The Use of Visceral Proteins as Nutrition Markers: An ASPEN Position Paper

Abstract

Serum albumin and prealbumin, well‐known visceral proteins, have traditionally been considered useful biochemical laboratory values in a nutrition assessment. However, recent literature disputes this contention. The aim of this document is to clarify that these proteins characterize inflammation rather than describe nutrition status or protein‐energy malnutrition. Both critical illness and chronic illness are characterized by inflammation and, as such, hepatic reprioritization of protein synthesis occurs, resulting in lower serum concentrations of albumin and prealbumin. In addition, the redistribution of serum proteins occurs because of an increase in capillary permeability. There is an association between inflammation and malnutrition, however, not between malnutrition and visceral‐protein levels. These proteins correlate well with patients’ risk for adverse outcomes rather than with protein‐energy malnutrition. Therefore, serum albumin and prealbumin should not serve as proxy measures of total body protein or total muscle mass and should not be used as nutrition markers. This paper has been approved by the American Society for Parenteral and Enteral Nutrition Board of Directors.

Response to “Low albumin levels should be interpreted, but not ignored”

“…2 In addition, provision of nutrients (nitrogen) has not been shown to ameliorate inflammation, as recently identified by Merker et al In the analysis of acutely ill hospitalized patients by Merkel et al, C-reactive protein levels were not different based on nutrition intervention (intensive treatment vs standard treatment) over the 7-day study period. 3 What is known is that serum albumin is useful as a predictive marker of surgical risk, as highlighted in our position statement. 4 The use of serum albumin as a component of preoperative risk assessment is well documented because of its known relationship with operative morbidity and mortality.…”

Nutrition risk prevalence and nutrition care recommendations for hospitalized and critically-ill patients with COVID-19

“…Historically, albumin levels have been used as a biochemical marker of nutrition status. However, a recent publication, approved by ASPEN, argues that albumin is an indicator of inflammation, not malnutrition [47]. Albumin levels decline during the acute phase inflammatory response due to alterations in visceral protein homeostasis regardless of nutritional status.…”

Effect of disease duration on the association between serum albumin and mucosal healing in patients with ulcerative colitis

“…Serum albumin is known as a marker of acute inflammation. 12 The serum albumin test is simple, rapid, relatively non-invasive, repeatable, and affordable, and can be measured at all medical institutions. There is abundant evidence regarding the association between serum albumin and clinical outcomes in patients with UC.…”