Evidence based practice guidelines for the nutritional management of cancer cachexia.

INTRODUCTION

Scope and Purpose

The purpose of these guidelines is to provide dietitians in Australia with a user-friendly summary of the evidence to support the nutritional management of adult patients with cancer cachexia. This best available evidence is presented and used as a basis for providing recommendations about clinical practice.

The clinical questions were as follows:

* How should patients be identified for referral to the dietitian in order to maximise nutritional intervention opportunities?

* How should nutritional status be assessed?

* What are the goals of nutrition intervention for patients with cancer cachexia?

* What is the nutrition prescription to achieve these goals?

* Should eicosapentaenoic acid be included in the prescription?

* What are effective methods of implementation to ensure positive outcomes?

* Does nutrition intervention improve outcomes in patients with cancer cachexia?

This document is a general guide to appropriate practice to be followed only subject to the dietitian's judgement in each individual case. The guidelines are designed to provide information to assist decision-making and are based on the best information available at the date of compilation. The guidelines recommend intensive nutrition therapy. This has potential resource implications that may include additional staff, change to staff roles and increased use of high/protein energy supplements if they are considered. Therefore, in applying the guidelines these potential organisational and cost barriers need to be considered. 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.

Methods

A Steering Committee of dietitians with research expertise in nutritional management of cancer cachexia and evidence based guideline development produced the first draft of the clinical practice guidelines. Initial members of the guideline development team convened in December 2003 were Dr Judy Bauer (Chairperson--The Wesley Hospital, Brisbane), A/Prof Susan Ash (Queensland University of Technology, Brisbane) and Ms Wendy Davidson (Princess Alexandra Hospital, Brisbane). This group developed the initial draft and workshop presentation. Additional members of the team from August 2004 were Ms Jan Hill (Royal Brisbane & Women's Hospital, Brisbane), Ms Teresa Stock (Royal Brisbane & Women's Hospital, Brisbane), Dr Elisabeth Isenring (Flinders University, Adelaide) and Dr Marina Reeves (Queensland Cancer Fund, Brisbane).

The draft was modelled on other guidelines developed for the nutritional management of disease. A workshop of dietitians was convened at the 22nd National Conference of the Dietitians Association of Australia in May 2004 to consider the draft guidelines and provide peer review. Participants evaluated the guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument (The AGREE Collaboration). (1) Participant feedback from the workshop was incorporated into a second draft. The second draft of the guidelines was presented at a workshop for dietitians in Perth in November 2004, where again evaluation was completed using the AGREE tool. Participant feedback from the workshop was incorporated into the third draft. At both workshops case studies were presented to demonstrate the use of the guidelines. A statistician was consulted to clarify issues related to levels of evidence and incorporation of evidence from post-hoc analyses of randomised trials.

The relevant articles were identified by electronic database searches (up to and including April 2005). The reference lists of relevant articles were also hand searched for any additional studies. In areas where cachexia-specific data was lacking, results from studies of other groups of patients with cancer have been included, and identified as such.

The following search strategies were used for the electronic databases listed below. Details of the search results were retained by the guideline development team.

Search Terms

Term 1      Cancer or neoplasm or carcinoma or tumo?r
            Cancer* or neoplasm* or carcinoma or tumour
Term 2      Cachexia or cachectic or weight loss or malnourished or
              wasting
            Cachex* or cachect* or (weight los*) or malnourished or
              wast*
Term 3      Nutrition or diet
            Nutrition* or diet*
Search      = Terms 1 and 2 and 3
            Limited to adult humans
            Search updated with databases available April 2005
Electronic  The Cochrane Database of Systematic Reviews
databases   The Cochrane Central Register of Controlled Trials (CENTRAL)
            Medline Advanced 1950-2005/01
            PubMed (to include early 2005 publications)--Cancerlit
            CINAHL (1982-current)
            Web of Science
            EMBASE
            Health Source: Nursing/Academic Edition
            Cancernet
            Cancer Spectrum
            Australasian Medical Index (AMI)

The strength of the evidence was assessed using the level of evidence rating system recommended by the National Health and Medical Research Council (NHMRC) publication A Guide to the Development, Implementation and Evaluation of Clinical Practice Guidelines. (2) A table was developed to collate the evidence for screening, assessment, intervention and monitoring and evaluation against key outcome indicators. Levels of evidence, quality of study design, the strength of the effect and relevance to practice were considered in ranking the evidence.

