No member of the guideline taskforce has any conflict of interest to declare relating to the development of these guidelines.

EVIDENCE BASED PRACTICE GUIDELINE FRAMEWORK

The framework for evidence-based practice for the nutritional management of CKD is presented in Figure 1.

[FIGURE 1 OMITTED]

EVIDENCE BASED STATEMENTS

The evidence based statements are listed under the headings described in the Nutrition Care Process in Figure 1, based on the stages of CKD (Table 2). A summary of the recommendations are in Table 3.

Criteria for Referral to Dietitian

Clinical question

At what level of Glomerular Filtration Rate (GFR) should patients be referred to the dietrtian in order to maximise nutritional intervention opportunities?

Evidence statement                                     Level of evidence

CKD Stages 3 and 4
CKD Stage 3 (GFR 30-59 mL/min)                         Level IV (2)
CKD Stage 4 (GFR 15-29 mL/min)                         Level III (4)
Protein energy malnutrition increases with             Level III-2 (4)
  deteriorating kidney function and is associated
  with adverse outcomes
Low protein and calorie intake is an important cause   Level III-3 (4)
  of poor nutritional status

CKD Stage 5
CKD Stage 5 (GFR <15 mL/min)                           Level I (2)
For patients undergoing haemodialysis and peritoneal   Level III (3)
  dialysis, nutritional status should be routinely
  assessed at commencement of dialysis and at regular
  intervals thereafter

Nutrition Assessment

Clinical question

Which specific measures best reflect nutrition status or change in nutritional status in CKD?

Evidence statement                                     Level of evidence

CKD Stage 3 and 4
Maintained percent (%) oedema-free (dry) actual body   Level II (2)
  weight reflects optimal nutritional status.
Body Mass Index (BMI) = 18.5-25, reflects optimal      Level IV (3)
  nutritional status.
Subjective global assessment (SGA) and percentage      Level IV (3)
  ideal body weight (BMI) reflect change in
  nutritional status.
Total body nitrogen, dual X-ray absorptiometry (DEXA)  Level IV (2)
  or bioelectrical impedance (BIA) reflect long-term
  nutritional adequacy.

CKD Stage 5
Maintained percent (%) oedema-free (dry) actual body   Level II (2)
  weight reflect optimal nutritional status.
Body Mass Index (BMI) = 23-26, reflects optimal        Level II (2)
  nutritional status.
SGA maintained or improved reflects nutritional        Level III-3 (2)
  status.
Nutritional status of patients on peritoneal dialysis  Level IV (2,3)
  should be monitored by methods appropriate to
  assess total body stores and detect early signs of
  malnutrition, such as normalised protein nitrogen
  appearance (nPNA) >0.9, total body nitrogen (TBN)
  and DEXA within the normal range.

Nutrition Prescription/Intervention

Clinical question

What are the goals of nutrition intervention for CKD?

Evidence statement                                     Level of evidence

Achieve and maintain desirable weight and adequate     Level III-2 (11)
  nutritional status.
Optimise status of comorbidities, blood glucose        Level III-2 (4)
  control in diabetes and fluid and sodium control in
  hypertension, phosphate control in
  hyperparathyroidism, lipid control and weight
  management.
Normalise or stabilise biochemical markers, such as a  Level III-2 (4)
  normalised protein appearance (nPNA)
  [greater than or equal to]0.8 g/day in
  haemodialysis.
Normalise or stabilise biochemical markers, such as a  Opinion (4)
  nPNA >0.9 g/day in peritoneal dialysis.
Maintain skeletal muscle stores and strength, using    Opinion (4)
  subjective global assessment (SGA), TBN and DEXA.

Clinical question

What are the prescriptions for appropriate nutritional intervention(s) to optimise nutritional status in CKD and prevent malnutrition?

Evidence Statement                                     Level of evidence

CKD Stage 3
Energy. Ideal kilojoule/calorie energy intake          Opinion (2)
  determined for age, gender and BMI and level of
  physical activity needs to be determined.
A nutritionally balanced diet with adequate energy
  intake to maintain a healthy weight needs to be
  prescribed.
Protein. A level of protein of 0.75-1.0 g/ideal body   Level I (2)
  weight (IBW)/day is recommended.

