Predictors of protein-energy wasting in haemodialysis patients: a cross-sectional study

Associations between bioelectrical impedance analysis-derived phase angle, protein-energy wasting and all-cause mortality in older patients undergoing haemodialysis

AIM

Protein-energy wasting (PEW) is a common syndrome in patients undergoing haemodialysis (HD) and is associated with poor prognosis. Bioelectrical impedance analysis (BIA)-derived phase angle (PA) is useful for predicting PEW, but sex and age need to be considered. We aimed to reveal sex-specific cut-off values of PA predicting PEW in HD patients aged ≥65.

METHODS

This two-centre retrospective cohort study included patients on HD who underwent BIA. PEW was detected using the International Society of Renal Nutrition and Metabolism (ISRNM) criteria as a reference. The PA was measured using a multifrequency bioimpedance device. Sex-specific cut-off values of PA predicting PEW were detected by receiver-operator characteristic analysis. We investigated the association between PEW determined using sex-specific cut-off values for PA and all-cause mortality.

RESULTS

This study included 274 patients undergoing HD, with a median age of 75 (70-80) years, mean PA of 3.8 ± 1.1° and PEW of 43%. Over a median follow-up duration of 1095 (400-1095) days, 111 patients died. Cut-off values of PA predicting PEW were as follows: female, 3.00° (sensitivity, 87.3%; specificity, 77.5%), and male, 3.84° (sensitivity, 77.6%; specificity, 71.4%). The kappa coefficient between sex-specific cut-off values of the PA and ISRNM criteria had a moderate coincidence level of 0.55. PEW detected by PA was independently associated with all-cause mortality (hazard ratio: 2.40; 95% confidence interval: 1.51-3.85; p < .001).

CONCLUSIONS

Sex-specific cut-off values for PA in older HD patients may be useful as a screening tool for predicting PEW and mortality.

Clinical Significance of Nutritional Status, Inflammation, and Body Composition in Elderly Hemodialysis Patients-A Case-Control Study

Nutritional and inflammatory disorders are factors that increase the risk of adverse clinical outcomes and mortality in elderly hemodialysis (HD) patients. This study aimed to examine nutritional and inflammation status as well as body composition in older adults on HD compared to matched controls. A case-control study was conducted on 168 older participants (84 HD patients (cases) and 84 controls) age- and sex-matched. Demographic, clinical, anthropometric, and laboratory parameters were collected from medical records. The primary outcome was nutritional status assessment using a combination of nutritional and inflammatory markers along with the geriatric nutritional risk index (GNRI). Sarcopenic obesity (SO) was studied by the combined application of anthropometric measures. Body composition and hydration status were assessed by bioelectrical impedance analysis (BIA). Univariate and multivariate regression analyses were performed to identify nutritional and inflammatory independent risk indicators in elderly HD patients and controls. A significantly high prevalence of nutritional risk measured by the GNRI was found in HD patients (32.1%) compared to controls (6.0%) (p < 0.001). Elderly HD patients were overweight and had lower percent arm muscle circumference, phase angle (PA), serum albumin (s-albumin), as well as higher percent extracellular body water (ECW%) and serum C-reactive protein (s-CRP) than controls (all at least, p < 0.01). SO was higher in HD patients (15.50%) than in controls (14.30%). By multi-regression analyses, age < 75 years (OR: 0.119; 95%CI: 0.036 to 0.388), ECW% (OR: 1.162; 95%CI: 1.061 to 1.273), PA (OR: 0.099; 95%CI: 0.036 to 0.271), as well as BMI, s-albumin ≥ 3.8 g/dL, and lower s-CRP were independently related between cases and controls (all at least, p < 0.05). Elderly HD patients had increased nutritional risk, SO, inflammation, overhydration, and metabolic derangements compared to controls. This study highlights the importance of identifying nutritional risk along with inflammation profile and associated body composition disorders in the nutritional care of elderly HD patients. Further studies are needed to prevent nutritional disorders in elderly HD patients.

Study on the correlation between bioelectrical impedance analysis index and protein energy consumption in maintenance dialysis patients

BACKGROUND

Protein-energy wasting (PEW) has been reported to be pretty common in maintenance dialysis patients. However, the existing PEW diagnostic standard is limited in clinical use due to the complexity of it. Bioelectrical impedance analysis (BIA), as a non-invasive nutritional assessment method, can objectively and quantitatively analyze the changes of body tissue components under different nutritional states. We aim to explore the association between PEW and BIA and establish a reliable diagnostic model of PEW.

METHODS

We collected cross-sectional data of 609 maintenance dialysis patients at the First Affiliated Hospital, College of Medicine, Zhejiang University. PEW was diagnosed according to International Society of Renal Nutrition and Metabolism (ISRNM) criteria. Among them, 448 consecutive patients were included in the training set for the establishment of a diagnostic nomogram. 161 consecutive patients were included for internal validation. 52 patients from Zhejiang Hospital were included for external validation of the diagnostic model. Correlation analysis of BIA indexes with other nutritional indicators was performed. Logistic regression was used to examine the association of BIA indexes with PEW. 12 diagnostic models of PEW in maintenance dialysis patients were developed and the performance of them in terms of discrimination and calibration was evaluated using C statistics and Hosmer-Lemeshow-type χ2 statistics. After comparing to existing diagnostic models, and performing both internal and external validation, we finally established a simple but reliable PEW diagnostic model which may have great value of clinical application.

