Dietary needs, barriers, and facilitators among patients on hemodialysis and their caregivers: The GoodRENal Project in Spain.

OBJECTIVE: Dietary restrictions are common in patients undergoing hemodialysis (HD). These restrictions result in a complex diet that becomes difficult for patients to understand and to follow. Therefore, we aimed to identify dietary needs, and barriers and facilitators that influence the adherence to dietary recommendations as perceived by patients on HD and their caregivers. METHODS: Seventy-two Spanish patients on HD and fifty-seven caregivers participated in this explorative study by replying a questionnaire consisting of 20 and 10 questions respectively. The responses were assessed using a Likert scale varying from 1 to 5 (strongly agree, agree, neither disagree or disagree, disagree, strongly disagree, respectively) to evaluate the perception of patients and caregivers regarding dietary needs, barriers and facilitators to adhere to the recommended diet. For analysis purposes, the responses were grouped in three categories (agree, neither agree or disagree, disagree). RESULTS: Seventy percent of the patients agreed that knowing the food sources of potassium, protein and phosphate was a need for them to know to be able to adhere to the dietary recommendations. Moreover, patients stated that not being able to eat what they liked, and feeling thirsty, were important barriers. For caregivers, the support of a renal dietitian was mentioned as an important facilitator to assist those they cared for to adhere to the diet. CONCLUSIONS: Knowing food sources of potassium, phosphate, and protein, exploring foods patients like to eat and adjusting fluid intake to avoid feeling thirsty were identified as important by the patients. These findings can be used to develop strategies and educational material to improve the dietary adherence in patients undergoing HD. Moreover, the presence of a renal dietitian was identified as an important resource by the caregivers.

Nutritional Status of Patients Starting on Peritoneal Dialysis: A Comparison Between Planned and Unplanned Dialysis Initiation.

OBJECTIVE: A suboptimal dialysis initiation with insufficient or no planning before urgent start of dialysis remains a common problem associated with increased morbimortality. Whether nutritional markers differ between patients starting peritoneal dialysis (PD) in unplanned and planned modes has not yet been explored. Therefore, we aimed to evaluate whether the nutritional status at the start of dialysis differed between patients with unplanned and planned PD initiation. METHODS: In this observational study comprising 47 adult patients starting PD (age 58 ± 15 years, 51% female), 29 patients had unplanned (starting dialysis up to 72 hours after peritoneal catheter implantation) and 18 planned (follow-up predialysis >90 days) dialysis initiation. Within 30 days of PD initiation, nutritional status was evaluated using anthropometric measurements, multifrequency bioelectrical impedance analysis, appetite assessment, handgrip strength, laboratory markers, and the malnutrition-inflammation score. Physical activity and performance were also evaluated. RESULTS: Patients with an unplanned PD initiation had a higher frequency of diabetes, higher blood glucose, urea, and glycated hemoglobin levels, and lower hemoglobin and albumin levels. Furthermore, they had a lower calf circumference, slower gait speed, higher protein intake, and greater malnutrition-inflammation score, while their physical activity level and appetite did not differ. CONCLUSION: Patients with an unplanned PD had unfavorable clinical and nutritional markers compared with those with planned PD. These findings indicate that a lack of follow-up prior to dialysis initiation can influence the clinical and nutritional statuses of patients, reinforcing the importance of conservative treatment prior to dialysis initiation.

Needs, barriers and facilitators for a healthier lifestyle in haemodialysis patients: The GoodRENal project.

