Comparison of bioimpedance and dual-energy x-ray absorptiometry for measurement of fat mass in hemodialysis patients

Muscularity and adiposity are differently associated with inflammatory and nutritional biomarkers among patients on hemodialysis and peritoneal dialysis

PURPOSE

Nutritional alterations are prevalent in patients undergoing hemodialysis (HD) and peritoneal dialysis (PD). We aimed at evaluating whether body composition parameters in HD vs PD are differently associated with nutritional and inflammatory biomarkers.

METHODS

Body composition was assessed by bioimpedance analysis. Neutrophil to lymphocyte ratio (NLR), serum albumin and C-reactive protein were used as nutritional and inflammatory biomarkers. Multivariable linear regression analysis was used to determine association(s) of body composition parameters with biomarkers.

RESULTS

We enrolled a total of 108 patients, 58 on HD and 50 on PD. Fat free mass percent was higher in HD patients than PD (p = 0.006) and higher extracellular water (ECW)/intracellular water (ICW) in HD compared to PD patients (p = 0.023), as well as fat mass index was greater in PD than HD (p = 0.004). In HD patients, albumin positively correlated with fat free mass (r = 0.42; p = 0.001) and ICW/h2 (r = 0.31; p = 0.02). In PD, NLR positively correlated with fat mass (r = 0.36; p = 0.01), fat mass index (r = 0.37; p = 0.01) and ECW (r = 0.41; p = 0.005), and negatively correlated with fat free mass percent (r = -0.30; p = 0.04) and ICW percent (r = -0.34; p = 0.02). By linear regression analysis, in HD fat free mass index was associated with albumin and the absence of diabetes. In PD, the association of fat free mass index was present with NLR. Regarding adiposity, in HD we found no association of ECW/ICW with NLR and CRP, whereas in PD the ECW/ICW was associated with NLR.

CONCLUSION

Inflammation drives body composition changes with differences according to the type of dialysis, as expressed by the modulation of some circulating biomarkers.

Measurement and optimization of perioperative risk among patients undergoing surgery for esophageal cancer

Esophagectomy is an exemplar of complex oncological surgery and is associated with a relatively high risk of major morbidity and mortality. In the modern era, where specific complications are targeted in prevention and treatment pathways, and where the principles of enhanced recovery after surgery are espoused, optimum outcomes are targeted via a number of approaches. These include comprehensive clinical and physiological risk assessment, specialist perioperative care by a high-volume team, and multimodal inputs throughout the patient journey that aim to preserve or restore nutritional deficits, muscle mass and function.

Serum irisin levels are negatively associated with blood pressure in dialysis patients

Elevated blood pressure is highly prevalent among dialysis patients and is associated with high mortality. Irisin is a newly found myokine that has been indicated to be related to blood pressure regulation in animal experiments. Data regarding the effect of serum irisin levels on blood pressure in dialysis patients are limited. To identify the association between serum irisin levels and blood pressure and examine determinant factors of systolic blood pressure in dialysis patients, we recruited 300 dialysis patients at Xuanwu Hospital Capital Medical University. Serum irisin levels were assessed by enzyme-linked immunosorbent assay kits. Blood pressure was self-measured on 7 consecutive days by an automated sphygmomanometer. The Pearson correlation test showed that the natural logarithm of irisin was negatively correlated with systolic blood pressure (r = -0.462, P < 0.001) and pulse pressure (r = -0.487, P < 0.001), but not correlated with diastolic blood pressure (r = -0.022, P = 0.709). Multivariate analysis revealed that the natural logarithm of irisin (β = -0.336, P < 0.001), lean tissue mass (β = 0.164, P = 0.005), diabetes mellitus (β = 0.165, P = 0.003) and serum calcium (β = -0.135, P = 0.019) were significant determinant factors for systolic blood pressure. This study is the first to demonstrate that serum irisin levels are significantly negatively associated with blood pressure in dialysis patients. Further studies are needed to provide possible mechanisms. We demonstrated that serum irisin levels were negatively associated with blood pressure in dialysis patients, which may provide a new target for antihypertensive treatment.

Is There a Need to "Modernize" and "Simplify" the Diagnostic Criteria of Protein-Energy Wasting?

