Norms and correlates of bioimpedance phase angle in healthy human subjects, hospitalized patients, and patients with liver cirrhosis

Bioelectrical impedance vector analysis evaluates cellularity and hydration in cirrhotic patients

BACKGROUND

Malnutrition in cirrhotic patients is correlated with mortality and a better response to liver transplantation. However, recovery of the nutritional status in these patients is a challenge due to the difficulty in establishing a reliable nutritional diagnosis. The bioelectrical impedance vector analysis (BIVA) method appears as a feasible tool in clinical practice to define the physiological state of cirrhotic patients by assessing hydration and body cellularity.

AIM

To evaluate body composition in cirrhotic patients using BIVA.

METHODS

This retrospective cross-sectional study was carried out by following cirrhotic outpatients at a hospital in Porto Alegre, Brazil. A tetrapolar bioelectrical impedance analysis device was used to evaluate cellularity and hydration and to perform the BIVA. The BIVA graphic was elaborated by software and for statistical analysis a significance level of 5% (P ≤ 0.05) was considered.

RESULTS

One hundred and ninety patients, 61.1% males, with a mean age of 56.6 ± 11.0 years, were evaluated. Of these, 56.3% had Child-Turcotte-Pugh (CTP) A score, and the prevalent etiology was hepatitis C virus (47.4%). The patients were classified according to cellularity and hydration by the quadrants and ellipses of the BIVA method, quadrant 1 (47.9%); quadrant 2 (18.9%); quadrant 3 (14.2%); and quadrant 4 (18.9%). Those classified in quadrant 1 and 2 had a higher phase angle compared to those in quadrants 3 and 4 (P < 0.001). Quadrant 2 patients had a lower average age than the other groups. The association with CTP score showed that patients in quadrant 2 had a higher proportion of CTP A, and those in quadrant 4 had a higher proportion of CTP C (P < 0.052).

CONCLUSION

The BIVA method allows identification of the cellularity and hydration status of cirrhotic patients, and its association with clinical factors determines the disease severity, age and prognostic index.

The Predictive Role of Raw Bioelectrical Impedance Variables in Disordered Eating Attitudes in Female Ballet Dance Students

The present study used receiver operating characteristic (ROC) curve analysis to investigate the accuracy of body composition and raw bioelectrical impedance analysis (BIA) in correctly classifying disordered eating attitudes (DEA) in dance students. Participants were 81 female dancers assigned in two groups: beginner training (BT; age (mean ± SD) = 10.09 ± 1.2 years, n = 32) and advanced training (AT; age = 15.37 ± 2.1 years, n = 49). Fat mass (FM) was estimated by Slaughter's equation and skeletal muscle with Poortman's equation. Impedance (Z), resistance (R), reactance (Xc) and phase angle (PhA) were obtained through multifrequency BIA at a frequency of 50 kHz. Fat-free mass (FFM) was assessed using Sun's equation. For evaluation of DEA, the Eating Attitudes Test-26 (EAT-26) questionnaire was performed. We defined an EAT-26 score ≥ 20 as positive for DEA. Comparisons between groups were performed by a one-way ANOVA test or Kruskall-Wallis test. Spearman's rank correlation coefficients were performed to assess associations between variables. ROC curve analysis was utilized to test the accuracy of body composition and BIA variables in predicting DEA. In the BT group, Xc and PhA demonstrated high accuracy in predicting DEA with an area under the curve (AUC) of 0.976 (95% confidence interval (CI): 0.85-1.00) and 0.957 (95% CI: 0.82-0.99), respectively, (both p < 0.0001). FFM Sun had an AUC of 0.836 (95% CI: 0.66-0.94) (p < 0.0001) in the BT group and FFM Slaughter was 0.797 (95% CI: 0.66-0.90) (p < 0.001) in the AT group. Reactance and Phase angle were excellent and useful predictors of DEA in the BT group.

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.

Phase Angle Is an Independent Predictor of 6-Month Mortality in Patients With Decompensated Cirrhosis: A Prospective Cohort Study

BACKGROUND

This study aimed to evaluate the nutrition status through phase angle (PA) and its association with mortality in patients with decompensated cirrhosis.

METHODS

A prospective cohort study was performed with hospitalized decompensated cirrhotic patients. Nutrition status was assessed by PA, bioelectrical impedance vector analysis (BIVA), and Subjective Global Assessment (SGA) within 72 hours of hospital admission. The best PA cutoff point for malnutrition diagnosis was determined by ROC curve analysis, considering the SGA as the reference standard. Predictors of 6-month mortality were identified using Cox proportional hazards models, adjusted for Child-Pugh and MELD scores, and hepatocellular carcinoma.

