Sarcopenia Index Is a Simple Objective Screening Tool for Malnutrition in the Critically Ill

Abstract

Background Reliable and valid tools to screen for malnutrition in the intensive care unit (ICU) remain elusive. The sarcopenia index (SI) [(serum creatinine/serum cystatin C) × 100], could be an inexpensive, objective tool to predict malnutrition. We evaluated the SI as a screening tool for malnutrition in the ICU and compared it with the modified‐NUTRIC score. Materials and Methods This was a historical cohort study of ICU patients with stable kidney function admitted to Mayo Clinic ICUs between 2008 and 2015. Malnutrition was defined by the Subjective Global Assessment. Diagnostic performance was evaluated with the area under the receiver operating characteristic curve (AUC) and multivariable logistic regression. Results Of the 398 included patients, 181 (45%) had malnutrition, with 34 (9%) scored as severely malnourished. The SI was significantly lower in malnourished patients than in well‐nourished patients (64 ± 27 vs 72 ± 25; P = 0.002), and reductions in SI corresponded to increased malnutrition severity (P = 0.001). As a screening tool, the SI was an indicator of malnutrition risk (AUC 0.61) and performed slightly better than the more complex modified‐NUTRIC score (AUC = 0.57). SI cutoffs of 101 and 43 had >90% sensitivity and >90% specificity, respectively, for the prediction of malnutrition. Patients with a low SI (≤43) had a significantly higher risk of mortality (HR = 2.61, 95% CI 1.06–6.48, P = 0.038). Conclusion The frequency of malnutrition was high in this critically ill population, and it was associated with a poor prognosis. The SI could be used to assess nutrition risk in ICU patients.

Sarcopenia index based on serum creatinine and cystatin C is associated with 3-year mortality in hospitalized older patients

“…In a retrospective study conducted in adult ICU patients, the SI was related to in-hospital and 90-day mortality 16 . Recently, another retrospective study also found that a lower SI was associated with a significantly higher risk of mortality among adult ICU patients 27 . Our finding that the SI was associated with long-term mortality among hospitalized older patients was in line with these findings.…”

“…As we aforementioned, due to the defects of current diagnostic methods for sarcopenia, the validation of a specific biomarker as the surrogate marker of sarcopenia is an attractive method 25 . As a newcomer in this field, the SI and a very similar biomarker (serum creatinine/cystatin C ratio) are of low cost, high accessibility, and repeatability 26 , therefore, they have been studied in different populations since being introduced in 2015 [16][17][18][19]27 . Only two previous studies addressed the association between the SI and mortality 16,27 .…”

“…As a newcomer in this field, the SI and a very similar biomarker (serum creatinine/cystatin C ratio) are of low cost, high accessibility, and repeatability 26 , therefore, they have been studied in different populations since being introduced in 2015 [16][17][18][19]27 . Only two previous studies addressed the association between the SI and mortality 16,27 . In a retrospective study conducted in adult ICU patients, the SI was related to in-hospital and 90-day mortality 16 .…”

“…However, it is noteworthy that the predictive value of the SI for adverse outcomes does not necessarily mean that it can be applied as a surrogate marker of sarcopenia. In fact, the SI was applied as a malnutrition screening tool in a retrospective study conducted in Mayo Clinic ICU patients 27 . A previous study demonstrated that the SI correlated with CT-derived skeletal muscle mass in adult ICU patients 19 .…”

Incertidumbre clínica durante la prescripción de proteína al paciente en estado crítico de Latinoamérica

“…Vallejo y colaboradores reportaron que 74 % (n = 745/1053) de estos pacientes presentaban malnutrición de moderada a severa según la Evaluación Global Subjetiva (11) . Esta proporción es significativamente alta comparada con la observada (30 % -50 %) en estudios Norteamericanos y Europeos (12)(13)(14) . Dado que pacientes con deficiencias nutricionales preexistentes se pueden beneficiar más del apoyo nutricional artificial (15) , la literatura actual impide extender las recomendaciones actuales de prescripción de proteína al contexto latinoamericano debido a la falta de datos disponibles resultado de estudios procedentes de esta zona.…”