RESULTS

A total of 609 individuals from First Affiliated Hospital, College of Medicine, Zhejiang University and 52 individuals from Zhejiang Hospital were included. After full adjustment, age, peritoneal dialysis (compared to hemodialysis), subjective global assessment (SGA, compared to non-SGA) and water ratio were independent risk factors, while triglyceride, urea nitrogen, calcium, ferritin, BCM, VFA and phase angle were independent protective factors of PEW. The model incorporated water ratio, VFA, BCM, phase angle and cholesterol revealed best performance. A nomogram was developed according to the results of model performance. The model achieved high C-indexes of 0.843 in the training set, 0.841 and 0.829 in the internal and external validation sets, respectively, and had a well-fitted calibration curve. The net reclassification improvement (NRI) showed 8%, 13%, 2%, 38%, 36% improvement of diagnostic accuracy of our model compared with "PEW score model", "modified PEW score model", "3-index model", "SGA model" and "BIA decision tree model", respectively.

CONCLUSIONS

BIA can be used as an auxiliary tool to evaluate PEW risk and may have certain clinical application value.

Interaction Effect of Phase Angle and Age on Femoral Neck Bone Mineral Density in Patients with Non-Dialysis Chronic Kidney Disease Stage 5

Background: Low bone mass is common in malnourished patients with chronic kidney disease (CKD) and can lead to a higher risk of fractures. Elderly and CKD patients have the same risk factors for protein-energy wasting, sarcopenia, and osteoporosis. Here, we investigated the association between phase angle (PhA) and bone mineral density (BMD) in dialysis-naïve patients with CKD stage 5 (CKD5) and identified a statistical relationship between PhA and age, which affects bone density. Methods: Bio-impedance spectroscopy for evaluating body composition and PhA and dual-energy X-ray absorptiometry for determining the BMD were simultaneously performed in 167 consecutive patients (mean age, 59.65 ± 13.98 years; women, 40.1%). Two-way analysis of variance (ANOVA) was conducted to assess the potential interaction effect of PhA and age on femoral neck BMD (FN-BMD). Results: Our results showed that PhA and age were independently associated with FN-BMD and T-score in multiple linear regressions analyses. A significant interaction effect of PhA and age on FN-BMD was found on two-way ANOVA (p = 0.028). The average BMD values for the first and second tertiles of the PhA were higher in the young versus elderly group, whereas patients in the elderly group had higher BMD in the third tertiles. Conclusions: A relationship was noted between PhA and BMD in patients with advanced-stage CKD. The effect of PhA level on FN-BMD differed between elderly and young patients. Our study suggested that higher PhA levels could be a marker explaining the maintenance of good bone health in elderly patients with CKD5. Further longitudinal analyses are needed to determine whether PhA predicts the risk of CKD-MBD-related fractures during CKD progression.

Utility of the Global Leadership Initiative on Malnutrition criteria for the nutritional assessment of patients with end-stage renal disease receiving chronic hemodialysis

BACKGROUND

Malnutrition is associated with adverse outcomes in patients on chronic haemodialysis. Thus, identifying accurate methods for diagnosing malnutrition is essential. The present retrospective study investigated the utility of the new Global Leadership Initiative on Malnutrition (GLIM) criteria in patients undergoing chronic haemodialysis.

METHODS

Phase angle and fat-free mass index (FFMI) were derived using bioelectrical impedance analysis. Malnutrition was determined when the subjects had at least one phenotypic criterion (weight loss, low body mass index [BMI] or FFMI).

RESULTS

This study included 103 patients undergoing chronic haemodialysis and 46 (44.7%) patients were diagnosed as malnourished. Malnutrition determined using the GLIM criteria was associated with increased risks of all-cause death (hazard ratio = 3.0, p = 0.044) and infection requiring hospitalisation (hazard ratio = 2.4, p = 0.015), independent of age, sex and comorbidities. However, malnutrition was not related to major adverse cardiovascular events (p = 0.908). We further evaluated the longitudinal changes in phenotypic parameters. Subjects with median levels of high-sensitivity C-reactive protein exceeding 5 mg L^-1 exhibited decreased body weight and BMI (p = 0.015 and 0.016, respectively). In addition, body weight, BMI and FFMI were reduced in subjects with a median protein catabolic rate of < 1.0 mg kg^-1 day^-1 , even after adjustment for age, sex and comorbidities (p = 0.026, 0.053 and 0.039, respectively).

CONCLUSIONS

Malnutrition assessed using the GLIM criteria could be a useful predictor of mortality and infection in patients on chronic haemodialysis. To improve nutritional status, approaches for decreasing inflammation and increasing protein intake are needed.

Nutritional Predictors of Mortality after 10 Years of Follow-Up in Patients with Chronic Kidney Disease at a Multidisciplinary Unit of Advanced Chronic Kidney Disease

Nutritional monitoring in advanced chronic kidney disease (ACKD) units provides personalized care and improves clinical outcomes. This study aimed to identify mortality risk factors in chronic kidney disease (CKD) patients on nutritional follow-up in the multidisciplinary ACKD unit. A retrospective cross-sectional observational study was conducted in 307 CKD patients’ stage 3b, 4−5 followed-up for 10 years. Clinical and nutritional monitoring was performed by malnutrition-inflammation score (MIS), biochemical parameters (s-albumin, s-prealbumin, and serum C-reactive protein (s-CRP), body composition measured by bioelectrical impedance analysis (BIA), anthropometry, and handgrip strength measurements. The sample was classified into non-survivors, survivors, and censored groups. Of the 307 CKD patients, the prevalence of protein-energy wasting (PEW) was 27.0% using MIS > 5 points, s-CRP > 1 mg/dL was 19.20%, and 27.18% died. Survivors had higher significant body cell mass (BCM%) and phase angle (PA). Survival analyses significantly showed that age > 72 years, MIS > 5 points, s-prealbumin ≤ 30 mg/dL, PA ≤ 4°, and gender-adjusted handgrip strength (HGS) were associated with an increased risk of mortality. By univariate and multivariate Cox regression, time on follow-up (HR:0.97), s-prealbumin (HR:0.94), and right handgrip strength (HR:0.96) were independent predictors of mortality risk at 10 years of follow-up in the ACKD unit. Nutritional monitoring in patients with stage 3b, 4−5 CKD helps to identify and treat nutritional risk early and improve adverse mortality prognosis.