RESULTS

This study included 97 patients, 63% male (n = 61), with a mean age of 60.1 ± 10.3 years. The median follow-up time of patients was 11.2 months (IQR, 2.4-21). Overall mortality was 58.8% (n = 57) and 6-month mortality was 35.1% (n = 34). Nutrition assessment according to BIVA indicated a risk for cachexia and normal hydration. Patients with values of PA ≤5.52° were considered malnourished. Malnourished patients according to PA (58.8%, n = 57) had a higher risk of 6-month mortality (HR = 3.44; 95% CI, 1.51-7.84; P = .003), and each increase of 1° in PA values was associated with a reduction of 53% in 6-month mortality risk.

CONCLUSIONS

The PA is an independent predictor of 6-month mortality in patients with decompensated cirrhosis. Therefore, PA may be useful to assess the nutrition status and identify patients at the highest risk of mortality in clinical practice.

MALNUTRITION IN CIRRHOSIS: ASSOCIATION WITH ETIOLOGY AND HEPATOCELLULAR DYSFUNCTION

BACKGROUND

The protein-energy malnutrition alters the prognosis of patients with cirrhosis. Its prevalence may vary according to the etiology of liver disease, it´s severity and the evaluation of the method applied. The infection by the hepatitis C virus (HCV) and alcoholism are the main etiologies of cirrhosis and result in a significant morbidity and mortality.

OBJECTIVE

To evaluate the nutritional status of patients with cirrhosis according the liver disease etiology and severity.

METHODS

It is a prospective study, in which the sample was for convenience and consisted of patients with cirrhosis, infected by HCV or alcoholic etiology. The nutritional status evaluation was carried out through anthropometry, food consumption, bioelectrical impedance (BIA) and subjective global assessment (SGA). The anthropometric data evaluated were weight, height, body mass index (BMI), triceps skinfold (TSF), circumference of the arm (CA), non-dominant handshake strength (FAM) and the adductor pollicis muscle thickness (APM). Patients were classified according to the severity of liver disease, using the Child-Pugh and Model for End-stage Liver Diseases (MELD) scores.

RESULTS

Ninety patients with cirrhosis were evaluated, 47 with HCV and 43 with alcoholic etiology. The prevalence of protein-calorie malnutrition ranged from 10.9% to 54.3% in the HCV group and from 4.7% to 20.9% in the alcoholic group, depending on the method used for evaluation. The group with HCV infection presented a higher malnutrition prevalence in comparison to the alcoholic in the following evaluations: TSF (P<0.001), phase angle (PA) (P=0.016) and SGA (P=0.010). PA values were lower in patients with viral cirrhosis (5.68±1.05) when compared to those with alcoholic etiology (6.61±2.31) (P=0.016). When all patients were analyzed, regardless of etiology, an inversely correlation was observed among Child-Pugh score and PA values (P=0.018).

CONCLUSION

HCV cirrhosis showed worse nutritional parameters in comparison to alcoholic etiology; however, the PA was associated with worse liver function in both etiologies.

Obesity Affects the Association of Bioelectrical Impedance Phase Angle With Mortality in People Living With HIV

Bioelectrical impedance analysis phase angle (BIA-PA) is a valid indicator of mortality risk in people living with HIV; however, it is not known whether BIA-PA is valid for people living with HIV who are overweight or obese. We assessed whether BIA-PA differentially predicted mortality by body mass index category in participants receiving clinical care at a single site between 2000 and 2012. Change in BIA-PA from the highest versus last available phase angle was assessed using multivariate logistic regression models. Eight hundred ninety participants were included in the final analyses, with 102 deaths recorded during the study period. Decline in BIA-PA was associated with mortality in underweight and normal weight participants but not in overweight or obese participants. Additional investigation is warranted to determine the appropriate clinical BIA-PA equations and parameters to identify overweight and obese patients with increased mortality risk.

Can Phase Angle in Newborns at Neonatal Intensive Care Units Be an Indicator of Mortality and Prognosis?

BACKGROUND

The bioelectrical impedance (BI) phase angle (PA), analyzed directly through BI analysis (BIA), is determined by tissue cellularity, representing a direct measure of cellular stability and, for this reason, has been studied and considered as an indicator of prognosis and nutrition status in adults and children.

OBJECTIVE

We aimed to determine if PA can be an indicator of mortality and prognosis in newborns admitted to the neonatal intensive care unit (NICU).