BACKGROUND: Malnutrition, sedentary lifestyle, cognitive dysfunction and poor psychological well-being are often reported in patients on haemodialysis (HD). AIMS: We aimed to explore needs, barriers and facilitators-as perceived by patients, their carers, and healthcare professionals (HCPs) for increasing the adherence to the diet, to physical activity and cognition and psychological well-being. METHODS: This is an observational cross-sectional study following the STROBE statement. This study is part of an ERASMUS+ project, GoodRENal-aiming to develop digital tools as an educational approach to patients on HD. For that, the GoodRENal comprises HD centers located in four Belgium, Greece, Spain and Sweden. Exploratory questionnaires were developed regarding the perceived needs, barriers and facilitators regarding the diet, physical activity, cognition and psychological well-being from the perspective of patients, their carers and HCPs. RESULTS: In total, 38 patients, 34 carers and 38 HCPs were included. Nutrition: For patients and carers, the main needs to adhere to the diet included learning more about nutrients and minerals. For patients, the main barrier was not being able to eat what they like. Physical activity: As needs it was reported information about type of appropriate physical activity, while fatigue was listed as the main barrier. For Cognitive and emotional state, it was perceived as positive for patients and carers perception but not for HCPs. The HCPs identified as needs working as a team, having access to specialised HCP and being able to talk to patients in private. CONCLUSIONS: Patients and their carers listed as needs guidance regarding nutrition and physical activity but were positive with their cognitive and emotional state. The HCPs corroborated these needs and emphasised the importance of teamwork and expert support.

Design and methodology of the SARCopenia trajectories and associations with adverse clinical outcomes in patients on HemoDialysis: the SARC-HD study.

BACKGROUND: Sarcopenia has been associated with adverse outcomes in patients with chronic kidney disease (CKD), particularly in those undergoing hemodialysis (HD). However, the trajectories across sarcopenia stages, their determinants, and associations with adverse clinical outcomes have yet to be comprehensively examined. METHODS: The SARC-HD is a multicenter, observational prospective cohort study designed to comprehensively investigate sarcopenia in patients on HD. Eligibility criteria include adult patients undergoing HD for ≥ 3 months. The primary objective is to investigate the trajectories of sarcopenia stages and their potential determinants. Secondary objectives include evaluating the association between sarcopenia and adverse clinical outcomes (i.e., falls, hospitalization, and mortality). Sarcopenia risk will be assessed by the SARC-F and SARC-CalF questionnaire. Sarcopenia traits (i.e., low muscle strength, low muscle mass, and low physical performance) will be defined according to the revised European Working Group on Sarcopenia in Older People and will be assessed at baseline and after 12 follow-up months. Patients will be followed-up at 3 monthly intervals for adverse clinical outcomes during 24 months. DISCUSSION: Collectively, we expect to provide relevant clinical findings for healthcare professionals from nephrology on the association between sarcopenia screening tools (i.e., SARC-F and SARC-CalF) with objective sarcopenia measurements, as well as to investigate predictors of trajectories across sarcopenia stages, and the impact of sarcopenia on adverse clinical outcomes. Hence, our ambition is that the data acquired from SARC-HD study will provide novel and valuable evidence to support an adequate screening and management of sarcopenia in patients on HD.

Planetary Health, Nutrition, and Chronic Kidney Disease: Connecting the Dots for a Sustainable Future.

The increasing consumption of ultra-processed food (UPF) and the global chain of food production have a negative impact on human health and planetary health. These foods have been replacing the consumption of nonprocessed healthy foods. This shift has not only worsened human health by increasing the risk of the development of noncommunicable diseases, but also resulted in environmental perturbations. This review aims to bring awareness of the problems caused by the industrialized food production chain, addressing the negative effects it has on the environment and human health, with special reference to chronic kidney disease (CKD). We discuss possible solutions focusing on the benefits of adopting plant-based diets with low UPF content to promote a sustainable and healthy food production and diet for patients with CKD. For a sustainable future we need to "connect the dots" of planetary health, food production, and nutrition in the context of CKD.

New Insights Into Dietary Approaches to Potassium Management in Chronic Kidney Disease.

Potassium disorders are one of the most common electrolyte abnormalities in patients with chronic kidney disease (CKD), contributing to poor clinical outcomes. Maintaining serum potassium levels within the physiologically normal range is critically important in these patients. Dietary potassium restriction has long been considered a core strategy for the management of chronic hyperkalemia in patients with CKD. However, this has been challenged by recent evidence suggesting a paradigm shift toward fostering more liberalized, plant-based dietary patterns. The advent of novel potassium binders and an improved understanding of gastrointestinal processes involved in potassium homeostasis (e.g., gastrointestinal potassium wasting) may facilitate a paradigm shift and incorporation of heart-healthy potassium-enriched food sources. Nevertheless, uncertainty regarding the risk-benefit of plant-based diets in the context of potassium management in CKD remains, requiring well-designed clinical trials to determine the efficacy of dietary potassium manipulation toward improvement of clinical outcomes in patients with CKD.