Nutritional Status, Body Composition, and Inflammation Profile in Older Patients with Advanced Chronic Kidney Disease Stage 4-5: A Case-Control Study

Nutritional status is a predictor of adverse outcomes and mortality in patients with advanced chronic kidney disease (ACKD). This study aimed to explore and evaluate risk factors related to nutritional status, body composition, and inflammatory profile in patients with ACKD compared with age- and sex-matched controls in a Mediterranean cohort of the Spanish population. Out of 200 volunteers recruited, 150 participants (64%) were included, and a case-control study was conducted on 75 ACKD patients (stages 4−5), matched individually with controls at a ratio of 1:1 for both age and sex. At enrolment, demographic, clinical, anthropometric, and laboratory parameters were measured. Bioimpedance analysis (BIA) was used to assess both body composition and hydration status. ACKD patients had lower body cell mass (BCM%), muscle mass (MM%) phase angle (PA), s-albumin, and higher C-reactive protein (s-CRP) than controls (at least, p < 0.05). PA correlated positively with BCM% (cases: r = 0.84; controls: r = 0.53, p < 0.001), MM% (cases: r = 0.65; controls: r = 0.31, p < 0.001), and inversely with s-CRP (cases: r = −0.30, p < 0.001; controls: r = −0.31, p = 0.40). By univariate and multivariate conditional regression analysis, total body water (OR: 1.186), extracellular mass (OR: 1.346), s-CRP (OR: 2.050), MM% (OR: 0.847), PA (OR: 0.058), and s-albumin (OR: 0.475) were significantly associated among cases to controls. Nutritional parameters and BIA-derived measures appear as prognostic entities in patients with stage 4−5 ACKD compared to matched controls in this Mediterranean cohort.

The Relation of Serum Dehydroepiandrosterone Sulfate Level to Protein Energy Wasting in Hemodialysis Patients

Protein-energy wasting (PEW) is a major risk for morbidity and mortality in hemodialysis (HD) patients. The change in the concentration of dehydroepiandrosterone sulfate (DHEA-S) may play a role in PEW. The aim of this work was to study the possible relationship between serum DHEA-S levels and various nutritional and inflammatory parameters in a cohort of HD patients. In total, 78 HD patients (47 males and 31 females) were included in this crosssectional observational study. In addition to taking their history, clinical examinations, and routine laboratory investigations, the nutritional status was assessed, and their serum DHEA-S was measured. Nutritional status was assessed by anthropometric measures, bioelectrical impedance analysis, malnutrition inflammation scores, and subjective global assessments. A diagnosis of malnutrition was made based on the recommendations of the International Society of Renal Nutrition and Metabolism. The relationship between DHEA-S and various nutritional parameters was analyzed. Eighteen patients (23.1%) suffered from PEW. Those with PEW had a longer duration of HD (P = 0.04), and lower serum levels of creatinine (P = 0.003), hemoglobin (P = 0.01), albumin (P <0.0001), cholesterol (P = 0.02), and DHEA-S (P = 0.01). Among the variables, serum DHEA-S levels were significant predictors of PEW in this cohort (odds ratio: 0.976; 95% confidence interval: 0.954-1.0; P = 0.04). PEW is frequently encountered in HD patients. Decreased serum DHEA-S levels were associated with PEW in male HD patients. Further studies are needed to assess the effect of hormone supplementation on this serious disorder in HD patients.

Association between inflammatory potential of diet and markers of malnutrition in haemodialysis patients

In this study, we aimed to examine the relationship between energy-adjusted dietary inflammatory index (E-DII) and a comprehensive profile of malnutrition in Iranian haemodialysis (HD) patients. In this cross-sectional study, 291 participants on HD for at least 6 months before enrollment were included. The current dietary intakes of participants were assessed using a 4-d diet diary-assisted recall, including 2 non-dialysis days and 2 dialysis days to calculate E-DII. To determine the malnutrition status of HD patients, BMI, subjective global assessment (SGA), dialysis malnutrition score (DMS) and malnutrition inflammation score (MIS) were used. Overall, 291 HD patients comprised our study population. After controlling for potential confounders, E-DII was associated with a higher risk of malnutrition, as evidenced by SGA (OR = 2·23; 95 % CI: 1·11, 4·49), DMS (OR = 2·31; 95 % CI: 1·16, 4·60) and MIS (OR = 2·50; 95 % CI: 1·28, 4·88). No significant association was detected between E-DII and BMI either before (OR = 1·78; 95 % CI: 0·83, 3·81) or after adjustment for possible confounders (OR = 1·43; 95 % CI: 0·58, 3·54). This study showed that E-DII was significantly associated with reliable malnutrition markers including SGA, DMS and MIS in HD patients. However, further longitudinal studies are warranted to infer a cause-and-effect relationship between DII and malnutrition.