METHODS

Transversal study conducted at a public NICU in Curitiba, Paraná, Brazil. All newborns, preterm and term, were considered eligible for the study if admission to the NICU occurred by the first hour of life. The Score for Neonatal Acute Physiology II, as well as the Perinatal Extension version, were developed to assess the risk of mortality for all newborns, measured within 12 hours of admission. BIA measurements were conducted using the tetrapolar BioScan Maltron 916, with single-frequency (50 kHz) tetrapolar BI. PA was calculated as the arc tangent: (Xc/R) x 180°/π.

RESULTS

BIA was measured during the first 24 hours of admission for all newborns (n = 93), repeated between 24 and 48 hours (n = 79) and again after 7 days (n = 55), always when possible. PA measurements decreased in the first 48 hours in premature newborns, particularly among those who died. The premature newborns also showed a significant decrease from the first to the last PA measurement (P = .001). In addition, whereas full-term newborns showed an increase of PA at 1 week of life, preterm infants continued to have a decrease in values. For preterm newborns, PA measurements decreased and more sharply so for those who died. This result should be viewed with caution given the small number of deaths, but it should be investigated to understand the role of PA in the prognosis of NICU newborns.

CONCLUSIONS

The absolute value of PA during the first 24 hours of life was not a good marker for severity or mortality. However, the decrease of PA between different moments of evaluation was a good marker of severity. The decrease of PA in the first 48 hours in premature newborns, and that when the decrease is more pronounced, may be indicative of mortality. The difference in PA values between these newborns is probably a significant variable for mortality and prognosis and not a cutoff value.

Independent Association of Phase Angle with Fasting Blood Glucose and Hemoglobin A1c in Korean Type 2 Diabetes Patients

The relationship between phase angle (PhA) of bioelectrical impedance analysis (BIA) and glycemic parameters in diabetes mellitus (DM) patients has not been well studied. To evaluate the prognostic value of the PhA from BIA as a glycemic marker, we investigated the relationship of PhA with various variables such as age, body mass index (BMI), and glycemic parameters in Korean patients with type 2 DM (T2DM). We evaluated the anthropometric data, body composition, glycemic parameters, and PhA of 321 T2DM patients aged 30–83 years. The patients were classified by sex into men (n = 133) and women (n = 188). General linear models identified the independent effects of PhA after covarying for age, sex and BMI. The PhA, body cell mass (BCM), extracellular mass (ECM), lean body mass, intracellular water (ICW), extracellular water (ECW), total body water (TBW), fasting blood glucose, and hemoglobin A1c (HbA1c) of T2DM Korean patients were significantly higher in men than in women. However, fat mass, ECM/BCM, ECW/ICW, ECW/TBW, and serum insulin were significantly higher in women than in men. Statistically significant independent associations were observed between PhA and age, BCM, ECM, ECM/BCM, ICW, ECW, ECW/ICW, and ECW/TBW for both sexes. There was no significant association between PhA and BMI the patients. Glycemic parameters, such as HbA1c and fasting blood glucose were independently associated with PhA. These results suggest that PhA could be an indicator for assessing ability to control fasting blood glucose in T2DM patients in Korea.

Phase Angle as an Indicator of Sarcopenia, Malnutrition, and Cachexia in Inpatients with Cardiovascular Diseases

Malnutrition is associated with sarcopenia, cachexia, and prognosis. We investigated the usefulness of phase angle (PhA) as a marker of sarcopenia, cachexia, and malnutrition in 412 hospitalized patients with cardiovascular disease. We analyzed body composition with bioelectrical impedance analysis, and nutritional status such as controlling nutritional status (CONUT) score. Both skeletal muscle mass index (SMI) and PhA correlated with age, grip strength and knee extension strength (p < 0.0001) in both sexes. The SMI value correlated with CONUT score, Hb, and Alb in males. Phase angle also correlated with CONUT score, Hb, and Alb in males, and more strongly associated with these nutritional aspects. In females, PhA was correlated with Hb and Alb (p < 0.001). In both sexes, sarcopenia incidence was 31.6% and 32.4%; PhA cut-off in patients with sarcopenia was 4.55° and 4.25°; and cachexia incidence was 11.5% and 14.1%, respectively. The PhA cut-off in males with cachexia was 4.15°. Multivariate regression analysis showed that grip strength and brain natriuretic peptide (BNP) were independent determinants of SMI, whereas grip strength, BNP, and Hb were independent determinants of PhA. Thus, PhA appears to be a useful marker for sarcopenia, malnutrition, and cachexia in hospitalized patients with cardiovascular disease.