CKD Stage 4
Energy intake of at least 146 kJ/kg IBW/day (35 kcal/  Level II (2)
  kg IBW/day) with a moderate protein restriction to
  prevent protein energy malnutrition.
For patients >60 years, an energy intake of 125 kJ/kg  Level III-2 (3)
  IBW/day is recommended.
Protein intake for patients with GFR <25 mL/min,       Level II (2)
  should not be less than 0.75 g/kg IBW/day. At least
  50% should be of high biological value.
Phosphate intake restricted to 800-1000 mg/day and/or  Opinion (8)
  use of phosphate binders is serum phosphate >1.49    Level II (2)
  mmol/L and/or serum parathyroid hormone >7.7 pmol/L
  on more than 2 consecutive occasions.
Supplementation. Patients on a restricted protein      Level IV (2)
  diet (<0.75 g/kg IBW/day) should receive thiamine
  (>1 mg/day), riboflavin (1-2 mg/day) and vitamin B6
  (1.5-2 mg/day).

CKD Stages 3 and 4
Fat/Carbohydrate. Priority should be given to a diet   Opinion (2)
  aimed at preventing protein-energy malnutrition and
  reducing fat to <30% of daily energy intake with
  saturated fat limited to <10% energy. Carbohydrate
  should be utilised to make up the balance of
  required energy intake.
Sodium intake of <100 mmol/day is recommended if the   Opinion (2)
  patient is hypertensive and CKD is progressive.
Potassium intake should be reduced if serum K >6       Opinion (2)
  mmol/L
Phosphate intake restricted to 800-1000 mg/day and/or  Opinion (8)
  use of phosphate binders is serum phosphate >1.49    Level III-2/3 (3)
  mmol/L and/or serum parathyroid hormone >12.1
  pmol/L on more than 2 consecutive occasions.
Fluid intake needs to be adjusted to the degree of     Opinion (2)
  CKD and prevention of renal disease, oedema
  management and hypertension management.
Once fluid intake requires diuretics a liberal intake
  should be curbed.
Management of hypertension includes limiting fluid
  intake.
Vitamin D supplementation is required for patients     Level II (2)
  with GFR <50 mL/min and PTH level 3-6 times the
  normal range or histological evidence of
  osteodystrophy.

CKD Stage 5
Energy levels of 125-146 kJ (30-35 kcal)/kg IBW/day    Level IV (2)
  are recommended to prevent malnutrition.
Energy levels of at least 146 kJ (35 kcals)/kg         Level IV (3)
  IBW/day is recommended for those acutely ill <60
  years and 125-146 kJ (30-35 kcals)/kg IBW/day for
  those acutely ill >60 years.
Protein intake is recommended at 1.2-1.4 g/kg          Level IV (2)
  IBW/day, >50% high biological value protein.
In haemodialysis, protein intake at least 1.2 g/kg     Opinion (4)
  IBW/day when acutely ill.
In peritoneal dialysis, protein intake at least 1.3    Opinion (4)
  g/kg IBW when acutely ill.
In peritoneal dialysis, protein intake at least 1.5    Opinion (4)
  g/kg IBW/day with peritonitis.
Fat and Carbohydrate <7% energy from saturated fat,    Level III-2 (7)
  polyunsaturated fat, monounsaturated fat <20%
  energy, carbohydrate 50-60% energy.
Sodium. Individualised treatment is recommended based  Level IV (11)
  on oedema and hypertension. 80-110 mmol/day if
  restricted.
Potassium. Individualised treatment recommended based  Opinion (10)
  on biochemistry
Phosphate. Restrict intake to 800-1000 mg/day if       Opinion (4)
  serum phosphate >1.8 mmol/L, and/or PTH >33.3        Level III-2 (8)
  pmol/L
Fluid. For haemodialysis, restrict fluid to 500 mL +   Level III-2 (11)
  previous day's output.
For peritoneal dialysis, individualised treatment      Opinion (11)
  recommended based on oedema and hypertension. If
  fluid overloaded, 800 mL + previous day's output
  recommended.

Implementation and Management

Clinical question

What are effective methods of implementation to achieve positive outcomes in CKD?