Impact of phase angle and sarcopenia estimated by bioimpedance analysis on clinical prognosis in patients undergoing hemodialysis: A retrospective study

Bioimpedance analysis (BIA) has been widely used in the evaluation of body composition in patients undergoing maintenance hemodialysis. We conducted this study to evaluate impact of phase angle (PA) and sarcopenia measured by BIA on clinical prognosis in these patients.This longitudinal retrospective study enrolled patients who underwent hemodialysis between January 2016 and March 2019. The patients were stratified into higher (> 4°) and lower (≤ 4.0°) PA groups. Sarcopenia was defined when the appendicular skeletal muscle mass was < 20 kg in men and < 15 kg in women.Of the 191 patients, 63.4% were men. The mean age was 64.2 ± 12.4 years. The lower PA group was older, had a higher proportion of women, a lower body mass index, lower albumin, cholesterol, uric acid, and phosphorus levels, and a higher incidence of history of coronary artery disease than the higher PA group. Linear regression analysis revealed that PA was significantly associated with body mass index (B = 0.18, P = .005), serum albumin (B = 0.23, P = .001), and creatinine levels (B = 0.32, P < .001). During a median follow-up of 16.7 months, 14.1% (n = 27) of patients experienced major adverse cardiovascular events and 11.0% (n = 21) died. Kaplan-Meier survival analysis showed that the higher PA group had significantly better survival, regardless of sarcopenia. Multivariate Cox analyses revealed that lower PA (0.51 [0.31-0.85], P = .010), higher IDWG (1.06 [1.01-1.12], P = .028) and C-reactive protein level (1.01 [1.01-1.02], P < .001), and a history of coronary artery disease (3.02 [1.04-8.77], P = .042) were significantly related to all-cause mortality after adjusting for other covariates.PA measured by BIA was an independent factor in the prediction of mortality in maintenance hemodialysis patients, regardless of sarcopenia. Intervention studies are needed to confirm if the improvement in PA is associated with better clinical outcome.

The Extracellular Mass to Body Cell Mass Ratio as a Predictor of Mortality Risk in Hemodialysis Patients

The extracellular mass/body cell mass ratio (ECM/BCM ratio) is a novel indicator of nutritional and hydration status in hemodialysis (HD) patients. This study aimed to explore the ECM/BCM ratio as a predictor of mortality risk with nutritional-inflammatory markers in HD patients. A prospective observational study was conducted in 90 HD patients (male: 52.2%; DM: 25.60%). Clinical and biochemical parameters [serum albumin, serum C-reactive protein (s-CRP), interleukine-6 (IL-6)] were analysed and bioelectrical impedance analysis (BIA) was performed. Protein-energy wasting syndrome (PEW) was diagnosed using malnutrition-inflammation score (MIS). Based on BIA-derived measurements, the ECM/BCM ratio with a cut-off point of 1.20 was used as a PEW-fluid overload indicator. Comorbidity by Charlson index and hospital admissions were measured. Out of 90 HD patients followed up for 36 months, 20 patients (22.22%) died. PEW was observed in 24 survivors (34.28%) and all non-survivors. The ECM/BCM ratio was directly correlated with MIS, s-CRP, Charlson index and hospital admissions but was negatively correlated with phase angle and s-albumin (all, p < 0.001). Values of the ECM/BCM ratio ≥ 1.20 were associated with higher probability of all-cause mortality (p = 0.002). The ECM/BCM ratio ≥ 1.20, IL-6 ≥ 3.1 pg/mL, s-CRP and s-albumin ≥ 3.8 g/dL and Charlson index were significantly associated with all-cause mortality risk in multivariate adjusted analysis. This study demonstrates that the ECM/BCM ratio ≥ 1.20 as a nutritional marker and/or fluid overload indicator had a significant prognostic value of death risk in HD patients.

Mouse Model of Critical Persistent Inflammation, Immunosuppression, and Catabolism Syndrome

ABSTRACT

Persistent inflammation, immunosuppression, and catabolism syndrome (PIICS) is a growing challenge in intensive care units (ICUs). PIICS causes a severe illness with high mortality. Currently, treatment is expensive, and the outcomes are dismal. Herein, we established a PIICS model to study the disease pathophysiology and its potential treatment. Using a modified sublethal cecal ligation and puncture (CLP) to induce sepsis (day 1) and the injection of lipopolysaccharide (LPS) to induce an aggravated inflammation response (day 11), CLP + LPS mice recapitulating PIICS features were successfully generated (day 14). Adult male mice were divided into CLP + LPS, CLP + daily chronic stress (DCS), CLP, DCS, LPS, and sham control groups. A survival curve was generated, and phenotypes were analyzed using markers for catabolism, inflammation, and immunosuppression. The CLP + LPS model showed two mortality peaks (after CLP and after LPS), whereas the CLP + DCS and CLP groups showed one peak. Surviving CLP + LPS mice exhibited significantly increased catabolism and inflammatory cytokine levels and aggravated inflammation, including organ inflammation. CLP + LPS mice exhibited strong immune suppression as evidenced by decreased splenic cluster of differentiation (CD)8+ and interferon-γ+CD8+ T cell counts and a concomitant and significant increase in the myeloid-derived suppressor cell population. This CLP+LPS-induced PIICS model differs from acute sepsis models, showing two mortality peaks and a protracted course of 14 days. Compared to previous PIICS models, ours shows a re-aggravated status and higher catabolism, inflammation, and immunosuppression levels. Our aim was to use the PIICS model to simulate PIICS pathophysiology and course in the ICU, enabling investigation of its mechanism and treatment.

Validation of the functional assessment of anorexia/cachexia therapy instrument to assess quality of life in maintenance hemodialysis patients with cachexia

BACKGROUND

Many patients on maintenance hemodialysis (MHD) eventually suffer from cachexia. The Functional Assessment of Anorexia/Cachexia Therapy (FAACT) is a tool used to evaluate the quality of life of patients with cachexia related to various diseases, but its suitability for use in MHD patients has yet to be verified. This study aimed to explore the validation of the FAACT in MHD patients by conducting reliability and validity tests.

METHODS

Qualified MHD patients were selected to complete the FAACT and Kidney Disease Quality of Life Short Form 36 (KDQOL-36) questionnaires, and their demographic data and biochemical test results were collected from electronic medical records. Next, the Cronbach's alpha coefficient, paired sample t test and ICC were used to analyze the scale consistency. Additionally, the association between the KDQOL-36 and FAACT was analyzed using Bland-Altman plots and Pearson correlation analysis. Finally, the patients were divided into groups to evaluate discriminant validity.

