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.

GLIM in chronic kidney disease: What do we need to know?

The lack of consensus on diagnostic criteria for malnutrition has hampered developments in research and clinical practice pertaining to nutrition. This opinion paper describes the applicability and other aspects of using the Global Leadership Initiative on Malnutrition (GLIM) criteria for diagnosing malnutrition in patients with chronic kidney disease (CKD). We examine the purpose of GLIM, the particularities of CKD that can affect the nutritional and metabolic status and the diagnosis of malnutrition. In addition, we make an appraisal of previous studies that used GLIM in the context of CKD and discuss the value and relevance of using the GLIM criteria in patients with CKD.

Comparison between FRAIL Scale and Clinical Frailty Scale in predicting hospitalization in hemodialysis patients.

BACKGROUND: To assess the prevalence of frailty by the Clinical Frailty Scale (CFS) and the 5-item FRAIL scale and their association with hospitalization in hemodialysis (HD) patients. METHODS: This was a prospective observational study. We included patients of both genders ≥ 18 years old in HD treatment for at least 3 months. Demographic, clinical, and routine laboratory data were retrieved from the medical charts. Two different frailty assessment tools were used, the CFS and the FRAIL scale. Participants were followed up for 9 months and hospitalizations for all causes were evaluated. A Venn diagram was constructed to show the overlap of possible frailty and pre-frailty. Cox regression was used to identify the association between frailty and hospitalization. The significance level was 5%. RESULTS: A total of 137 subjects were included in the analysis. The median age was 61 (52-67) years and 60% were male. The hospitalization rate and mortality in 9 months were 22.6% and 7.29%, respectively. Regarding frailty, the overall prevalence was 13.8% assessed by CFS and 36.5% according to the FRAIL scale. In the Cox regression, frailty by FRAIL scale was associated with a 2.8-fold increase in the risk of hospitalization (OR = 2.880; 95% CI = 1.361-6.096; p = 0.006), but frailty assessed by the CFS was not associated with the need for hospitalization. CONCLUSION: In HD patients, the FRAIL scale proved to be an easy-to-apply tool, identifying a high prevalence of frailty and being a predictor of hospital admission.

Serum myostatin levels are associated with physical function and hospitalization in peritoneal dialysis patients.

BACKGROUND: Myostatin functions as a negative regulator of skeletal muscle growth. The association of myostatin with muscle parameters in dialysis patients is inconsistent, and there are no studies associating myostatin with physical function and outcomes in peritoneal dialysis (PD) patients. Therefore, we assessed the association of serum myostatin with lean mass, physical function, and hospitalization in a prospective cohort of PD patients. METHODS: Lean mass, physical function, and serum myostatin were assessed at baseline. Patients were followed up for at least 24 months and hospitalization was recorded. RESULTS: Serum myostatin levels were positively correlated with handgrip strength and Appendicular Lean Mass Index among male patients. Binary logistic regression models were performed including myostatin levels and physical function parameters as independent variables. Serum myostatin, handgrip strength, gait speed, and Short Physical Performance Battery were associated with hospitalization. CONCLUSION: Lower serum myostatin and physical function were associated with hospitalization in PD patients.

Association between phase angle and coronary artery calcium score in patients on peritoneal dialysis.

Introduction: The phase angle (PhA) has been used as a nutritional marker and predictor of mortality in patients on peritoneal dialysis (PD). The coronary artery calcium (CAC) score has shown to predict the incidence of acute myocardial infarction and death from cardiovascular disease in these patients. However, the association between PhA and CAC score in patients with PD is not well-established, which is the objective of this study. Materials and methods: Cross-sectional study with patients on PD, followed up at a University Hospital, between March 2018 and August 2019. PhA was evaluated by unifrequency bioimpedance (BIA). The CAC score was calculated based on cardiovascular computed tomography, considering positive when greater than or equal to 100 Agatston and negative when less than 100 Agatston. Results: We evaluated 44 patients on dialysis, with a mean age of 56 years and median time on dialysis therapy was 11.7 months. In the statistical analysis, a significant association was only observed between the CAC score and the PhA. Conclusion: The PhA is associated with a positive CAC score in patients with PD, and despite other factors, may be useful as a risk marker for coronary artery disease in this population.

Nutritional Parameters in Early and Late Kidney Transplantation.