A Comparative Analysis of Nutritional Assessment Using Global Leadership Initiative on Malnutrition Versus Subjective Global Assessment and Malnutrition Inflammation Score in Maintenance Hemodialysis Patients.

OBJECTIVE: Malnutrition is a prevalent condition in maintenance hemodialysis (MHD) patients. This study aimed to evaluate the performance of the recently developed GLIM (Global Leadership Initiative on Malnutrition) in MHD by assessing the agreement, accuracy, sensitivity, specificity, and survival prediction of GLIM when compared to 7-point subjective global assessment (7p-SGA) and malnutrition inflammation score (MIS). DESIGN AND METHODS: We investigated 2 cohorts: MHDltaly (121 adults from Italy; 67 ± 16 years, 65% men, body mass index 25 ± 5 kg/m2) and MHDBrazil (169 elderly [age > 60 years] from Brazil; 71 ± 7 years, 66% men, body mass index 25 ± 4 kg/m2), followed for all-cause mortality for median 40 and 17 months, respectively. We applied the 2-step approach from GLIM: (1) screening and (2) confirming malnutrition by phenotypic and etiologic criteria. For 7p-SGA and MIS, a score ≤5 and ≥8, respectively, defined malnutrition. RESULTS: Malnutrition was present in 38.8% by GLIM, 25.6% by 7p-SGA, and 29.7% by MIS in the MHDItaly cohort, and in 47.9% by GLIM, 59.8% by 7p-SGA, and 49.7% by MIS in the MHDBrazil cohort. Cohen's kappa coefficient (κ) showed only "fair" agreement between GLIM and SGA (MHDItaly: κ = 0.26, P = .003; MHDBrazil: κ = 0.22, P = .003) and between GLIM and MIS (MHDItaly: κ = 0.33, P < .001; MHDBrazil: κ = 0.25, P = .001). Cox regression analysis showed that all 3 methods were able to predict mortality in crude analysis; however in the adjusted model, the association seemed more consistent and stronger in magnitude for 7p-SGA and MIS. CONCLUSION: In MHD patients, GLIM showed low agreement, sensitivity, and accuracy in identifying malnourished subjects by either 7p-SGA or MIS. Considering the specific wasting characteristics that predominate in MHD, the well-established 7p-SGA and MIS methods may be more useful in this clinical setting.

Strategies designed to increase the motivation for and adherence to dietary recommendations in patients with chronic kidney disease.

Chronic kidney disease (CKD) often requires several dietary adjustments to control the disease-related disturbances. This is challenging for both patients and healthcare providers, and particularly for dietitians, who deal closely with the poor adherence to dietary recommendations. Factors associated with poor adherence within the CKD scenario and the need for a shift in the paradigm have already been indicated in several studies; however, rarely are any different and/or potential strategies actually formulated in order to change this paradigm. In this review, we aimed to explore the concepts and factors surrounding adherence to dietary recommendations in CKD and further describe certain potential strategies for a nutritional counseling approach. Such strategies, while poorly explored within CKD, have shown positive results in other chronic disease scenarios. It is timely, therefore, for healthcare providers to acquire these new counseling skills; nevertheless, this would require a rethinking of the traditional attitudes and approaches in order to build a partnership, based on a nonjudgmental and compassionate style in order to guide behavior change. The reflections presented in this review may contribute towards enhancing motivation and the adherence to dietary recommendations in CKD patients.

Food Consumption in Chronic Kidney Disease: Association With Sociodemographic and Geographical Variables and Comparison With Healthy Individuals.