RESULTS

A total of 299 patients were included in this study. The Cronbach's alpha coefficients of the FAACT and its anorexia-cachexia subscale (ACS) were 0.904 and 0.842, respectively, and their ICC exceeded 0.90. The correlation coefficients between the FAACT and its items ranged from 0.146 to 0.631, and the correlation coefficients between the FAACT and KDQOL-36 dimensions ranged from 0.446 to 0.617. The Bland-Altman plots between the FAACT and KDQOL-36 showed that only 3.3% of the points were outside the 95% limits of agreement. The effects of cachexia status (present or absent) on FAACT and ACS scores had effect sizes of 0.54 (P < 0.001) and 0.60 (P < 0.001), respectively. The FAACT and ACS also significantly discriminated between patients with and without inflammation (P < 0.001).

CONCLUSIONS

The FAACT and ACS have acceptable reliability and validity in MHD patients and are suitable for measuring the quality of life of MHD patients with cachexia.

Bioelectrical Impedance Analysis Derived-Phase Angle as a Pragmatic Tool to Detect Protein Energy Wasting among Multi-Ethnic Hemodialysis Patients

Protein-energy wasting (PEW) is a devastating metabolic derangement that leads to increased morbidity and mortality in hemodialysis (HD) patients. This study aimed to determine the diagnostic test accuracy of bioelectrical impedance analysis derived-phase angle (PhA) in detecting PEW among HD patients. This was a multi-centre, cross-sectional study conducted amongst 152 multi-ethnic HD patients in Klang Valley, Malaysia. PEW was assessed using the International Society of Renal Nutrition and Metabolism criteria as the reference method. PhA was measured using a multi-frequency bioelectrical impedance spectroscopy at 50 kHz. Multiple and logistic regressions were used to determine factors associated with PhA and PEW diagnosis, respectively. A receiver operating characteristics curve analysis was used to establish the gender-specific PhA cut-offs to detect PEW. PEW existed in 21.1% of the HD patients. PhA was found as an independent predictor of PEW (adjOR = 0.308, p = 0.001), with acceptable to excellent discriminative performance (adjAUC_male = 0.809; adjAUC_female = 0.719). Male patients had higher PhA cut-off compared to female patients (4.26° vs. 3.30°). We concluded that PhA is a valid and pragmatic biomarker to detect PEW in multi-ethnic Malaysian HD patients and a gender-specific cut-off is necessary, attributed to the gender differences in body composition.

Bioelectrical impedance analysis-derived phase angle as a determinant of protein-energy wasting and frailty in maintenance hemodialysis patients: retrospective cohort study

Background

Phase angle (PA), measured by bioelectrical impedance analysis (BIA) has been studied as indicator of nutritional status or muscle function in hemodialysis (HD) patients. It remains unclear if the phase angle is associated protein-energy wasting (PEW) or frailty, which are common complication in hemodialysis patients. The aim of this study is to determine whether BIA-derived PA is a marker of PEW or frailty in HD patients.

Methods

This retrospective observational study included 116 adult HD patients (35% female, 64 ± 12 years of age) in a single dialysis center. Patients were classified according to the PA quartiles into four groups; 1) first quartile: PA < 3.7°, 2) second quartile: PA 3.7–4.1°, 3) third quartile: PA 4.2–4.9°and 4) forth quartile: PA ≥ 5.0°. International Society of Renal Nutrition and Metabolism (ISRNM) criteria and Japanese version of Cardiovascular Health Study (J-CHS) criteria were used to identify PEW and frailty.

Results

The lower PA group was associated with a greater risk of PEW (35% vs. 24% vs. 21% vs. 3%; p = 0.032), frailty (59% vs. 40% vs. 21% vs. 3%; p < 0.001). In multivariate logistic regression analysis, the first quartile group was at a significantly greater risk of both PEW and frailty compared with the fourth quartile group after adjusting for other confounding factors.

Conclusions

Lower PA was associated with a greater risk of PEW and frailty in HD patients.

Association between Serum Uric Acid Levels, Nutritional and Antioxidant Status in Patients on Hemodialysis

Purpose: To determine the relationship between uric acid (UA) and nutritional and antioxidant status in hemodialysis (HD) patients, given that hyperuricemia could be an indicator of good nutritional status possibly because of the antioxidant properties of UA. Methods: Cross-sectional study with 93 patients on HD. Hyperuricemia was considered as UA ≥6.0 mg/dL in females and ≥7.0 mg/dL in males. Nutritional variables were registered. Blood samples were taken before the dialysis session to determine oxidative damage as plasma malondialdehyde (MDA) content, and antioxidant capacity measuring 2,2-diphenyl-piclrylhidrazil radical (DPPH^●) scavenging activity and oxygen radical absorbance capacity (ORAC) value. Results: Patients with hyperuricemia had higher creatinine (11.9 vs. 10.5 mg/dL; p = 0.004), potassium (5.5 vs. 5.0 mg/dL; p = 0.014) levels; phase angle (5.8 vs. 4.9; p = 0.005), protein consumption (normalized protein nitrogen appearance, nPNA, 1.03 vs. 0.83; p = 0.013) than normouricemic patients. DPPH^● scavenging activity was higher in hyperuricemic subjects (1.139 vs. 1.049 mM Trolox equivalents; p = 0.007); likewise, hyperuricemic subjects had less oxidant damage measured by MDA (10.6 vs. 12.7 nmol/mL; p = 0.020). Subjects with normouricemia were at higher risk of having a reactance to height (Xc/H) ratio less than 35 (OR 2.79; 95% CI, 1.1–7.017, p = 0.028); nPNA < 1.0 (OR 3.78; 95% CI, 1.4–10.2, p = 0.007), diagnosis of cachexia (OR 2.95; 95% CI, 1156–7.518, p = 0.021), potassium levels <5 (OR 2.97; 95% CI, 1.136–7.772, p = 0.023) and PA < 5.5° (OR 3.38; 95% CI, 1.309–8.749, p = 0.012.) Conclusions: Patients with hyperuricemia had higher antioxidant capacity and better nutritional status. Purines and protein restrictions in HD patients with hyperuricemia need to be reviewed individually for each patient. More studies are needed to stablish a cut point of UA levels in renal population.

