Phase Angle as Surrogate Marker of Muscle Weakness in Kidney Transplant Candidates Referred to Prehabilitation.

Phase angle (PhA), a marker of nutritional status obtained by bioelectrical impedance analysis (BIA), is associated with the integrity of cell membranes. Damage to muscle fiber membranes can impact muscle strength, which is related to adverse outcomes in adults with advanced chronic kidney disease (CKD). The main objective of this study was to determine the usefulness of the PhA in identifying muscle weakness in candidates for kidney transplants (KTs). Secondly, it aimed to examine the associations of PhA with other parameters of body composition, exercise performance, and muscle structure. Sensitivity, specificity, and area under the receiver operating characteristics curve were used to evaluate the PhA (index test) as a biomarker of muscle weakness. Muscle strength was estimated with maximal voluntary isometric contraction of the quadriceps (MVCI-Q) of the dominant side. Muscle weakness was defined as MVIC-Q < 40% of body weight. A total of 119 patients were evaluated (mean age 63.7 years, 75.6% men). A phase angle cut-off of 5.1° was identified to classify men with a higher likelihood of having low muscle strength in upper limbs (MVIC-Q 40% of their body weight). Male KT candidates with PhA < 5.1° had poorer exercise capacity, lower muscle strength, less muscle mass, and smaller muscle size. A PhA < 5.1° was significantly associated with an eight-fold higher muscle weakness risk (OR = 8.2, 95%CI 2.3-29.2) in a binary regression model adjusted by age, frailty, and hydration status. Remarkably, PhA is an easily obtainable objective parameter in CKD patients, requiring no volitional effort from the individual. The associations of PhA with aerobic capacity, physical activity, muscle mass, and muscle size underscore its clinical relevance and potential utility in the comprehensive evaluation of these patients.

Association between GLIM-defined malnutrition and hospitalizations in kidney transplant candidates: A post hoc analysis of a cohort study.

BACKGROUND: Malnutrition is frequent in patients with chronic kidney disease (CKD) and has a negative impact on morbidity, mortality, and quality of life. The objective of this study was to assess the value of the Global Leadership Initiative for Malnutrition (GLIM) criteria to predict hospitalizations and mortality in candidates to kidney transplant during their first year on the waiting list. METHODS: This was a post hoc analysis of 368 patients with advanced CKD. The main study variables were malnutrition, according to the GLIM criteria; number of hospital admissions during the first year on the waiting list; and mortality at the end of follow-up. Kaplan-Meier survival curves and binary logistic regression were performed, adjusting for age, frailty status, handgrip strength, and Charlson Index as potential confounders. RESULTS: The prevalence of malnutrition was 32.6%. Malnutrition was associated with increased risk of hospitalizations during the first year on the waiting list (odds ratio [OR] = 3.33 [95% CI = 1.34-8.26]), which persisted after adjustment for age and frailty status (adjusted OR = 3.61 [95% CI = 1.38-10.7]), age and handgrip strength (adjusted OR = 3.39 [95% CI = 1.3-8.85]), and age and Charlson Index (adjusted OR = 3.25 [95% CI = 1.29-8.13]). CONCLUSION: Malnutrition according to the GLIM criteria was highly prevalent in patients with CKD and was associated with a threefold increased risk of hospitalizations during the first year on the waiting list; these associations remained significant after adjusting for age, frailty status, handgrip strength, and comorbidities.

Fragilidad y estado nutricional en el periodo pre-trasplante. ¿Existe relación? / Frailty and nutritional status in the pre-transplant period. Is there a relationship?

Introducción: La malnutrición en la enfermedad renal crónica (ERC) está asociada al aumento del riesgo de mortalidad y complicaciones. Sin embargo, el estado nutricional de los pacientes con ERC en lista de espera (LE) de trasplante renal (TR), y su relación con el estado de fragilidad ha sido poco evaluado. Objetivo: Analizar el estado nutricional y funcional de una cohorte de pacientes en lista de espera de trasplante renal y su relación con la fragilidad. Pacientes y Método: Estudio retrospectivo de los pacientes incluidos en LE de TR desde Junio 2016 hasta Junio 2017. Se evaluaron a los pacientes mediante distintas escalas de valoración, recogiendo parámetros antropométricos, analíticos y de bioimpedanciometría (BCM). Resultados: De los 177 pacientes incluidos, 55 (31.1%) se definieron como frágiles. Dicho grupo eran de mayor edad (64.2 vs 61.2 años; p=0.08), sexo femenino (56.4% vs 32.8%, p<0.01), IMC mayor (29.3±5.8 vs 27.3±5,6 kg/m²; p=0.03) y más frecuentemente diabéticos (DM2) (43.6% vs 30.3%; p=0.08). La evaluación mediante BCM demostró que los pacientes frágiles tenían menos índice de tejido magro (12.3±2.4 vs 14.1±4 kg/m²; p<0.01) y mayor índice de tejido graso (16.2±6.1 vs 11.8±5.6 kg/m²; p<0.01) que los no frágiles. Conclusión: En nuestra lista de espera de TR, los pacientes frágiles son de mayor edad, sexo femenino, mayor grado de obesidad, DMII y con menor masa muscular. Las estrategias encaminadas a liberalizar dietas, aumentar la ingesta proteica y fomentar el ejercicio físico pueden ser relevantes para mejorar los resultados a corto y largo plazo del TR (AU)

Introduction: Malnutrition in chronic kidney disease (CKD) is associated with increased risk of mortality and complications. However, the nutritional status of patients with CKD on the renal transplant waiting list and their relationship to the frailty status has been poorly evaluated. Aim: To analyze the nutritional and functional status of a cohort of patients on the waiting list for renal transplantation and its relation to frailty. Patients and method: Retrospective study of patients included in waiting list of renal trasplantation from June 2016 to June 2017. Patients were evaluated through different assessment scales, taking anthropometric, analytical and bioimpedancometry (BCM) parameters. Results: Of the 177 patients included, 55 (31.1%) were defined as frailty. This frailty group was older (64.2 vs 61.2 years, p = 0.08), higher number of females (56.4% vs 32.8%, p <0.01), higher BMI (29.3 ± 5.8 vs 27.3 ± 5.6 kg / m², p = 0.03) and more frequently diabetic (DMII) (43.6% vs 30.3%, p = 0.08). The BCM evaluation showed that the frailty patients had a lower index of lean tissue (12.3 ± 2.4 vs 14.1 ± 4 kg / m², p <0.01) and a higher fat index (16.2 ± 6.1 vs 11.8 ± 5.6 kg / m²; <0.01) than non-frailty ones. Conclusions: In our waiting list for renal transplantation, the frailty patients are older, female, more obese, DMII and with lower muscle mass. Strategies to liberalize diets, increase protein intake and promote physical exercise may be relevant to improve the short- and long-term results of the renal transplantation (AU)