Evidence statement                                     Level of evidence
EDUCATION

CKD Stage 3
Patients with decreased dietary intake or              Level IV (4)
  malnutrition need dietary modification, counselling
  and specialised nutrition therapy.
For patients with poorly controlled comorbidities,     Opinion
  refer to medical specialist.                         ANZRGT

CKD Stage 4
Pre end stage kidney disease education forms an        Level II (2)
  important part of management strategy to slow the
  progression of renal disease and may have a
  beneficial effect.
Nutrition counselling should encompass appropriate     Level III-2 (4)
  protein and energy intake.
Nutrition counselling should include fluid, sodium     Level IV (2)
  and potassium intake and weight management           Opinion (4)

CKD Stage 5
Every patient should receive intensive nutrition       Opinion (4)
  counselling based on an individualised care plan.
The care plan should focus on adequate protein and     Level IV (2)
  energy intake.

MONITORING AND EVALUATION
Recommended times for initial consultation are 45-60   Opinion (9)
  mins and review 20-30 mins, for all patients.

CKD Stage 5
Nutrition reviews for dialysis patients need to occur  Opinion (9)
  every 6 months.
Timing for outcomes to be monitored include:
* Monthly
  oedema free body weight and BMI                      Level II (2)
  serum albumin                                        Opinion (2)
* 3-6 monthly, dialysis adequacy (Kt/V)                Level IV (2)
  nPNA                                                 Level IV (2)
  Dietary interview                                    Opinion (2)
  SGA                                                  Level IV (2,4)
* 6-12 monthly, assessment of body stores using TBN/   Opinion (4)
  DEXA

REFERENCES

1 Splett PL. Developing and Validating Evidence Based Guides for Practice: A Tool Kit for Dietetics Professionals. Chicago, USA: American Dietetic Association, 2000.

2 Australian Kidney Foundation and Australia New Zealand Society of Nephrology. CARI Guidelines (Caring for Australians with Renal Impairment). Sydney: Australian Kidney Foundation and Australia New Zealand Society of Nephrology, 2003.

3 K/DOQI, National Kidney Foundation. Clinical practice guidelines for nutrition in chronic renal failure. Am J Kidney Dis 2000; 35 (Suppl. 2): s1-140.

4 National Kidney Foundation Kidney Disease Outcome Quality Initiative (K/DOQI) Advisory Board. K/DOQI clinical practice guidelines for chronic kidney disease: evaluation, classification and stratification. Am J Kidney Dis 2002; 39 (Suppl. 2): s1-246.

5 NKF-K/DOQI clinical practice guidelines for hemodialysis adequacy: update 2000. Am J Kidney Dis 2001; 37 (Suppl. 1): s7-64.

6 NKF-K/DOQI clinical practice guidelines for peritoneal dialysis adequacy: update 2000. Am J Kidney Dis 2001; 37 (Suppl. 1): s65-136.

7 K/DOQI clinical practice guidelines for managing dyslipidemias in chronic kidney disease. Am J Kidney Dis 2003; 41 (Suppl. 3): s1-79.

8 K/DOQI clinical practice guidelines for bone metabolism and disease in chronic kidney disease. Am J Kidney Dis 2005; 42: S7-169.

9 American Dietetic Association. Medical Nutrition Therapy Evidence-Based Guides for Practice: Chronic Kidney Disease (Non-dialysis) Medical Nutrition Therapy Protocol. Chicago: American Dietetic Association, 2002.

10 Wiggins KL. Guidelines for Nutritional Care of Renal Patients, 3rd edn. Renal Dietitians Dietetic Practice Group, American Dietetic Association. Chicago: American Dietetic Association, 2002.

11 EDTNA/ERCA. European Guidelines for the Nutritional Care of Adult Renal Patients. Eur Dial Transplant Nurses Assoc/Eur Ren Care Assoc J 2003; 29: s1-23. Available from URL: http://www.edtna-erca.org/patges/education/guidelines.php. Accessed 24 July 2006.

12 The AGREE Collaboration. Appraisal of Guidelines for Research and Evaluation (AGREE) Instrument. 2001. (Cited 31 Mar 2003.) Available from URL: http://www.agreecollaboration.org

13 National Health and Medical Research Council. A Guide to the Development, Implementation and Evaluation of Clinical Practice Guidelines. Canberra: Commonwealth of Australia, 1999. (Cited 9 December 2004.) Available from URL: http://www.nhmrc.gov.au/publications/synopes/cp65syn.htm09/12/2004

14 Splett P, Myers EF. A proposed model for effective nutrition care. J Am Diet Assoc 2001; 101: 357-63.

15 Hakel-Smith N, Lewis NM. A standardised nutrition care process and language are essential components of conceptual model to guide and document nutrition care and patient outcomes. J Am Diet Assoc 2004; 104: 1878-84.