Protein energy wasting(PEW) is a term that most nephrologists used to define nutritional disorders in patients with acute kidney injury and chronic kidney disease. Although this nomenclature is well implemented in the field of nephrology, the use of other terms such as cachexia or malnutritionin the majority of chronic diseases can induce confusion regarding the definition and interpretation of these terms. There is ample evidence in the literature that the pathways involved in cachexia/malnutrition and PEW are common. However, in kidney diseases, there are pathophysiological conditions such as accumulation of uremic toxins, and the use of dialysis, which may induce a phenotypic specificity justifying the original term PEW. In light of the latest epidemiologic studies, the criteria for PEW used in 2008 probably need to be updated. The objective of this review is to summarize the main mechanisms involved in cachexia/malnutrition and PEW. We discuss the need to modernize and simplify the current definition and diagnostic criteria of PEW. We consider the interest of proposing a specific nomenclature of PEW for children and elderly patients with kidney diseases.

Estimation of Muscle Mass in the Integrated Assessment of Patients on Hemodialysis

Assessment of muscle mass (MM) or its proxies, lean tissue mass (LTM) or fat-free mass (FFM), is an integral part of the diagnosis of protein-energy wasting (PEW) and sarcopenia in patients on hemodialysis (HD). Both sarcopenia and PEW are related to a loss of functionality and also increased morbidity and mortality in this patient population. However, loss of MM is a part of a wider spectrum, including inflammation and fluid overload. As both sarcopenia and PEW are amendable to treatment, estimation of MM regularly is therefore of major clinical relevance. Whereas, computer-assisted tomography (CT) or dual-energy X-ray absorptiometry (DXA) is considered a reference method, it is unsuitable as a method for routine clinical monitoring. In this review, different bedside methods to estimate MM or its proxies in patients on HD will be discussed, with emphasis on biochemical methods, simplified creatinine index (SCI), bioimpedance spectroscopy (BIS), and muscle ultrasound (US). Body composition parameters of all methods are related to the outcome and appear relevant in clinical practice. The US is the only parameter by which muscle dimensions are measured. BIS and SCI are also dependent on either theoretical assumptions or the use of population-specific regression equations. Potential caveats of the methods are that SCI can be influenced by residual renal function, BIS can be influenced by fluid overload, although the latter may be circumvented by the use of a three-compartment model, and that muscle US reflects regional and not whole body MM. In conclusion, both SCI and BIS as well as muscle US are all valuable methods that can be applied for bedside nutritional assessment in patients on HD and appear suitable for routine follow-up. The choice for either method depends on local preferences. However, estimation of MM or its proxies should always be part of a multidimensional assessment of the patient followed by a personalized treatment strategy.

Are we overfeeding hemodialysis patients with protein? Exploring an alternative method to estimate protein needs

BACKGROUND & AIMS

Sufficient protein intake is of great importance in hemodialysis (HD) patients, especially for maintaining muscle mass. Daily protein needs are generally estimated using bodyweight (BW), in which individual differences in body composition are not accounted for. As body protein mass is best represented by fat free mass (FFM), there is a rationale to apply FFM instead of BW. The agreement between both estimations is unclear. Therefore, the aim of this study is to compare protein needs based on either FFM or BW in HD patients.

METHODS

Protein needs were estimated in 115 HD patients by three different equations; FFM, BW and BW adjusted for low or high BMI. FFM was measured by multi-frequency bioelectrical impedance spectroscopy and considered the reference method. Estimations of FFM x 1.5 g/kg and FFM x 1.9 g/kg were compared with (adjusted)BW x 1.2 and x 1.5, respectively. Differences were assessed with repeated measures ANOVA and Bland-Altman plots.

RESULTS

Mean protein needs estimated by (adjusted)BW were higher compared to those based on FFM, across all BMI categories (P < 0.01) and most explicitly in obese patients. In females with BMI >30, protein needs were 69 ± 17.4 g/day higher based on BW and 45 ± 9.3 g/day higher based on BMI adjusted BW, compared to FFM. In males with BMI >30, protein needs were 51 ± 20.4 g/day and 23 ± 20.9 g/day higher compared to FFM, respectively.

CONCLUSIONS

Our data show large differences and possible overestimations of protein needs when comparing BW to FFM. We emphasize the importance of more research and discussion on this topic.

Using Bioimpedance Spectroscopy for Diagnosis of Malnutrition in Chronic Kidney Disease Stage 5-Is It Useful?

