Ultrasound Cut-Off Values for Rectus Femoris for Detecting Sarcopenia in Patients with Nutritional Risk
Authors: de Luis Roman Daniel , García Almeida José Manuel , Bellido Guerrero Diego , Guzmán Rolo Germán , Martín Andrea , Primo Martín David , García-Delgado Yaiza , Guirado-Peláez Patricia , Palmas Fiorella , Tejera Pérez Cristina , García Olivares María , Maíz Jiménez María , Bretón Lesmes Irene , Alzás Teomiro Carlos Manuel , Guardia Baena Juan Manuel , Calles Romero Laura A. , Prior-Sánchez Inmaculada , García-Luna Pedro Pablo , González Pacheco María , Martínez-Olmos Miguel Ángel , Alabadí Blanca , Alcántara-Aragón Valeria , Palma Milla Samara , Martín Folgueras Tomás , Micó García Andrea , Molina-Baena Begoña , Rendón Barragán Henry , Rodríguez de Vera Gómez Pablo , Riestra Fernández María , Jiménez Portilla Ana , López-Gómez Juan J. , Pérez Martín Nuria , Montero Madrid Natalia , Zabalegui Eguinoa Alba , Porca Fernández Cristina , Tapia Guerrero María José , Ruiz Aguado Marta , Velasco Gimeno Cristina , Herrera Martínez Aura D , Novo Rodríguez María , Iglesias Hernández Natalia C. , de Damas Medina María , González Navarro Irene , Vílchez López Francisco Javier , Fernández-Pombo Antía , Olveira Gabriel 
Published: May 2024

Background: A nationwide, prospective, multicenter, cohort study (the Disease-Related caloric-protein malnutrition EChOgraphy (DRECO) study) was designed to assess the usefulness of ultrasound of the rectus femoris for detecting sarcopenia in hospitalized patients at risk of malnutrition and to define cut-off values of ultrasound measures. Methods: Patients at risk of malnutrition according to the Malnutrition Universal Screening Tool (MUST) underwent handgrip dynamometry, bioelectrical impedance analysis (BIA), a Timed Up and Go (TUG) test, and rectus femoris ultrasound studies. European Working Group on Sarcopenia in Older People (EWGSOP2) criteria were used to define categories of sarcopenia (at risk, probable, confirmed, severe). Receiver operating characteristic (ROC) and area under the curve (AUC) analyses were used to determine the optimal diagnostic sensitivity, specificity, and predictive values of cut-off points of the ultrasound measures for the detection of risk of sarcopenia and probable, confirmed, and severe sarcopenia. Results: A total of 1000 subjects were included and 991 of them (58.9% men, mean age 58.5 years) were evaluated. Risk of sarcopenia was detected in 9.6% patients, probable sarcopenia in 14%, confirmed sarcopenia in 9.7%, and severe sarcopenia in 3.9%, with significant differences in the distribution of groups between men and women (p < 0.0001). The cross-sectional area (CSA) of the rectus femoris showed a significantly positive correlation with body cell mass of BIA and handgrip strength, and a significant negative correlation with TUG. Cut-off values were similar within each category of sarcopenia, ranging between 2.40 cm2 and 3.66 cm2 for CSA, 32.57 mm and 40.21 mm for the X-axis, and 7.85 mm and 10.4 mm for the Y-axis. In general, these cut-off values showed high sensitivities, particularly for the categories of confirmed and severe sarcopenia, with male patients also showing better sensitivities than women. Conclusions: Sarcopenia in hospitalized patients at risk of malnutrition was high. Cut-off values for the better sensitivities and specificities of ultrasound measures of the rectus femoris are established. The use of ultrasound of the rectus femoris could be used for the prediction of sarcopenia and be useful to integrate nutritional study into real clinical practice.