16 Lowrie EG, Lew NL. Death risk in haemodialysis patients: the predictive value of commonly measured variables and an evaluation of death rate differences between facilities. Am J Kidney Dis 1990; 15: 458-82.

17 Australian Department of Health and Ageing. National Physical Activity Guidelines for Australians. Canberra: Australian Department of Health and Ageing, 1999.

18 The Australasian Creatinine Consensus Working Group. Chronic kidney disease and automatic reporting of estimated glomerular filtration rate: a position statement. Med J Aust 2005; 183: 138-41.

19 Mitch WE, Klahr S. Handbook of Nutrition and the Kidney, 4th edn. Philadelphia: Lippincott Williams and Wikins, 2002.

APPENDIX I: BACKGROUND TO EVIDENCE STATEMENTS

Diagnosis and Referral

Chronic Kidney Disease (CKD) is defined as the presence of kidney damage for 3 months or more, as defined by structural or functional abnormalities, with or without decreased glomerular filtration rate (GFR), OR, GFR less than 60 mL/min for more than 3 months with or without kidney damage. (2) Kidney damage is defined as pathologic abnormalities or markers of damage, including abnormalities in blood or urine tests or imaging studies. (4)

Calculations

Estimated Glomerular Filtration Rate (eGFR)

Modification of Diet in Renal Disease (MDRD) formula (18)

eGFR = 186 x ([SCR/88.4][.sup.-1.154]) x (age)[.sup.-0.203] x (0.742 if female) x (1.210 if African-American)

* Where eGFR = estimated glomerular filtration rate (mL/min/1.73 [m.sup.2]), SCR = serum creatinine concentration ([micro]mol/L), and age is expressed in years. An automated calculator for MDRD-based eGFR can be found at <http://www.kidney.org.au>.

* Please note that the African-American factor is not used in Australia and as the MDRD formula has not been validated in children, its use should be restricted to people over 18 years of age.

* eGFR values over 60 mL/min/1.73 [m.sup.2], should be reported as '>60 mL/min/1.73 [m.sup.2'], rather than as a precise figure.

* Specific clinical settings in which eGFR is not appropriate for use and GFR should be measured directly include:

* populations in which the MDRD equation is not validated (e.g. Asian people) or in which validation studies have not been performed (e.g. Aboriginal and Torres Strait Islander populations);

* severe malnutrition or obesity;

* extremes of body size and age;

* exceptional dietary intake (e.g. vegetarian diet or creatine supplements);

* disease of skeletal muscle, paraplegia, etc. and

* rapidly changing kidney function.

Normalised Protein Nitrogen Appearance (nPNA)[.sup.2]

Chronic renal failure

nPNA may be approximated by the Randerson formula

nPNA (g/kg/day) = [[urea excretion (mmol/day) x 0.209] + 15.71] / weight (kg)

Calculation of Ideal Body Weight (IBW) (19)

Aim for weight to be within BMI of 20-25 if GFR 15-59 and a BMI of 23-26 on a dialysis modality. A patient's ideal body weight can be adjusted (as per the equation below), particularly if a patient is obese BMI >30.

Adjusted Body Weight = [(Actual Weight - Ideal Weight) x 0.25] + Ideal Body Weight (IBW).

When to use actual or adjusted body weight

1 Use actual body weight (dry weight for dialysis patients) when:

* Weight is within reasonable range of ideal or standard body weight (recommended BMI range).

* Recent weight change has not occurred.

* The patient is not malnourished.

* The patient has been slightly overweight or underweight almost all of their lives.