Application of blood pre-albumin and NT-pro BNP levels in evaluating prognosis of elderly chronic heart failure patients

Levels of blood pre-albumin (PA) and N-terminal pro-B-type natriuretic peptide (NT-pro BNP) in elderly patients with chronic heart failure (CHF) and their clinical value in prognosis evaluation were explored. A total of 410 elderly patients aged ≥65 years hospitalized for CHF were enrolled. The concentrations of blood PA and NT-pro BNP, routine blood test and biochemistry indicators were determined and color Doppler echocardiography was performed. Additionally, the patients were followed up after discharge, and based on the occurrence of major adverse cardiac events (MACE), they were divided into MACE group and non-MACE group. MACE group had an older age and a higher level of plasma NT-pro BNP than non-MACE group (77.82±6.57) years vs. (76.39±6.18) years, and (8,864.52±9,718.36) pg/ml vs. (4,165.62+6,437.28) pg/ml (P<0.05), and the left ventricular ejection fraction and serum PA level in MACE group were lower than those in non-MACE group (P<0.05). According to the results of multivariate regression analysis, serum PA [odds ratio (OR)=0.242, 95% confidence interval (CI)=0.137-0.406, P<0.001] and plasma NT-pro BNP (OR=1.847, 95% CI=1.024-3.158, P=0.036) were independent risk factors for the occurrence of cardiac events during follow-up. Decline in PA level and elevation in NT-pro BNP level have a strong correlation with poor prognosis of elderly CHF patients, and they can be used for clinically evaluating disease conditions, guiding treatment and improving prognosis.

Potential Role of Nutrient Intake and Malnutrition as Predictors of Uremic Oxidative Toxicity in Patients with End-Stage Renal Disease

Oxidative stress is an important risk factor for cardiovascular disease and death in hemodialysis (HD) patients. However, whether biochemical and nutritional markers might be useful to stratify HD patients according to the risk of oxidative damage remains unclear. We investigated whether low-cost and easily available parameters such as the profile of nutrients intake, nutritional status, and antioxidant defenses can predict lipid and protein oxidation in HD patients. Forty-nine HD patients (women = 20, men = 29), ranging from 18 to 65 years of age (73.5%) were submitted to biochemical and nutritional analysis. At least 93.9% of HD patients had malnutrition. A patient's stratification according to nutritional risk was highly coherent with anthropometric parameters and nutrients intake, which were complementarily used as markers of malnutrition. Nutritional stratification was unable to reveal differences in the oxidative status. On the other hand, carbohydrate and zinc intake, serum zinc (Zn), glutathione peroxidase (GPx) activity, total antioxidant capacity (TAC), and nonprotein antioxidants (npAC) in serum were predictive markers of lipid (R ² = 0.588, P < 0.001) and protein (R ² = 0.581, P < 0.001) oxidation. Interestingly, GPx activity, TAC, and npAC exhibited good (>80% < 90%) or excellent (>90%) accuracy to estimate lipid oxidation (P ≤ 0.01). Regarding the prediction of protein oxidation, GPx activity and TAC presented regular accuracy (>70% < 80%), and Zn serum levels exhibited good sensitivity (P ≤ 0.01). Herein, we provided evidence that clinical characteristics relevant to predict different levels of lipid and protein oxidation in HD patients can be easily obtained, during routine hospital visits by means of the combined analyses of biochemical and nutritional parameters.

Factors related to malnutrition in community-dwelling patients with schizophrenia

PURPOSE

This study aims to identify demographic, clinical, and nutritional factors related to malnutrition in community-dwelling patients with schizophrenia.

DESIGN AND METHODS

We used a descriptive cross-sectional design. Between June and July 2016, 188 community-dwelling patients with schizophrenia were included in this study.

FINDINGS

Of the 188 participants, 4.3% were classified as malnourished, and 40.4% were at risk of malnutrition. Living status, body weight, and appetite were significant factors related to malnutrition in community-dwelling patients with schizophrenia.

PRACTICE IMPLICATION

Assessment of nutritional status should be considered along with demographic and nutritional factors in community-dwelling patients with schizophrenia.

Association of serum IL-18 with protein-energy wasting in end-stage renal disease patients on haemodialysis

PURPOSE

Protein-energy wasting (PEW) is highly prevalent in end-stage renal disease (ESRD) patients with inflammation who are on haemodialysis treatment. Interleukin-18 (IL-18) is an important pro-inflammatory cytokine that is significantly elevated in ESRD patients. However, the relationship between PEW and IL-18 is unclear. We therefore performed a cross-sectional study on 100 ESRD patients undergoing haemodialysis to clarify this.

METHODS

PEW was defined according to the diagnostic criteria of the International Society of Renal Nutrition and Metabolism. Inflammation was assessed based on the serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α) and IL-18. We analysed the association between PEW and IL-18 by using logistic analysis and linear regression after adjustment for basic characteristics, comorbidities and laboratory findings.