OBJECTIVE

Malnutrition is common in chronic kidney disease stage 5 (CKD5) and has negative clinical impacts. The aim of the present study is to evaluate bioimpedance spectroscopy (BIS) in diagnosing malnutrition in CKD5 including hemodialysis and peritoneal dialysis patients (CKD5D) using cutoff values for fat-free mass index (FFMI) according to the Global Leadership Initiative on Malnutrition criteria. Dual-energy X-ray absorptiometry (DXA) was used as a reference method.

DESIGN AND METHODS

We performed a single-center cross-sectional diagnostic study of 90 patients with CKD5 or CKD5D.

RESULTS

BIS-derived FFMI estimates were significantly higher compared with those obtained by DXA (18.5 ± 2.6 vs.17.8 ± 2.0, P < .05). The mean difference in FFMI estimates between the methods (DXA-BIS) and Bland-Altman 95% limits of agreements is -0.38 (2.76, -3.52) kg/m². Overhydration (B = 0.67, P < .001), age (B = 0.02, P = .037), and interactions between overhydration and CKD5 subgroups (P = .034) independently predicted bias in BIS-derived FFMI. BIS-derived FFMI showed poor sensitivity (64%) and positive predictive value (48%) in diagnosing malnutrition in the present study population.

CONCLUSION

The present study showed a limited agreement between estimates of FFMI derived by BIS and DXA due to a large interindividual variation. Using BIS as a clinical tool for assessing FFMI has limited accuracy and poor sensitivity in diagnosing malnutrition in patients with CKD5 and CKD5D.

Body Fat in Children with Chronic Kidney Disease - A Comparative Study of Bio-impedance Analysis with Dual Energy X-ray Absorptiometry

Introduction:

Nutritional impairment in patients with chronic kidney disease (CKD) is due to decreased body stores of both protein and fat. We need a tool that can be used in clinics to determine and monitor fat composition with a special focus on normalizing fat measurements to height in these children. Bio-impedance analysis (BIA), a portable and simple tool, has been used to estimate body fat in children with CKD but needs validation against the reference tool dual energy X-ray absorptiometry (DXA). The purpose of the cross-sectional study was to estimate the prevalence of low body fat in children with stages 2-5 CKD (non-dialysis) and CKD 5D (dialysis), and to compare fat measures from two different methods namely BIA and DXA.

Method:

Children in stages 2–5 CKD (n = 19) and in CKD 5D (n = 14) were recruited for assessment of fat mass (FM, Kg) by BIA and DXA, from which percent body fat (BF %) and fat mass index (FMI, Kg/M²) were obtained. Low body fat was defined as <5^th age and gender centile for BF% or FMI by DXA and BF% by BIA.

Results:

Low body fat was detected equally using BF% and FMI in 18% of children by DXA while only 12% were detected using BF% by BIA. In children with CKD2–5, a good degree of reliability was found with FMI measurements (ICC 0.76 CI [0.48,0.9]) and poor reliability in children with CKD 5D (ICC 0.58 CI [0.1,0.84]). BF% had poor to fair reliability in the children with CKD 2-5 and CKD 5D (ICC 0.64 [0.28,0.84] and 0.53 [0.02,0.82]), respectively. Comparing BF% and FMI obtained by BIA and DEXA, BIA overestimated BF% by 3.5% in comparison to DXA.

Conclusion:

In children with CKD, body fat is preserved in the majority. Among the two measures of fat, BF% estimated by BIA did not compare well with DXA while FMI measure was comparable with a lower bias. However, due to lack of reference values in Indian children for FMI obtained by BIA, BIA cannot be used to measure fat in this population.

Three compartment bioimpedance spectroscopy in the nutritional assessment and the outcome of patients with advanced or end stage kidney disease: What have we learned so far?