2 Use adjusted body weight when patients are overweight/obese, using clinical judgement.

Table 1 Levels of evidence from original sources

Reference            Levels of evidence

NHMRC (13)           I                         II
                     Systematic review of all  At least 1 properly
                     relevant clinical trials  designed randomised
                                               clinical trial (RCT)
ADA/Splett,                                    1
2000 (1)                                       Evidence obtained from 1
                                               or more well-designed
                                               RCTs
ADA,                                           Grade I
2002 (9,10)                                    Studies of strong design
                                               for answering the
                                               questions addressed. The
                                               results are both
                                               clinically important and
                                               consistent with minor
                                               exceptions at most. The
                                               results are free of
                                               serious doubts about
                                               generalisability, bias,
                                               and flaws in research
                                               design. Studies with
                                               negative results have
                                               sufficiently large
                                               samples to adequate
                                               statistical power
CARI, 2003 (2)       Level A
                     Randomised controlled
                     trials and meta-analyses
K/DOQI,
2000 (3)
K/DOQI,                                        S
2002 (4)                                       Analysis of individual
                                               patient data from a
                                               single large,
                                               generalisable study of
                                               high methodological
                                               quality (for example
                                               NHANES III)
Guidelines for       No levels of evidence or opinion provided
Nutritional Care
of Renal Patients
(3rd ed) (10)
European Guidelines  'Examination of the scientific literature shows a
for the Nutritional  paucity of evidence on dietary advice in renal
Care of Adult Renal  failure. Therefore the guidelines are based on
Patients (11)        scientific evidence, where available, and on
                     consensus of what constitutes "best practice" where
                     not'

Reference            Levels of evidence

NHMRC (13)           III-1                     III-2
                     Well-designed pseudo-RCT  Comparative studies with
                                               concurrent controls and
                                               allocation not randomised
                                               (Cohort studies), case
                                               control studies, or
                                               interrupted time-series
                                               with a control group
ADA/Splett,          II-1                      II-2
2000 (1)             Evidence obtained from    Evidence obtained from
                     well designed control     well designed cohort or
                     trials without            case-controlled analytic
                     randomisation             studies, preferably from
                                               more than 1 centre or
                                               research group
ADA,                                           Grade II
2002 (9,10)                                    Studies of strong design
                                               but uncertainty attached
                                               to the conclusion because
                                               of inconsistencies among
                                               the results for different
                                               studies or because of
                                               doubts about
                                               generalisability, bias,
                                               research desigh flaws or
                                               adequacy of sample size.
                                               OR the evidence is solely
                                               of studies from weaker
                                               designs but results have
                                               been confirmed in
                                               separate studies and are
                                               consistent.
CARI, 2003 (2)
K/DOQI,                                        Evidence
2000 (3)                                       Mainly convincing
                                               scientific evidence
                                               limited added opinion
K/DOQI,                                        C
2002 (4)                                       Compilation of original
                                               articles into evidence
                                               tables
Guidelines for       No levels of evidence or opinion provided
Nutritional Care
of Renal Patients
(3rd ed) (10)
European Guidelines  'Examination of the scientific literature shows a
for the Nutritional  paucity of evidence on dietary advice in renal
Care of Adult Renal  failure. Therefore the guidelines are based on
Patients (11)        scientific evidence, where available, and on
                     consensus of what constitutes "best practice" where
                     not'

Reference            Levels of evidence

NHMRC (13)           III-3                      IV
                     Comparative studies with   Case series, either
                     historical control, 2 or   post-test or pretest and
                     more single-arm studies,   post-test
                     or interrupted time-
                     series without a parallel
                     control group
ADA/Splett,          II-3                       III
2000 (1)             Evidence obtained from     Descriptive
                     multiple time-series       observational studies
                     studies with or without    (no control or
                     intervention, or well      comparison group), case
                     designed studies with      series reports and
                     concurrent comparison      reports from expert
                     groups, studies with       committees, opinions of
                     dramatic results from      respected authorities
                     uncontrolled experiments   and documented clinical
                                                experience
ADA,                 Grade III                  Grade IV
2002 (9,10)          Limited studies of weak    The support of the
                     design. Evidence from      conclusion consists
                     studies of strong design   solely of the statement
                     is either unavailable      of informed medical
                     because no studies have    commentators based on
                     been done or because the   their clinical
                     studies that have been     experience,
                     done are inconclusive due  unsubstantiated by the
                     to lack of                 results of any research
                     generalisability, bias,    studies
                     design flaws or
                     inadequate sample size
CARI, 2003 (2)       Level B                    Level C
                     Descriptive studies        Consensus or opinion
K/DOQI,              Evidence and opinion       Opinion
2000 (3)             Descriptive studies        Consensus or opinion
K/DOQI,              R                          O
2002 (4)             Review of reviews and      Opinion
                     selected original
                     articles
Guidelines for       No levels of evidence or opinion provided
Nutritional Care
of Renal Patients
(3rd ed) (10)
European Guidelines  'Examination of the scientific literature shows a
for the Nutritional  paucity of evidence on dietary advice in renal
Care of Adult Renal  failure. Therefore the guidelines are based on
Patients (11)        scientific evidence, where available, and on
                     consensus of what constitutes "best practice" where
                     not'