OBJECTIVE: To describe the food consumption of individuals with chronic kidney disease (CKD) per sociodemographic and geographical characteristics and CKD treatment. In addition, we compared the food consumption of individuals with and without CKD. METHODS: Cross-sectional study using data from the National Health Survey (Brazil 2013) that included 60,202 individuals. Food consumption was evaluated with the following food intake markers: (1) regular consumption of fruit, vegetables, beans, milk, sugar-sweetened beverages (SSBs), sweets, red meat, and chicken; (2) weekly intake of fish; and (3) consumption of meat or chicken with excess fat, excess salt, and alcoholic beverage. The prevalence of these indicators was described per sociodemographic (gender, age, educational level, and race/skin color) and geographical (location of residence and geographical regions) variables in CKD and non-CKD individuals. Unadjusted and multiple logistic regression models, adjusted by sociodemographic and geographical variables, were applied. RESULTS: 60,202 individuals were divided into 5 groups: (1) non-CKD (n 5 59,363), (2) non-dialysis-dependent (n 5 480), (3) dialysis (n 5 48), (4) renal transplanted (n 5 17), and (5) untreated CKD (n 5 294). Age, education level, and geographic region were associated with food markers. Comparisons among those with CKD by treatment group showed that the dialysis group had a lower regular consumption of beans, alcoholic beverages, and salt in excess. Upon further comparisons with the non-CKD group, the CKD group (especially that in dialysis) showed a significantly lower regular consumption of beans, red meat, SSBs, salt in excess, and alcoholic beverages. Except for SSBs, this difference was maintained after adjustment. CONCLUSIONS: Food consumption of the CKD individuals is influenced by sociodemographic and geographical characteristics. Food groups of which patients are normally advised to limit their dietary intake were those with the greatest difference between individuals with and without CKD and among the CKD treatments.

Factors Associated with Sarcopenia in Patients with Colorectal Cancer.

Introduction; Sarcopenia are frequently observed in cancer patients and was associated with poor prognosis. Objectives; to determine the association of nutritional status, body composition, and clinic parameters with sarcopenia in patients with colorectal cancer (CRC). Methods; We conducted a cross-sectional study of 197 patients with CRC. The sarcopenia elements, including lumbar skeletal muscle index (SMI), handgrip strength, and gait speed were measured. The SMI was assessed by computed tomography at third lumbar vertebra. Phase angle (PA), serum albumin (SAlb), muscle attenuation (MA), and the scored patient-generated subjective global assessment (PG-SGA) were also evaluated. Univariate and multivariate analysis of factors associated with sarcopenia were performed. Results; Sarcopenia was present in 29 of 195 patients (15%) and was significantly correlated with advance age, lower body mass index (BMI), SAlb, PA, MA, higher PG-SGA score, and malnutrition (PG-SGA B). In univariate analysis, age, BMI, SAlb, PA, MA, PG-SGA score, and malnutrition (PG-SGA B) were associated with sarcopenia. Multivariable analysis revealed that BMI, SAlb, PA, MA, and PG-SGA score were independent predictors of sarcopenia. Conclusion; BMI, SAlb, PA, MA, and PG-SGA score were independent predictors of sarcopenia in patients with CRC.

Association of Sarcopenia With Nutritional Parameters, Quality of Life, Hospitalization, and Mortality Rates of Elderly Patients on Hemodialysis.

OBJECTIVE: This study aimed to assess whether diminished muscle mass, diminished muscle strength, or both conditions (sarcopenia) are associated with worse nutritional status, poor quality of life (QoL), and hard outcomes, such as hospitalization and mortality, in elderly patients on maintenance hemodialysis (MHD). DESIGN AND SUBJECTS: This is a multicenter observational longitudinal study that included 170 patients on MHD (age 70 ± 7 years, 65% male) from 6 dialysis centers. MAIN OUTCOME MEASURE: The European Working Group on Sarcopenia in Older People defines sarcopenia as the presence of both low muscle mass by appendicular skeletal + low muscle function by handgrip strength. This study evaluated the clinical and nutritional status (laboratory, anthropometry, dual-energy X-ray absorptiometry, 7-point subjective global assessment) and QoL (Kidney Disease Quality of Life) at baseline. Hospitalization and mortality were recorded during 36 months. RESULTS: Reduced muscle mass was observed in 64% of the patients, reduced muscle strength in 52%, and sarcopenia in 37%. The group with sarcopenia was older, had a higher proportion of men and showed worse clinical and nutritional conditions when compared with patients without sarcopenia. Although reduced muscle mass was strongly associated with poor nutritional status, low muscle strength was associated with worse QoL domains. In the multivariate Cox analyses adjusted by age, gender, dialysis vintage, and diabetes mellitus, low muscle strength alone and sarcopenia were associated with higher hospitalization, and sarcopenia was a predictor of mortality. CONCLUSION: In conclusion, in this sample, comprised of elderly patients on MHD, sarcopenia was associated with worse nutritional and clinical conditions and was a predictor of hospitalization and mortality.

