Safety and efficacy of n-3 enriched nutritional supplements in the management of cancer cachexia
Thesis (MNutr (Interdisciplinary Health Sciences. Human Nutrition))--University of Stellenbosch, 2006.
Background At least 40 - 80% of all cancer patients develop some degree of clinical malnutrition and cachexia. The complex and multi-factorial nature of cancer cachexia and the inability of conventional nutrition intervention to reverse or attenuate the effects of this syndrome have driven investigators to consider new therapies and approaches to manage the syndrome of cancer cachexia including eicosapentaenoic acid (EPA), an n-3 fatty acid of fish oil origin. Objectives The aim of this study was to review Phase I, Phase II and Phase III (RCT) trials investigating the safety and efficacy of n-3 supplementation in the treatment of cancer cachexia in adult patients with unresectable solid tumours, with special reference to weight loss, body composition, appetite, dietary intake, energy expenditure, functional status, acute phase response and quality of life. Adverse effects associated with EPA supplementation were also reviewed. Methodology and data collection The major databases were systematically searched for studies that met the inclusion criteria using a structured keyword search strategy or various combinations of these keywords. Relevancy of studies was assessed by two independent reviewers according to pre-determined inclusion and exclusion criteria. Quality was assessed by two independent reviewers using the Jadad scale. Data extraction was performed by the principal reviewer and one of the independent reviewers, and investigators of the included studies were contacted where further information was required. Meta-analysis was not appropriate due to heterogeneity of the data. However, where possible, the paired t-test was used for analysis of the data. Descriptive or non-quantitative analysis of the tabulated data provided a summary of the characteristics of the included studies enabling comparisons to be made between interventions and outcomes within the specified population. Results The search resulted in a total of 1408 citations, of which only 16 studies met the inclusion and exclusion criteria. Of these, only 4 studies were of a good quality. Although the reported data was incomplete and variable, the combined analyses suggested that the effect of EPA supplementation on weight, fat mass, dietary intake, energy expenditure, and acute phase response was not significant. Interestingly there appeared to be a significant increase increased or decreased? in lean body mass (p<0.05). There was little or no data to draw any conclusions regarding the effect of supplementation on appetite and quality of life. Conclusion Despite several limitations in this review, the data collected and analysed are suggestive of the beneficial effects of EPA supplementation, but there remains a significant lack of substantial evidence and conclusive statistical analysis to confirm that EPA supplementation is a safe and effective method of intervention in the management of patients with cancer cachexia.