MON-119 APPLICATION OF GENDER SPECIFIC ULTRASONOGRAPHY CUT-OFFS TO DETERMINE RISK OF PROTEIN ENERGY WASTING IN HEMODIALYSIS PATIENTS

Abstract

Muscle depletion in hemodialysis (HD) patients associates with protein energy wasting (PEW) but quantification of muscle mass is challenging in the outpatient HD setting. Quadriceps muscle thickness assessment by ultrasound imaging (UI) offers a potential surrogate measure for muscle mass, and we aimed to determine the applicability of gender specific UI cut-off values for identifying risk of PEW in HD patients. PEW risk assessment used the criteria set by International Society of Renal Nutrition and Metabolism (ISRNM), namely body mass index (BMI) <23 kg/m2, reduction >10% in mid-arm muscle circumference (MAMC) in relation to the 50th percentile of reference population, serum albumin <38 g/dL and dietary energy intake (DEI) <25 kcal/kg ideal body weight (IBW). Using a portable UI device, we measured the cross-sectional area of the quadriceps muscle namely rectus femoris (RFCSA) in 351 Malaysian HD patients participated in the on going multi-centered Palm Tocotrienol in Chronic Hemodialysis (PaTCH) screening study. Using receiving operating characteristic analysis, derived RFCSA cut-off values to identify patients at risk of PEW were <6.00 cm2 for men and <4.47 cm2 for women. Differences for PEW criteria and various nutritional parameters were examined based on gender specific categorization (men: <6.00cm2 vs >6.00cm2 and women: <4.47cm2 vs >4.47cm2). Mann-Whitney’s U tested continuous data while Chi-square tested categorical data. Both men (62%, p<0.001) and women (77%, p=0.003) with smaller RFCSA had a higher prevalence of PEW. As per PEW criteria, both men and women with smaller RFCSA had significantly poorer BMI (men: 21.08, IQR: 19.11-23.74kg/m2 vs 25.10, IQR: 22.96-27.50kg/m2, p<0.001; women: 20.54, IQR: 18.29-22.85 kg/m2 vs 25.49, IQR: 22.83-28.85 kg/m2, p<0.001) and MAMC (men: 22.74, IQR: 20.41-24.75cm vs 24.76, IQR: 23.58-26.36cm, p<0.001; women: 19.38 IQR: 17.73-22.45cm vs 23.57, IQR: 21.34-25.39cm, p<0.001). DEI was significantly lower only in men with RFCSA<6.00cm2 (22.53, IQR: 19.09-27.66kcal/kg IBW vs 25.67, IQR: 22.46-30.43kcal/kg IBW, p<0.001) but not in women (23.64, IQR: 20.16-29.34kcal/kg IBW vs 24.35, IQR: 20.90-28.18kcal/kg IBW, p>0.05). Irrespective of gender, significantly lower muscle and fat mass, handgrip strength, and higher Malnutrition-Inflammation Score (all p<0.05) were observed in patients with smaller RFCSA. Using gender-specific RFCSA cut-offs, the UI method enabled differential PEW identification based on ISRNM criteria, yet factoring heterogeneous body compositional differences mediated by gender.