Nutritional assessment of elderly patients on dialysis: pitfalls and potentials for practice.

The chronic kidney disease (CKD) population is aging. Currently a high percentage of patients treated on dialysis are older than 65 years. As patients get older, several conditions contribute to the development of malnutrition, namely protein energy wasting (PEW), which may be compounded by nutritional disturbances associated with CKD and from the dialysis procedure. Therefore, elderly patients on dialysis are vulnerable to the development of PEW and awareness of the identification and subsequent management of nutritional status is of importance. In clinical practice, the nutritional assessment of patients on dialysis usually includes methods to assess PEW, such as the subjective global assessment, the malnutrition inflammation score, and anthropometric and laboratory parameters. Studies investigating measures of nutritional status specifically tailored to the elderly on dialysis are scarce. Therefore, the same methods and cutoffs used for the general adult population on dialysis are applied to the elderly. Considering this scenario, the aim of this review is to discuss specific considerations for nutritional assessment of elderly patients on dialysis addressing specific shortcomings on the interpretation of markers, in addition to providing clinical practice guidance to assess the nutritional status of elderly patients on dialysis.

A practical approach to dietary interventions for nondialysis-dependent CKD patients: the experience of a reference nephrology center in Brazil.

This paper describes the 30-year experience on nutritional management of non-dialysis dependent chronic kidney disease (CKD) patients in a public outpatient clinic located in the city of São Paulo, Brazil. A team of specialized dietitians in renal nutrition is responsible to provide individual dietary counseling for patients on stages 3 to 5 of CKD. Two different types of nutrition care protocols are employed depending on the level of renal function. For patients with CKD stage 3 a simplified nutritional assessment is performed and the main dietary focus is on the control of protein intake particularly from animal sources. A more complete nutritional assessment as well as a detailed dietary plan focusing not only on the control of protein but also on energy supply and on specific micronutrients is provided for patients on stages 4 or 5 of CKD. Practical approaches and tools used by the dietitians in our clinic for improving patient´s adherence to protein, sodium and potassium restriction while maintaining a healthy diet are described in detail in the sections of the article.

Sensitivity and Specificity of Body Mass Index as a Marker of Obesity in Elderly Patients on Hemodialysis.

OBJECTIVES: Diagnosing obesity by body mass index (BMI) may not be reliable in elderly individuals due to the changes in body composition. We aimed to analyze the accuracy of BMI thresholds by World Health Organization (WHO) and Nutrition Screening Initiative (NSI) to diagnose obesity in elderly patients on hemodialysis (HD). DESIGN: Multicenter cross-sectional study. SETTING: Six dialysis facilities. SUBJECTS: 169 elderly on chronic HD (70.4 ± 7.1 years; 63.9% men). MAIN OUTCOME VARIABLE: Total body fat percentage (BF%) was assessed by the sum of skinfold thicknesses and abdominal fat by waist circumference (WC). Both were used as reference to test the specificity and sensitivity of BMI thresholds (WHO: ≥30 kg/m(2); NSI: >27 kg/m(2)). RESULTS: The prevalence of obesity according to NSI-BMI, WHO-BMI, BF%, and WC thresholds were 31%, 13%, 27%, and 29.6% in men, respectively, and 36%, 15%, 13%, and 75% in women. Compared to BF%, the sensitivity of NSI-BMI was moderate (65.5%) for men and high (100%) for women, whereas that of WHO-BMI was low (31%) for men and high (87.5%) for women. Compared with WC, NSI-BMI had good (75%) sensitivity for men and moderate (47.8%) for women, whereas WHO-BMI had moderate (43.8%) sensitivity for men and low (19.6%) for women. The best agreement with BF% was observed for NSI-BMI in men (kappa = 0.46) and for WHO-BMI in women (kappa = 0.80). For WC, the best agreement was for WHO-BMI for men (kappa = 0.63) and NSI-BMI for women (kappa = 0.31). CONCLUSIONS: BMI thresholds do not accurately diagnose adiposity in elderly on HD. Therefore, using BMI may lead to misclassifications in this segment population.

