Decreased abdominal wall muscle mass defined by muscle ultrasound is associated with malnutrition according to Global Leadership Initiative on Malnutrition criteria in renal transplant recipients: A cross-sectional study.

Background: Changed body composition with increased fat content and decreased muscle mass is seen in renal transplantation recipients (RTRs). Increased fat mass might mask underlying muscle mass loss; measuring low body mass index and weight reduction alone may not be sensitive enough to diagnose malnutrition in RTRs. We aimed to determine the prevalence of malnutrition in stable RTRs using the Global Leadership Initiative on Malnutrition (GLIM) criteria and to assess the use of muscle ultrasonography (US) to compare the performance of various muscle US measurements in the diagnosis of reduced muscle mass.

Methods: Ninety-one patients who had renal transplantation >6 months ago were enrolled in the study. GLIM criteria were performed for all patients, but not those at risk of malnutrition. Bioelectrical impedance analysis and muscle US were performed to identify reduced muscle mass.

Results: The prevalence of malnutrition according to GLIM criteria was 25.3% (n = 23). All muscle US measurements were lower in the malnourished group than the well-nourished group; however, the malnourished group had substantially lower muscle thicknesses in abdominal muscles, specifically the external oblique (EO) and internal oblique (IO) muscles, than the well-nourished group (P = 0.001 and P = 0.007, respectively). There was a significant association between malnutrition and EO (odds ratio [OR] = 0.338, 95% CI = 0.163-0.699; P = 0.003) and IO (OR = 0.620, 95% CI = 0.427-0.900; P = 0.012) regardless of age and sex.

Conclusion: One in four RTRs experience malnutrition. Muscle US could be used effectively for the diagnosis of reduced muscle mass and malnutrition in RTRs according to GLIM criteria.