Bioimpedance spectroscopy (BIS) is an easily applicable tool to assess body composition. The three compartment model BIS (3C BIS) conventionally expresses body composition as lean tissue index (LTI) (lean tissue mass [LTM]/height in meters squared) and fat tissue index (FTI) (adipose tissue mass/height in meters squared), and a virtual compartment reflecting fluid overload (FO). It has been studied extensively in relation to diagnosis and treatment guidance of fluid status disorders in patients with advanced‐stage or end‐stage renal disease. It is the aim of this article to provide a narrative review on the relevance of 3C BIS in the nutritional assessment in this population. At a population level, LTI decreases after the start of hemodialysis, whereas FTI increases. LTI below the 10th percentile is a consistent predictor of outcome whereas a low FTI is predominantly associated with outcome when combined with a low LTI. Recent research also showed the connection between low LTI, inflammation, and FO, which are cumulatively associated with an increased mortality risk. However, studies toward nutritional interventions based on BIS data are still lacking in this population. In conclusion, 3C BIS, by disentangling the components of body mass index, has contributed to our understanding of the relevance of abnormalities in different body compartments in chronic kidney disease patients, and appears to be a valuable prognostic tool, at least at a population level. Studies assessing the effect of BIS guided nutritional intervention could further support its use in the daily clinical care for renal patients.

Chronic Kidney Disease and the Adiposity Paradox: Valid or Confounded?

OBJECTIVE

Obesity, defined by body mass index (BMI), is associated with lower mortality risk in patients with chronic kidney disease (CKD). BMI and % body fat (%BF) are confounded by muscle mass, while DXA derived fat mass index (FMI) overcomes this limitation. We compared the associations between obesity and mortality in persons with CKD using multiple estimates of adiposity, and determined whether muscle mass, inflammation and weight loss modify these associations.

METHODS

Obesity was defined using BMI and DXA-derived FMI and %BF cut-offs in 2,852 NHANES participants with CKD from 1999-2006 and linked to the National Death Index with follow up through 2011. Cox proportional hazards models assessed associations between mortality and measures of obesity.

RESULTS

Obesity based on FMI and continuous variables, FMI, BMI and %BF were associated with lower mortality. The protective association of obesity was less pronounced among participants with higher muscle mass and was no longer significant after adjustment for prior weight loss. Inflammation did not modify these associations.

CONCLUSIONS

We observed lower mortality associated with higher fat mass, particularly among persons with lower muscle mass. The prevalence of >10% weight loss was half as common among obese compared to non-obese participants and confounded these associations.

Serum levels of the adipokine zinc-alpha2-glycoprotein (ZAG) predict mortality in hemodialysis patients

Wasting has been associated with increased cardiovascular and all-cause mortality in chronic kidney disease (CKD). We investigated whether serum zinc-alpha2-glycoprotein (ZAG), a potent cachectic and lipid-mobilizing factor that is increased in patients with CKD, predicts clinical outcomes in patients on chronic hemodialysis. We quantified serum ZAG at baseline in a prospective cohort of 252 patients undergoing maintenance hemodialysis. Serum ZAG concentrations were inversely associated with serum albumin, creatinine, and triglycerides and, conversely, positively associated with age. Although ZAG is strongly linked to protein energy wasting (PEW) in patients with cancer, higher ZAG concentrations were not associated with PEW in our cohort. During a mean study follow-up of 954 days, 49 patients died and 62 patients experienced a cardiovascular event. Kaplan-Meier analysis revealed a significant correlation between serum ZAG concentrations and all-cause mortality and cardiovascular events. In separate multivariable Cox regression models, serum ZAG concentrations remained significantly associated with all-cause mortality and cardiovascular events after adjustment for demographic factors (age, sex, and dialysis vintage), metabolic parameters (serum albumin, prealbumin, triglycerides, cholesterol, normalized protein catabolic rate, and body mass index), and cardiovascular risk factors (diabetes, dyslipidemia, history of cardiovascular disease, smoking, and diuretic use as a proxy of residual renal function). Thus, serum ZAG appears to be a strong and independent predictor of mortality and cardiovascular events in patients with end-stage renal disease. Further studies are necessary to confirm this association and to elucidate the underlying mechanisms.

Associations of Body Mass Index and Body Fat With Markers of Inflammation and Nutrition Among Patients Receiving Hemodialysis

BACKGROUND

Understanding the extent to which visceral and subcutaneous body fat are associated with markers of nutrition and inflammation in patients on dialysis therapy could shed light on the obesity paradox and the biology of subcutaneous fat.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS

609 adults receiving hemodialysis who participated in the ACTIVE/ADIPOSE Study.

PREDICTORS

Body mass index (BMI), waist circumference, and bioelectrical impedance spectroscopy-derived estimates of percent body fat.

