Recent advances in the pathophysiology and management of protein-energy wasting in chronic kidney disease

Abstract

Protein-energy wasting (PEW) is a syndrome that consists of metabolic and nutritional abnormalities that often occur in chronic kidney disease (CKD), and PEW has been found to be associated with increased morbidity and mortality. A review was conducted to identify publications detailing the pathophysiology and management of PEW in CKD. The International Society of Renal Nutrition and Metabolism (ISRNM) has recently published the consensus statement of current knowledge regarding the etiology of PEW in CKD. Although insufficient food intake due to poor appetite and dietary restrictions contributes to the development of PEW, many other factors must be present for PEW to develop. The others include uremia-induced alterations such as increased energy expenditure, chronic inflammation, metabolic acidosis, and endocrine disorders that lead to a state of hypermetabolism and result in excess muscle and fat catabolism. In addition, comorbid conditions associated with CKD, low physical activity, frailty, and dialysis itself also contribute to the development of PEW. Serial assessments of the nutritional status of CKD patients by means of several scoring tools, including the Subjective Global Assessment (SGA), Malnutrition Inflammation Score (MIS), Geriatric Nutritional Risk Index (GNRI), and PEW diagnostic criteria, are recommended to diagnose and manage PEW. This review summarized recent advances in the etiology and evaluation of PEW of CKD patients. However, there are few treatment options for PEW with proven efficacy in terms of improved quality of life, morbidity, and mortality. Proposed therapeutic interventions need to be evaluated in randomized controlled trials to determine whether they improve clinically relevant outcomes.