The evidence rating system used in the guidelines is as follows:

Level I      Evidence obtained from a systematic review of all relevant
             randomised controlled trials
Level II     Evidence obtained from at least one properly designed
             randomised controlled trial
Level III-1  Evidence obtained from well-designed pseudo-randomised
             controlled trials (alternate allocation or some other
             method)
Level III-2  Evidence obtained from comparative studies with concurrent
             control and allocation not randomised (cohort studies),
             case-control studies, or interrupted time series with a
             control group
Level III-3  Evidence obtained from comparative studies with historical
             control, two or more single arm studies, or interrupted
             time series without a parallel group
Level IV     Evidence obtained from case studies, either post-test or
             pre- and post-test. (2)

For intervention studies, Level I is recommended as the gold standard. It was felt that clinical nutrition studies are difficult to complete in a blinded fashion and often the group most likely to benefit from the intervention is excluded for ethical reasons. For these reasons, recommendations based on lower levels of evidence but with strong quality of design, strength of effect and relevance has been included.

The guideline development team also used the NHMRC additional levels of evidence and grades for recommendations for developers of guidelines--Pilot Program. (3) This grading system for recommendations has been developed as an interim measure to assist guideline developers in assessing the entire body of evidence and indicating the strength of each guideline recommendation.

The grades of recommendation are:

Level A  Body of evidence can be trusted to guide practice
Level B  Body of evidence can be trusted to guide practice in most
         situations
Level C  Body of evidence provides some support for recommendation(s)
         but care should be taken in its application
Level D  Body of evidence is weak and recommendation must be applied
         with caution. (3)

The five components that are considered in judging the body of evidence are the volume of evidence, consistency of the results, potential clinical impact of the proposed recommendation, the generalisability of the body of evidence to the target population of the guideline and the applicability of the body of evidence to the Australian healthcare context. A recommendation cannot be graded as A or B unless the volume and consistency of the evidence components are both graded A or B.

Consultation Process

The third draft underwent additional peer, expert and consumer review. It was distributed to previous workshop participants, DAA oncology experts, DAA oncology interest groups, international dietitians who had expressed an interest in participation, oncologists, nurses, other professionals working in the area of cancer and consumers for additional comment. Participant feedback was incorporated into a final draft, which was endorsed by the DAA Practice Advisory Committee (September 2005) and the DAA Board (November 2005).

Review Process

The guidelines should be reviewed every three years to ensure they remain current. Responsibility for review lies with the guideline development team. Next Review Date: 2008.

Applicability

A number of workshops were held during the development stage to identify the applicability of the guidelines for dietitians in the practice area of cancer. These workshops included: the 22nd National Conference of the Dietitians Association of Australia in May 2004; and in Perth in November 2004. Once the guidelines had been endorsed a further workshop was held in Queensland in March 2006, sponsored by Queensland Health, for dietitians to apply the guidelines to particular case studies. Evaluation from all three workshops indicated that the guidelines were applicable for dietetic practice.

Editorial Independence

The guidelines were developed without the assistance of external funding. Where guideline development team members were authors of a published article, other members of the guideline development team evaluated the article for levels of evidence. Guideline development team conflict of interest declarations are: off label research support (Abbott: J, Bauer, S. Ash, W. Davidson) and support for conference attendance (Abbott: J, Bauer, S. Ash, W. Davidson; Novartis: J. Bauer, E. Isenring). The workshops conducted in 2004 at the DAA Conference in Melbourne and Perth were externally sponsored. The views or interests of the workshop sponsors have not influenced the final recommendations.