Associations of Protein−Energy Wasting Syndrome Criteria With Body Composition and Mortality in the General and Moderate Chronic Kidney Disease Populations in the United States

INTRODUCTION: It is unknown whether the criteria used to define Protein-energy wasting (PEW) syndrome in dialysis patients reflect protein or energy wasting in the general and moderate CKD populations. METHODS: In 11,834 participants in the 1999-2004 National Health and Nutrition Examination Survey, individual PEW syndrome criteria and the number of PEW syndrome categories were related to lean body and fat masses (measured by dual-energy absorptiometry) using linear regression in the entire cohort and CKD sub-population. RESULTS: protein and energy stores. When the number of PEW syndrome categories was defined by non-dietary categories alone, there was a monotonic inverse relationship with lean body and fat masses and strong positive relationship with mortality. In contrast, when dietary category alone was present, mean BMI was in the obesity range; additional presence of two non-dietary categories was associated with lower BMI and lower lean body and fat masses. Thus, the association of dietary category plus two additional non-dietary categories with lower protein or energy stores was driven by the presence of the two non-dietary categories. Results were similar in CKD subgroup. CONCLUSION: Hence, a definition of PEW syndrome without dietary variables has face validity and reflects protein or energy wasting.