Nutritional evaluation of patients receiving dialysis for the management of protein-energy wasting: what is old and what is new?

Advances in the nutritional support of hospitalized patients in the early 1970s led to the recognition that tools were needed to evaluate the nutritional status of patients. The observation that malnutrition in patients receiving dialysis was associated with increased morbidity and mortality prompted many expert groups to develop nutritional scoring systems to be applied in these patients. Given the diverse and confusing terminologies that emerged from these publications, the International Society of Renal Nutritional and Metabolism convened an expert panel to recommend a new nomenclature and preferred methods to evaluate the nutritional status of patients with chronic kidney disease (CKD). The new and inclusive term protein-energy wasting (PEW) refers to a systematically defined condition based on certain criteria and reflects malnutrition and wasting caused not only by inadequate nutrient intake but also by depletion resulting from the inflammatory and noninflammatory conditions that prevail in this population. Serial assessment of nutritional status for detection and management of PEW is recommended using old and new scoring tools, including the Subjective Global Assessment (SGA), malnutrition inflammation score (MIS), Geriatric Nutritional Risk Index (GNRI), and PEW definition criteria. These tools, which are reliable methods and predictors of outcomes, are reviewed in this article.