RESULTS

Among the 100 haemodialysis patients who were recruited, 56 had PEW. Even though there was no difference between the PEW group and non-PEW group with regard to disease causes, age, gender, cholesterol, ferritin, and haemoglobin, the levels of inflammation indicators such as CRP, IL-6, TNF-α and IL-1β were significantly higher in the PEW group. Moreover, IL-18 was found to contribute to PEW, but was negatively correlated with pre-albumin after adjustment for possible confounding factors.

CONCLUSIONS

Thus, the findings indicate that IL-18 is associated with PEW in ESRD patients on haemodialysis, which suggests that IL-18 may be involved in the pathogenesis of PEW in this setting.

Extracellular mass to body cell mass ratio as a potential index of wasting and fluid overload in hemodialysis patients. A case-control study

BACKGROUND & AIMS

Extracellular mass-to-body cell mass ratio (ECM/BCM ratio) which differentiates the proportion between intraextracellular compartments, could be a nutrition index of being wasted overloaded in hemodialysis (HD) patients. This study aimed to describe a cut-off point of the ECM/BCM ratio and, to find out the relationship between the nutritional-hydration status and this ratio in HD patients.

METHODS

A case-control study was carried out in 64 HD patients individually age-gender-matched to controls. Demographic, clinical and laboratory parameters were recorded. Bioelectrical impedance analysis was used to estimate ECM/BCM ratio as an indicator of the nutritional hydration status. Receiver operator characteristic (ROC) curve analysis was applied to determine the optimal cut-off point for identification of ECM/BCM ratio. An univariate and multivariate conditional logistic regression for the ECM/BCM ratio ≥1.20 was performed.

RESULTS

Median of ECM/BCM ratio was 1.50 (IQR:0.66) in HD patients, whereas 0.87 (IQR: 0.35) was found in controls (p < 0.001). HD-patients had lower body weight, serum albumin (s-albumin) and higher serum C-reactive protein (s-CRP) than controls. By ROC curve analysis, a cut-off point of 1.20 for the ECM/BCM ratio best discriminates to be wasted-overhydrated (sensitivity: 81.2%; specificity: 87.5%). Conditional logistic regression showed that for each 10%, ECM/BCM ratio increase the probability of developing fluid overload was increased 63% (OR: 1.63; 95% CI, 1.15-2.29), whereas an inverse association with s-albumin (OR: 0.15; 95% CI, 0.03-0.61) and other nutritional indicators were found.

CONCLUSIONS

The ECM/BCM ratio appears as a sensitive index that discriminates nutritional and/or hydration status in HD patients compared with age-gender-matched-controls. ECM/BCM ratios ≥1.20 are indicators of wasting and fluid overload in HD patients.

Bioelectrical Impedance Analysis-Derived Phase Angle Predicts Protein-Energy Wasting in Maintenance Hemodialysis Patients

OBJECTIVE(S)

To explore the validity of using bioelectrical impedance analysis (BIA)-derived 50 kHz phase angle (PhA) in predicting protein-energy wasting (PEW) in Chinese maintenance hemodialysis (MHD) patients.

DESIGN AND METHODS

The design was a cross-sectional study. A total of 173 of MHD patients and 173 healthy adults were enrolled in the study. The prevalence of PEW in patients was performed by the International Society of Renal Nutrition and Metabolism criteria. The PhA, body cell mass, fat mass, body fat percentage, fat-free mass, and extracellular water/total body water were measured by InBody S10 body composition analyzer. The biochemical indices and anthropometric measurements were assessed using the way published elsewhere. The PhA, other values of BIA and its relationship with age, visceral protein, anthropometric measurements of the MHD patients were compared with the healthy group. The independent variables for predicting PEW and its cutoff values were explored using logistic regression model and receiver operating characteristic curve analysis, respectively.

RESULTS

The MHD patients' PhA value was significantly lower than the healthy group (4.89°± 1.19 vs. 6.32°± 2.23, P < .01). A total of 34.1% MHD patients with PEW had significantly lower PhA values compared with well-nourished patients (P < .05). The PhA decreased more significantly with age in MHD (r = -0.35, P < .001), compared with controls (r = -0.26, P < .001). The PhA values were positively associated with nutritional indices related to serum albumin, prealbumin, fat-free mass, and mid-arm muscle circumference. PhA values were not associated significantly with fat mass and body fat percentage (P > .05). Multivariate logistic regression analysis showed that PhA and body mass index were independent predictors of PEW, but the PhA was the stronger predictor (odds ratio = 4.48, P < .05). Receiver operating characteristic curve analysis suggested that the optimal PhA cutoff value to predict PEW was 4.6°.

CONCLUSIONS

BIA-derived PhA appears to be a useful bioelectrical marker for predicting PEW in Chinese hemodialysis patients with a cutoff value of 4.6°.

Evaluating haemodialysis patient's nutritional status: Body mass index or body cell mass index?

OBJECTIVE

Evaluate which of two combinations of parameters based on International Society of Renal Nutrition and Metabolism recommendations could better identify patients with protein-energy wasting (PEW) and to compare the relationship of these two combinations with other clinical and body composition parameters.

METHODS

This was a multicentre longitudinal study with 24 months of follow-up. The PEW patients were characterized by: Group A (G_A ) - normalized protein catabolic rate (nPCR) < 1.0 g/kg per day, albumin <3.8 g/dL and body cell mass index (BCMI) < 6.4 kg/m² (n = 203); Group B (G_B ) - nPCR <1.0 g/kg per day, albumin <3.8 g/dL and body mass index (BMI) <23 kg/m² (n = 109). All the patients who did not meet these requirements were considered "well-nourished" (G_A : n = 1818; G_B : n = 3292).