OUTCOMES

C-Reactive protein (CRP), interleukin 6 (IL-6), prealbumin, albumin, leptin, and adiponectin concentrations.

MEASUREMENTS

We performed linear regression analyses to examine the extent to which proxies of visceral and subcutaneous fat were associated with inflammation, nutrition, and adiposity-related hormones.

RESULTS

BMI was directly associated with markers of inflammation (standardized estimate for ln[CRP in mg/L]: 0.30 [95% CI, 0.22-0.38] per 10kg/m²; for ln[IL-6 in pg/mL]: 0.10 [95% CI, 0.02-0.18] per 10kg/m²), but was not associated with markers of nutrition. BMI was also inversely associated with adiponectin and directly associated with leptin. With waist circumference and percent body fat (as a proxy of visceral and subcutaneous fat, respectively) modeled together, waist circumference was associated with markers of inflammation (standardized estimate for ln[CRP in mg/L]: 0.21 [95% CI, 0.09-0.34] per 10cm; for ln[IL-6 in pg/mL]: 0.18 [95% CI, 0.07-0.29] per 10cm), whereas percent body fat was not associated with CRP (standardized estimate for ln[CRP in mg/L]: 0.03 [95% CI, -0.10 to 0.15] per 1%) and was inversely associated with IL-6 (standardized estimate for ln[IL-6 in pg/mL]: -0.15 [95% CI, -0.27 to -0.02] per 1%). In addition, waist circumference was inversely associated with prealbumin and albumin (standardized estimates of -0.12 [95% CI, -0.23 to -0.02] mg/dL per 10cm and -0.17 [95% CI, -0.28 to -0.06] g/dL per 10cm, respectively), and percent body fat was directly associated with prealbumin and albumin (0.20 [95% CI, 0.07-0.32] mg/dL and 0.15 [95% CI, 0.02-0.28] g/dL per 1%, respectively). Higher waist circumference was associated indirectly with adiponectin and directly with leptin concentrations.

LIMITATIONS

Although the observed associations implicate visceral fat as the cause of inflammation, it cannot be determined in this cross-sectional study.

CONCLUSIONS

Proxies of visceral and subcutaneous fat appear to have opposing associations with biomarkers of inflammation and nutrition. Subcutaneous fat may be an indicator of nutritional status, and visceral fat, an indicator of inflammation.

The Challenges of Nutritional Assessment in Cirrhosis

Purpose of Review

Nutritional status in patients with cirrhosis is very frequently associated with macro- and micronutrient deficiencies. Cirrhosis itself is the cause of malnutrition and nutritional deficiencies but these conditions have to be identified and addressed properly as they can worsen the prognosis of cirrhosis. The goals of this review are to 1) identify and describe the challenges associated with nutritional assessment in cirrhosis and 2) describe recent advancements when using clinical, laboratory, and instrumental tools in the evaluation of malnourished patients with liver diseases.

Recent Findings

The most promising tools for nutritional assessment in cirrhosis include the evaluation of body composition with phase angle obtained by bioelectrical impedance analysis, computed tomography transverse images at the level of third lumbar vertebra. The Royal-Free Hospital global assessment algorithm appears to be helpful but needs further validation.

Summary

Nutritional assessment in cirrhosis is challenging as several factors, including edema, can interfere with it and because of lack of a validated gold standard. Regardless, nutritional assessment methods have been developed in recent years and should gain relevance in the clinical practice.

Validating Body Fat Assessment by Bioelectric Impedance Spectroscopy in Taiwanese Hemodialysis Patients

OBJECTIVE

Obesity is becoming increasingly common in hemodialysis (HD) patients and is associated with inflammation and increased mortality. The primary aim of the present study was to evaluate the accuracy and variability of the bioimpedance device in measuring body fat in Taiwanese dialysis patients.

DESIGN

Cross-sectional study.

SUBJECTS

One hundred twenty-two adult patients receiving HD in a single hospital in Taiwan.

SETTING

We compared the results of fat mass (FM) measured by dual-energy x-ray absorptiometry (DEXA) and bioelectrical impedance spectroscopy device (Body composition monitor, BCM).

MAIN OUTCOME MEASUREMENT

FM measured by BCM was calculated by subtracting fat-free mass (FFM) from body mass assuming fractional hydration of FFM of 0.73 or the proprietary prediction equations from the BCM model.