BACKGROUND: Kidney transplantation (KT) has the advantage of providing a better quality of life and freedom for the patient. However, nutritional changes can occur, with clinical repercussions. The aim of the study was to compare the nutritional status in the initial and late post-KT period. METHODS: A cross-sectional study was conducted involving 169 outpatients post-KT. Clinical, demographic, biochemical, food intake, handgrip strength (HGS), and anthropometric data were collected from medical records for the first nutritional care after KT. Statistical tests were performed to compare the groups according to the time of KT: early (≤1 year) and late (>1 year). The level of significance adopted was 5%. RESULTS: The median age of the patients was 46 years (range, 38-57), 50.3% were men, and it was observed that 66.9% underwent KT with a deceased donor. There was a higher prevalence of diabetes mellitus (42.6% vs 23.5%; P = .011), and higher body mass index (28.80 ± 7.26 vs 26.51 ± 6.62 kg/m2; P = .046), arm muscle circumference (25.84 ± 4.63 vs 24.09 ± 3.36 cm; P = .019), and HGS (26.97 ± 10.70 vs 20.21 ± 10.83 kg; P = .010) in patients with late KT. Linear regression analysis showed that at each log of time, there was an increase of 1.90 kg in HGS (P = .045) and 0.48 cm (P = .036) in mid-arm muscle circumference. CONCLUSION: The present study demonstrated that late kidney transplantation was associated with higher values of body mass index, mid-arm muscle circumference, and HGS.

Association of Phase Angle, but Not Inflammation and Overhydration, With Physical Function in Peritoneal Dialysis Patients.

Introduction: Muscle mass depletion, overhydration, and inflammatory state have been related to impaired physical function in chronic kidney disease patients. The relationship between bioelectrical impedance analysis (BIA) parameters, such as hydration status and phase angle (PhA), with physical function in peritoneal dialysis (PD), is still not well-established. Therefore, the objective was to evaluate the association of BIA parameters (overhydration index and PhA) and inflammatory markers with physical function in patients on PD. Methods: The present cross-sectional study enrolled PD patients. Multifrequency BIA was performed to obtain overhydration index and PhA. The Short Physical Performance Battery (SPPB) test battery was applied to assess physical function. The time to complete the 4-m gait test and sit-to-stand test was also considered for physical function assessment. The inflammatory markers tumor necrosis factor-alpha and C-reactive protein levels were determined. Multiple linear regression models were performed, with the physical function variables as dependent variables, adjusted for age, diabetes, and sex. Results: Forty-nine PD patients were enrolled, 53.1% (n = 26) women; mean age, 55.5 ± 16.3 years. There were significant correlations between PhA and SPPB (r = 0.550, p < 0.001), time of 4-m gait test (r = -0.613, p < 0.001) and sit-to-stand test and (r = -0.547, p < 0.001). Overhydration index was significantly correlated with SPPB, 4-m gait test (r = 0.339, p = 0.017), and sit-to-stand test (r = 0.335, p = 0.019). Inflammatory markers were not significantly correlated with physical function parameters. In the multiple linear regression analysis, PhA was associated with physical function parameters, even after adjustments. Overhydration index was associated with all physical function tests only in the models with no adjustments. Conclusion: PhA was independently associated with physical function in PD patients. Inflammatory markers and overhydration index were not associated with physical function.

Agreement of Single-Frequency Electrical Bioimpedance in the Evaluation of Fat Free Mass and Fat Mass in Peritoneal Dialysis Patients.

Background: Protein-energy wasting is related to impairment of quality of life and lower survival of end-stage kidney disease (ESKD) patients. The evaluation of body composition, especially fat free mass (FFM) and fat mass (FM), is important for the prediction of outcomes in these individuals. The aim of this study was to compare the FFM and FM measurements obtained by single-frequency bioimpedance (SF-BIA) and by a multiple frequency bioimpedance (MF-BIA) device, using dual energy X-ray absorptiometry (DXA) peritoneal dialysis (PD) patients. Methods: This was a cross-sectional study involving adult patients undergoing regular PD, in which we performed SF-BIA, MF-BIA, and DXA at the same visit. To compare the bioimpedance values with DXA, we used: Person correlation (r), intraclass correlation coefficient (ICC), and Bland-Altman concordance analysis. Results: The sample consisted of 50 patients in the PD, with mean age of 55.1 ± 16.3 years. Both bioimpedance methods showed a strong correlation (r > 0.7) and excellent reproducibility (ICC > 0.75) compared to DXA. According to the Bland-Altman diagram, SF-BIA showed agreement in body compartment measurements, with no proportionality bias (p > 0.05), without systematic bias for FFM (-0.5 ± 4.9, 95% CI -1.8 to 0.9, p = 0.506), and for FM (0.3 ± 4.6, p = 0.543). MF-BIA did not present a proportionality bias for the FFM, but it underestimated this body compartment by 2.5 ± 5.4 kg (p = 0.002). In addition, MF-BIA presented proportionality bias for FM. Conclusion: SF-BIA was a more accurate assessing method than MBIA for FFM and FM measurements in PD patients. Because it is a low-cost, non-evaluator-dependent measurement and has less systematic bias, it can also be recommended for fat mass and free-fat mass evaluation in PD patients.