Table 2 Stages of chronic kidney disease

Stage  Description                   GFR (mL/min/1.73 [m.sup.2])

1      Kidney damage with normal or  [greater than or equal to]90
         [up arrow] GFR
2      Kidney damage with mild       60-89
         [down arrow] GFR
3      Moderate [down arrow] GFR     30-59
4      Severe [down arrow] GFR       15-29
5      Kidney failure                <15 (or dialysis)

Table 3 Summary of recommendations for the nutritional management of
chronic kidney disease

CKD           Stage 3 (GFR 30-59) (4)    Stage 4 (GFR 15-29) (4)

Point of      GFR <60 mL/min (2,4)       GFR <30 mL/min (3)
referral
Time for      45-60 mins (9)             45-60 mins (9)
consultation
Biochemistry  Alb (4), K (9),            Alb (3), K (9), P[O.sub.4] (9),
and clinical  P[O.sub.4], (9) Cr, (9)    Cr, (9) bld glucose &
              bld glucose &              Hb[A.sub.lc] (for persons with
              Hb[A.sub.lc] (for persons  diabetes), (9) PTH, (8) BP, (9)
              with diabetes), (9)        lipids, (2) GFR, (9) Hb, (9)
              PTH, (8) BP, (9)           medications inc supplements (9)
              lipids, (2) GFR, (9)
              Hb, (9) medications inc
              supplements (9)
Nutrition     Dry wt, (2,4) BMI, (2)     Dry wt, (2,3) BMI, (2)
assessment    %IBW/SGA, (4) diet         %IBW/SGA, (3) diet assessment/
              assessment/nPNA, (2,4)     nPNA, (2,3) activity level and
              activity level and         limitations (9)
              limitations (9)
Nutrition
intervention
Energy        Ideal for age, gender,     At least 146 kJ/kg IBW (BMI
              BMI and activity           18.5-25), (2) 125-146 kJ/kg IBW
              level (2)                  >60 years (3)
Protein       0.75-1.0 g/kg IBW/day (2)  0.75-1.0 g/kg IBW (2) with
                                         adequate kJ intake (2) >50%
                                         HBV (2)
Sodium        <100 mmol if hypertensive  <100 mmol if hypertensive and
              and CKD is                 CKD is progressive (2)
              progressive (2)
Potassium     Not usually restricted,    If [K.sup.+] >6.0 limit
              If [K.sup.+] >6.0 limit    intake (2) to 1 mmol/kg IBW/day
              intake (6) to 1 mmol/kg
              IBW/day
Phosphate     If >1.49 mmol/L (or        If >1.49 mmol/L (or >target
              >target PTH) restrict to   PTH) restrict to 800-1000 mg/
              800-1000 mg/day (adj for   day (adj for protein) &/or
              protein) &/or binders (8)  binders (8)
Fluid         Individualised based on    Individualised based on CKD,
              CKD, oedema and            oedema and hypertension (2)
              hypertension (2)
Nutrition     Adequate protein and       Protein and energy
counselling   energy, (2,4) bld glucose  intake, (2,3) Na, K & fluid
              control in DM, (4) fluid   intake, (2) wt control (2,9),
              and Na control in HT, (4)  meal plan, (9) recipe
              lipid (2) & weight (4)     modification, self
              control, meal plan, (9)    monitoring, (9) physical
              self monitoring, (9)       activity (9)
              physical activity (17)
Review &      Dry wt & BMI monthly, (2)  Dry wt & BMI monthly, (2) 20-30
frequency of  20-30 min (9) r/v every    min (9) r/v every 1-3
follow up     6-12 months if no          months, (2) more frequently if
              evidence of malnutrition,  inadequate intake, concomitant
              more frequently if         illness, GFR <15 or
              malnourished (4)           malnourished; (3) SGA every
                                         6-12 months (2)