RESULTS

When compared to the well-nourished patients, PEW patients in the G_A presented higher age, Kt/V, C-reactive protein, relative overhydration, fat tissue index (FTI); lower creatinine, albumin, nPCR, PTH, haemoglobin, phosphorus, calcium X phosphorus product, potassium, dry weight, BMI, BCMI, lean tissue index, %IDWG . In the G_B , well-nourished patients FTI was significantly higher. In Cox analysis, the combination with BCMI was a strong independent predictor of mortality in these patients (hazard ratio: 1.48; confidence interval: 1.00-2.19; P = 0.048), even after adjustment. Although G_B combination seemed to be also a predictor of death (hazard ratio: 2.67; confidence interval: 1.92-3.71; P < 0.001), when adjusted, the association remained no longer significant.

CONCLUSION

A new combination of parameters including protein intake, albumin and BCMI demonstrated significant associations with other nutrition and inflammation parameters as well as with mortality.

Clinical Significance of Phase Angle in Non-Dialysis CKD Stage 5 and Peritoneal Dialysis Patients

Background: Fluid overload and protein-energy wasting (PEW) are common in patients with end-stage renal disease (ESRD) and lead to a poor prognosis. We aimed to evaluate the volume and nutritional status of ESRD patients and to determine the clinical significance of phase angle (PhA). Methods: This study was a cross-sectional comparison of bioimpedance spectroscopy (BIS) findings in patients with non-dialysis chronic kidney disease (CKD) stage 5 (CKD5-ND, N = 80) and age/sex-matched peritoneal dialysis patients (PD, N = 80). PEW was defined as a PhA less than 4.5°. Results: The PhA was found to be positively associated with a geriatric nutritional risk index (GNRI, r = 0.561, p < 0.001), lean tissue index (LTI, r = 0.473, p < 0.001), and albumin (r = 0.565, p < 0.001) while OH/ECW (r = −0.824, p < 0.001) showed an inverse correlation. The CKD5-ND group had more overhydration (p = 0.027). The PD group had significantly higher PhA (p = 0.023), GNRI (p = 0.005), hemoglobin (p < 0.001), and albumin (p = 0.003) than the CKD5-ND group. The cut-off values predicting PEW were found to be 3.55 g/dL for albumin, 94.9 for GNRI, and 12.95 kg/m² for LTI in PD patients. Conclusions: This study demonstrated that PhA could be used as a marker to reflect nutritional status in patients with ESRD. Since BIS can inform both volume and nutritional status, regular monitoring will provide the basis for active correction of fluid overload and nutritional supplementation, which may improve outcomes in patients with ESRD.

Dietary inflammatory index is associated with serum C-reactive protein and protein energy wasting in hemodialysis patients: A cross-sectional study

BACKGROUND/OBJECTIVE

Malnutrition and inflammation are reported as the most powerful predictors of mortality and morbidity in hemodialysis (HD) patients. Diet has a key role in modulating inflammation and dietary inflammatory index (DII) is a new tool for assessment of inflammatory potential of diet. The aim of this study was to evaluate the application of DII on dietary intake of HD patients and examine the associations between DII and malnutrition-inflammation markers.

SUBJECTS/METHODS

A total of 105 subjects were recruited for this cross-sectional study. Anthropometric measurements, 3-day dietary recall, and pre-dialysis biochemical parameters were recorded for each subject. Subjective global assessment (SGA), which was previously validated for HD patients, and malnutrition inflammation score (MIS) were used for the diagnosis of protein energy wasting. DII was calculated according to average of 3-day dietary recall data.

RESULTS

DII showed significant correlation with reliable malnutrition and inflammation indicators including SGA (r = 0.28, P < 0.01), MIS (r = 0.28, P < 0.01), and serum C-reactive protein (CRP) (r = 0.35, P < 0.001) in HD patients. When the study population was divided into three subgroups according to their DII score, significant increasing trends across the tertiles of DII were observed for SGA score (P = 0.035), serum CRP (P = 0.001), dietary energy (P < 0.001), total fat (P < 0.001), saturated fatty acids (P < 0.001), polyunsaturated fatty acids (P = 0.006), and omega-6 fatty acids (P = 0.01) intakes.

CONCLUSION

This study shows that DII is a good tool for assessing the overall inflammatory potential of diet in HD patients.

Effect of the omega-3 fatty acid plus vitamin E supplementation on subjective global assessment score, glucose metabolism, and lipid concentrations in chronic hemodialysis patients

SCOPE

This study was conducted to determine the effects of omega-3 fatty acid plus vitamin E supplementation on subjective global assessment (SGA) score and metabolic profiles in chronic hemodialysis (HD) patients.

METHODS AND RESULTS

This randomized double-blind placebo-controlled clinical trial was conducted among 120 chronic HD patients. Participants were randomly divided into four groups to receive: (i) 1250 mg/day omega-3 fatty acid containing 600 mg eicosapentaenoic acid and 300 mg docosahexaenoic acid + vitamin E placebo (n = 30), (ii) 400 IU/day vitamin E + omega-3 fatty acids placebo (n = 30), (iii) 1250 mg omega-3 fatty acids/day + 400 IU/day vitamin E (n = 30), and (iv) omega-3 fatty acids placebo + vitamin E placebo (n = 30) for 12 wk. Fasting blood samples were taken at baseline and after 12-wk intervention to measure metabolic profiles. Patients who received combined omega-3 fatty acids and vitamin E supplements compared with vitamin E, omega-3 fatty acids, and placebo had significantly decreased SGA score (p < 0.001), fasting plasma glucose (p = 0.01), serum insulin levels (p = 0.001), homeostasis model of assessment insulin resistance (p = 0.002), and improved quantitative insulin sensitivity check index (p = 0.006).

CONCLUSION

Omega-3 fatty acids plus vitamin E supplementation for 12 wk among HD patients had beneficial effects on SGA score and metabolic profiles.