Concurrent and Predictive Validity of Composite Methods to Assess Nutritional Status in Older Adults on Hemodialysis.

OBJECTIVE: To assess the performance of subjective global assessment (SGA), malnutrition inflammation score (MIS), and mini nutritional assessment short-form (MNA-SF) in older adults on hemodialysis (HD) by evaluating their concurrent and predictive validity. DESIGN: An observational and prospective study including older adults on HD. SETTING: Six dialysis units. SUBJECTS: We assessed 137 HD patients aged ≥60 years (71.7% male, 70.2 ± 7.2 years). MAIN OUTCOME MEASURES: The nutritional status was assessed by 7-point SGA, MIS and MNA-SF, and by objective methods. Patients were followed up for 14.5 (8; 26.3) months (median and interquartile) to assess survival. RESULTS: Protein energy wasting (PEW) was present in 63% of the patients when assessed by SGA, in 77% by MIS, and in 26% by MNA-SF. Most objective parameters of patients classified with PEW were lower (P < .05) than those from patients classified as well-nourished by SGA, MIS, and MNA-SF. In addition, the hazard of death was higher for patients classified as PEW by SGA (hazard ratio 2.63 [95% confidence interval 1.14-6.00]), MIS (5.13 [1.19-13.7]), and MNA-SF (2.53 [1.34-4.77]) in comparison to well-nourished patients. CONCLUSIONS: The prevalence of PEW varied depending on the tool applied. SGA, MIS, and MNA-SF had good concurrent and predictive validity for the assessment of nutritional status, but SGA and MIS were likely to perform better than MNA-SF.

Pros and cons of body mass index as a nutritional and risk assessment tool in dialysis patients.

Obesity is a problem of serious concern among chronic kidney disease (CKD) patients; it is a risk factor for progression to end-stage renal disease and its incidence and prevalence in dialysis patients exceeds those of the general population. Obesity, typically assessed with the simple metric of body mass index (BMI), is considered a mainstay for nutritional assessment in guidelines on nutrition in CKD. While regular BMI assessment in connection with the dialysis session is a simple and easy-to-use monitoring tool, such ease of access can lead to excess-of-use, as the value of this metric to health care professionals is overestimated. This review examines BMI as a clinical monitoring tool in CKD practice and offers a critical appraisal as to what a high or a low BMI may signify in this patient population. Topics discussed include the utility of BMI as a reflection of body size, body composition and body fat distribution, diagnostic versus prognostic performance, and consideration of temporal trends over single assessments.

Food intake assessment of elderly patients on hemodialysis.

OBJECTIVE: To investigate whether the dietary intake of elderly patients on hemodialysis (HD) is lower than that of elderly individuals with normal renal function. In addition, we also assessed whether the dietary intake of elderly on HD is lower on the dialysis day (DD) than on nondialysis days (non-DD). DESIGN: A cross-sectional and observational study including elderly on HD and non-chronic kidney disease (non-CKD) elderly. SUBJECTS: We assessed 54 noninstitutionalized elderly patients on HD (study group) and 47 non-CKD elderly (control group) aged ≥60 years. MAIN OUTCOME MEASURES: All participants had their dietary intake assessed by 3-day food diaries. As a sensitivity analysis, we also assessed the dietary intake in the adequate reporters, which were identified when the ratio-energy intake-to-estimated basal metabolic rate-was above 1.27 (Goldberg index). RESULTS: When comparing dietary intake between the study and control groups, adjusted for sex and underreporting, it was noted that only the intake of protein (ß: -9.9; P: .01) and phosphorus (ß: -104; P: .04) were significantly lower in the study group. In addition, when furthering the analysis in the study group by comparing DD with non-DD, it was observed that energy (18 ± 7 vs. 21 ± 8 kcal/kg/day), protein (0.8 ± 0.4 vs. 1.0 ± 0.4 g/kg/day), lipids (41 ± 20 vs. 48 ± 23 g/day), potassium (1371 ± 587 vs. 1540 ± 484 mg/day), and phosphorous intake (647 ± 312 vs. 789 ± 287 mg/day), but not carbohydrate (155 ± 54 vs. 167 ± 55 g/day) and calcium (470 ± 345 vs. 518 ± 333 g/day) were significantly lower on DDs than on non-DDs, respectively. CONCLUSIONS: Except for protein and phosphorous, energy and nutrient intake of elderly patients on HD are similar to that of non-CKD elderly. In addition, the dietary intake is lower on DDs, highlighting the importance of focusing efforts to improve nutritional intake mainly during the day of dialysis treatment.