Age, diabetes mellitus, and dialysis modality are associated with risk of poor muscle strength and physical function in hemodialysis and peritoneal dialysis patients.

BACKGROUND: Due to the poor outcomes associated with the impairment of physical function and muscle strength in patients on maintenance dialysis, it is important to understand the factors that may influence physical function and muscle strength. The aim of this study was to explore the factors associated with physical function in hemodialysis and peritoneal dialysis patients. METHODS: Patients with chronic kidney disease on dialysis for at least 3 months, aged 18 years old or above, were enrolled. Physical function was assessed by handgrip strength, gait and sit-to-stand tests, and the Short Physical Performance Battery (SPPB). Clinical and laboratory data were collected to verify the association with physical function parameters through binary logistic regression. RESULTS: One-hundred ninety patients on maintenance dialysis were included; 140 patients (73.7%) on hemodialysis and 50 (26.3%) on peritoneal dialysis. The mean age was 57.3 ± 14.9 years, 109 (57.4%) were male, and 87 (45.8%) were older than 60 years. The median SPPB was 8.0 points (6.0-10.0 points) and the mean ± standard deviation of handgrip strength was 24.7 ± 12.2 kg. Binary logistic regression showed that age, type of renal replacement therapy, diabetes mellitus, and serum creatinine were significantly associated with both higher 4-meter gait test times and lower SPPB scores. Only age and diabetes mellitus were associated with higher sit-to-stand test times, while age and ferritin were associated with lower handgrip strength. CONCLUSION: Age, diabetes mellitus, serum creatinine, and hemodialysis modality are factors related to physical function in dialysis patients.

Which Method Should Be Used to Assess Protein Intake in Peritoneal Dialysis Patients? Assessment of Agreement Between Protein Equivalent of Total Nitrogen Appearance and 24-Hour Dietary Recall.

OBJECTIVES: After dialysis initiation, a high protein diet is recommended due to significant nutrient losses through dialysate and increased risk of protein energy wasting. In peritoneal dialysis (PD) patients, protein intake can be assessed through different methods that have some advantages and limitations, which affect its use on routine care. The aim of this study is to evaluate the agreement between 2 different methods (24-hour dietary recall and PNA-protein equivalent of total nitrogen appearance) on estimating protein intake in PD patients. DESIGN AND METHODS: Patients on PD for at least 3 months, aged 18 years old or more, were enrolled. To estimate protein intake, 24-hour dietary recall and PNA was used. PNA was calculated from 24-hour urine on the same day of the 24-hour dietary recall. RESULTS: Fifty individuals on PD were included, mean age 55.7 ± 16.2 years, and body mass index 26.0 ± 4.5 kg/m2. The average energy consumption was 1788.79 ± 504.40 kcal/day, which corresponds to 26.81 ± 9.11 kcal/kg current body weight (BW)/day and 29.82 ± 8.39 kcal/kg ideal body weight (IBW)/day. The median of total daily and normalized protein intake estimated using dietary recall was 61.43 (45.28-87.40) g/day, 0.90 (0.58-1.22) g/kg current BW/day, and 1.04 (0.77-1.32) g/kg IBW/day, respectively. Daily protein intake estimated by PNA was 55.75 (48.27-67.74) g/day, protein intake normalized by current BW was 0.81 (0.72-0.99) g/kg and 0.92 (0.83-1.06) g/kg IBW/day. Bland-Altman analysis indicates no systematic bias for the assessment of total protein intake and normalized protein intake for current and ideal BW. Significant proportionality bias was observed for both evaluations, showing there is a dispersion of the values. CONCLUSIONS: Despite the absence of systematic bias in the Bland-Altman analysis, there is no agreement in the assessment of protein intake by dietary recall and PNA, due to the existence of proportionality bias. Thus, values can be influenced biased by the magnitude of the measures.

Correction: Update of the European consensus on sarcopenia: what has changed in diagnosis and prevalence in peritoneal dialysis?

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Update of the European consensus on sarcopenia: what has changed in diagnosis and prevalence in peritoneal dialysis?

Patients on peritoneal dialysis (PD) may be affected by sarcopenia, which is a progressive and generalized skeletal muscle disorder characterized by muscle mass atrophy with decline of muscle strength and function. The aim was to evaluate differences in the diagnosis and prevalence of sarcopenia according to European Working Group on Sarcopenia in Older People (EWGSOP). The screening for sarcopenia was performed in PD patients older than 18 years, with evaluation of appendicular skeletal muscle mass index (ASMMI), handgrip strength (HGS) and gait speed (GS). The diagnosis was according to the 2010 and 2019 versions of EWGSOP consensus on sarcopenia. Fifty subjects on PD were included, mean age 55.74 ± 16.22 years old, 52% female. The prevalence of sarcopenia ranged from 4 to 10% according to cut points and references used.