CKD           Stage 5 (4) Haemodialysis  Stage 5 (4) Peritoneal dialysis

Point of      Upon commencement          Upon commencement
referral
Time for      45-60 mins (10)            45-60 mins (10)
consultation
Biochemistry  Pre dial: Alb (2,3)        Alb (2,3) K (10),
and clinical  urea, (2,16) K (10),       P[O.sub.4] (10), lipids, (7)
              P[O.sub.4] (2),            PTH, (8) CaxP[O.sub.4] (2),
              CaxP[O.sub.4] (2),         urea &/or Cr, (2) Hb[A.sub.lc]
              lipids, (7) PTH, (8) Post  (if diab), (10) PD prescription
              dial: urea (10)            & fluid gains, (10) BP, (10)
              Hb[A.sub.lc] (if           medications, (10) Kt/V (3)
              diab), (10) HD freq &
              fluid gains, (10)
              BP, (10)
              medications, (10)
              Kt/V (3)
Nutrition     Dry wt, (2) BMI, (2)       Dry wt, (2) BMI, (2) %IBW, (3)
assessment    %IBW, (3) SGA, (2,3) diet  SGA, (2,3) diet
              assessment (2,3) or        assessment (2,3) or nPNA (2,3)
              nPNA (2,3)
Nutrition
intervention
Energy        125-146 kJ/kg IBW (BMI     146 kJ (35 kcal)/kg IBW (BMI
              22-25) (2) Acute illness;  22-25) (2) inc glucose from
              >146 kJ/kg IBW if <60      dialysate (9) Acute illness:
              years, (3) >125 kJ/kg IBW  >146 kJ/kg IBW/day (3)
              if >60 years (3)
Protein       1.2-1.4 g/kg IBW (2) >50%  Min 1.2 g/kg IBW; (2) >50%
              HBV (3) acute illness:     HBV (3) acute illness: >1.3
              >1.2 g/kg IBW (3)          g/kg IBW, (3) peritonitis; 1.5
                                         g/kg IBW (11)
Sodium        80-110 mmol/day (11)       Indiv treatment recommended, if
                                         restricted 80-110 mmol/day (11)
Potassium     1 mmol/kg IBW/day (10)     Indiv treatment recommended, if
                                         restricted l mmol/kg
                                         IBW/day (10)
Phosphate     If >1.78 mmol/L (or        If >1.78 mmol/L (or >target
              >target PTH) restrict to   PTH) restrict to 800-1000
              800-1000 mg/day (adj       mg/day (adj for protein) &/or
              protein) &/or binders (8)  binders (8)
Fluid         500 mL + PDUO (11)         Indiv treatment recommended, if
                                         fluid overloaded or
                                         hypertensive: 800 mL +
                                         PDUO (11)
Nutrition     Individual care plan, (3)  Individual care plan, (3)
counselling   adequate protein and       adequate protein intake, (2)
              energy intake, (2) fluid   appropriate energy intake, (2)
              & electrolyte              self monitoring, (10) meal
              management, (10) self      plan, (10) physical
              monitoring, (10) meal      activity (10)
              plan, (10) physical
              activity (10)
Review &      Dry wt, BMI & alb          Dry wt, BMI & alb monthly, (2)
frequency of  monthly, (2) 45-60         45-60 min (10) r/v every 6
follow up     min (10) r/v every 3-6     months inc nPNA, Kt/V, diet
              months inc nPNA, Kt/V,     assessment & SGA, (2) more
              diet assessment &          frequently if clinically
              SGA, (2) more frequently   indicated (2)
              if clinically
              indicated (2)

%IBW, percent ideal body weight; Alb, albumin; BMI, body mass index; BP,
blood pressure; CaxP[O.sub.4], calcium phosphate ratio; Cr, creatinine;
DEXA, dual xray absorptiometry; DM, diabetes mellitus; g, gram; Hb,
haemoglobin; Hb[A.sub.1c], glycosylated haemoglobin; HD, haemodialysis;
HT, hypertension; K, potassium; kg, kilogram; kJ, kilojoules; Kt/V,
dialysis adequacy; L, litre; mg, milligram; mL, millitire; mmol,
millimole; Na, sodium; NPNA, normalised protein nitrogen appearance; PD,
peritoneal dialysis; PDUO, previous day's urine output; P[O.sub.4],
phosphate; PTH, parathyroid hormone; SGA, subjective global assessment;
TBN, total body nitrogen.