Making the invisible visible: imaging techniques for assessing muscle mass and muscle quality in chronic kidney disease.

Muscle wasting and low muscle mass are prominent features of protein energy wasting (PEW), sarcopenia and sarcopenic obesity in patients with chronic kidney disease (CKD). In addition, muscle wasting is associated with low muscle strength, impaired muscle function and adverse clinical outcomes such as low quality of life, hospitalizations and increased mortality. While assessment of muscle mass is well justified, the assessment of skeletal muscle should go beyond quantity. Imaging techniques provide the means for non-invasive, comprehensive, in-depth assessment of the quality of the muscle such as the infiltration of ectopic fat. These techniques include computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound. Dual energy X-ray absorptiometry is also an imaging technique, but one that only provides quantitative and not qualitative data on muscle. The main advantage of imaging techniques compared with other methods such as bioelectrical impedance analysis and anthropometry is that they offer higher precision and accuracy. On the other hand, the higher cost for acquiring and maintaining the imaging equipment, especially CT and MRI, makes these less-used options and available mostly for research purposes. In the field of CKD and end-stage kidney disease (ESKD), imaging techniques are gaining attention for evaluating muscle quantity and more recently muscle fat infiltration. This review describes the potential of these techniques in CKD and ESKD settings for muscle assessment beyond that of muscle quantity.

Sarcopenia diagnosed by ultrasound-assessed quadriceps muscle thickness and handgrip strength predicts mortality in patients on hemodialysis.

BACKGROUND: Estimation of muscle mass is a pivotal component in the diagnosis of protein-energy wasting and sarcopenia. While bioimpedance spectroscopy is a widely  accepted technique for the assessment of lean tissue related to the diagnosis of sarcopenia, to date skeletal muscle ultrasound (US) has not gained full acceptance for this purpose. The aim of this study was to assess the predictive value for mortality of the indexed thickness of the quadriceps vastus intermedius, as measured by US, compared to lean tissue index as estimated by bioimpedance spectroscopy, both combined with handgrip strength in a group of patients with end-stage kidney disease (ESKD) on maintenance hemodialysis (HD). METHODS: The cut-off values for low handgrip strength were < 27 kg for males and < 16 kg for females. The cut-off value for low lean tissue index was obtained from an age-matched healthy control group, with low lean tissue index being defined as values below the 10th percentile of the distribution of healthy subjects. The cut-off values for low quadriceps vastus intermedius thickness index were < 3.44 mm/m2 for males and < 3.52 mm/m2 for females. RESULTS: Ultrasound and bioimpedance spectroscopy were performed in 99 patients, and handgrip strength was assessed in 64 patients, all on maintenance HD. After a median follow-up of 28 months (interquartile range 19-41 months) 38 patients died. Lean tissue index was not associated with mortality, while low quadriceps vastus intermedius thickness index and low handgrip strength were associated with an increased hazard of death. In the fully adjusted model, only the combination of low handgrip strength and low quadriceps vastus intermedius thickness index was significantly associated with higher mortality. CONCLUSION: When combined with low handgrip strength, low quadriceps muscle US outperformed low lean tissue index as assessed by bioimpedance spectroscopy in predicting mortality in a cohort of patients on maintenance HD. Ultrasound may be a useful and convenient technique for the assessment of sarcopenia and protein-energy wasting in this patient population.