RESULTS

Assessment of whole-body composition showed that percentage FM measured using the 2 techniques was highly correlated when using the BCM model or estimating from total body water using constant (0.73) hydration (r = 0.87, P < .001). There was no evident difference in measurement between patients gender. The Bland-Altman plot also showed good agreement of percentage of FM (t = 3.82; P < .001). In female patients, it was found that BCM significantly underestimated mean FM as compared to DEXA. However, the mean differences of the estimates between the methods were small (0.35 ± 3.00 kg) and with Bland-Altman plot the limits of agreements were -5.5 to 6.2 kg (P = .40) for FM in female patients.

CONCLUSIONS

Using DEXA as the reference test, BCM is a valid tool for the assessment of total body fat in HD patients. Hence, it may provide a more accessible tool for early detection of changes in body composition in these high-risk patients.

The metabolite beta-aminoisobutyric acid and physical inactivity among hemodialysis patients

OBJECTIVE

Physical inactivity is frequent in patients on hemodialysis (HD), and represents a reliable predictor of morbidity and mortality. Beta-aminoisobutyric acid (BAIBA) is a contraction-induced myokine, the plasma levels of which increase with exercise and are inversely associated with metabolic risk factors. The aim of this study was to ascertain whether physical inactivity and clinical parameters relate to plasma BAIBA levels in this patient population.

METHODS

Adult patients on HD were included, and the presence of physical inactivity was assessed. BAIBA levels were measured in these patients and in healthy individuals. We assessed barriers to physical activity, including 23 items regarding psychophysical and financial barriers. Body composition was assessed by bioimpedance and muscle strength by handgrip dynamometer. Nonparametric tests and logistic regression analyses were performed.

RESULTS

Forty-nine patients on HD were studied; 49% were physically active and 51% were inactive. Of the patients, 43 reported barriers to physical activity and 61% of inactive patients reported three or more barriers. BAIBA levels were lower in patients on HD with respect to controls (P < 0.001). Stratifying HD patients as active and inactive, both groups showed significantly lower BAIBA levels versus controls (P = 0.0005, P < 0.001, respectively). Nondiabetic patients on HD showed increased BAIBA levels compared with diabetic patients (P < 0.001). Patients on HD endorsing the two most frequent barriers showed lower BAIBA levels than those not reporting these barriers (P = 0.006). Active patients showed higher intracellular water (%) (P = 0.008), and active and inactive patients showed significant correlation between total body muscle mass and handgrip strength (P = 0.04, P = 0.005, respectively).

CONCLUSIONS

Physical inactivity is highly prevalent among patients on HD and BAIBA correlates with barriers to physical activity reported by inactive patients.

Association between body composition and frailty among prevalent hemodialysis patients: a US Renal Data System special study

Studies of frailty among patients on hemodialysis have relied on definitions that substitute self-reported functioning for measures of physical performance and omit weight loss or substitute alternate criteria. We examined the association between body composition and a definition of frailty that includes measured physical performance and weight loss in a cross-sectional analysis of 638 adult patients receiving maintenance hemodialysis at 14 centers. Frailty was defined as having three of following characteristics: weight loss, weakness, exhaustion, low physical activity, and slow gait speed. We performed logistic regression with body mass index (BMI) and bioelectrical impedance spectroscopy (BIS)-derived estimates of intracellular water (ICW), fat mass, and extracellular water (ECW) as the main predictors, and age, sex, race, and comorbidity as covariates. Overall, 30% of participants were frail. Older age (odds ratio [OR], 1.31 per 10 years; 95% confidence interval [95% CI], 1.14 to 1.50), diabetes (OR, 1.65; 95% CI, 1.13 to 2.40), higher fat mass (OR, 1.18; 95% CI, 1.02 to 1.37), and higher ECW (OR, 1.33; 95% CI, 1.20 to 1.47) associated with higher odds of frailty. Higher ICW associated with lower odds of frailty (OR, 0.80 per kg; 95% CI, 0.73 to 0.87). The addition of BMI data did not change the area under the receiver operating characteristics curve (AUC; AUC=0.66 versus 0.66; P=0.71), but the addition of BIS data did change the AUC (AUC=0.72; P<0.001). Thus, individual components of body composition but not BMI associate strongly with frailty in this cohort of patients receiving hemodialysis.