Utility of bio-electrical impedance vector analysis for monitoring treatment of severe acute malnutrition in children

BACKGROUND & AIMS

Change in hydration is common in children with severe acute malnutrition (SAM) including during treatment, but is difficult to assess. We investigated the utility of bio-electrical impedance vector analysis (BIVA), a quick non-invasive method, for indexing hydration during treatment.

METHODS

We studied 350 children 0·5-14 years of age with SAM (mid-upper arm circumference <11·0 cm or weight-for-height <70% of median, and/or nutritional oedema) admitted to a hospital nutrition unit, but excluded medically unstable patients. Weight, height (H), resistance (R), reactance (Xc) and phase angle (PA) were measured and oedema assessed. Similar data were collected from 120 healthy infants and preschool/school children for comparison. Means of height-adjusted vectors (R/H, Xc/H) from SAM children were interpreted using tolerance and confidence ellipses of corresponding parameters from the healthy children.

RESULTS

SAM children with oedema were less wasted than those without (p < 0·001), but had BIVA parameters that differed more from those of healthy children (P < 0·05) than those non-oedematous. Initially, both oedematous and non-oedematous SAM children had mean vectors outside the reference 95% tolerance ellipse. During treatment, mean vectors migrated differently in the two SAM groups, indicating fluid loss in oedematous patients, and tissue accretion in non-oedematous patients. At admission, R/H was lower (oedematous) or higher (non-oedematous) among children who died than those who exited the hospital alive.

CONCLUSIONS

BIVA can be used in children with SAM to distinguish tissue-vs. hydration-related weight changes during treatment, and also identify children at high risk of death enabling early clinical interventions.

Phase Angle: Could Be an Easy Tool to Detect Low-Grade Systemic Inflammation in Adults Affected by Prader-Willi Syndrome?

Prader-Willi syndrome (PWS) is the most common genetic inherited obesity syndrome. Obesity-related complications, mostly related to chronic low-grade systemic inflammation (LGI), are the commonest cause of mortality and morbidity in PWS adults. Phase angle (PhA) is an easy tool to screen a state of LGI in healthy subjects and in subjects with obesity and is obtained from bioelectrical impedance analysis (BIA). The aim of this study was to validate the PhA in PWS adults as a potential biomarker of LGI. In this single-center, cross-sectional study, fifteen PWS adults (six males, aged 19-41 years, and body mass index (BMI) 31.0-68.0 Kg/m2) and fifteen control subjects matched by gender, age, and BMI were evaluated. PhA values were significantly lower (p < 0.001), while high-sensitivity C-reactive protein (hs-CRP) levels were significantly higher (p < 0.001) in PWS adults compared with controls (p < 0.001), without a gender difference in the latter. After adjustment for gender, BMI, and waist circumference, significant correlation was found between PhA and hs-CRP levels (r = -0.69, p = 0.01). At the ROC analysis, the threshold value of PhA predicting the highest hs-CRP levels above the median value was found at PhA ≤ 4.8° (p = 0.01; AUC, 0.82; standard error, 0.12; 95% CI, 0.58 to 1.00). These results suggest that PWS adults had a significant higher degree of LGI compared with their counterparts. Moreover, our finding suggest that PhA is a valid biomarker of LGI also in PWS adults.

Phase Angle as a Marker of Muscular Strength in Breast Cancer Survivors

BACKGROUND

accurate prognostic tools are relevant for decision-making in cancer care. Objective measures, such as bioelectrical impedance (BI), have the potential to improve prognostic accuracy for these patients. This cross-sectional study aimed to investigate whether phase angle (PhA) derived from the electrical properties of the body tissues is a predictor of muscular strength in breast cancer survivors (BCS).

METHODS

a total of 41 BCS (age 54.6 ± 9.2 years) were evaluated. PhA, obtained at frequency 50 kHz, was assessed with BI spectroscopy, and muscular strength with a handgrip dynamometer. Moderate-to-vigorous physical activity (MVPA) was assessed using the International Physical Activity Questionnaire (IPAQ). Measurements were performed in the morning after an overnight fast.

RESULTS

linear regression analysis showed that PhA accounted for 22% (r² = 0.22) of muscular strength variance. PhA remained a borderline predictor of muscular strength variance independently of age and MVPA.

CONCLUSIONS

the findings of this study suggest that PhA is a significant predictor of maximal forearm isometric strength and a potential indicator of disease-related functionality in BCS.

Impact of phase angle on postoperative prognosis in patients with gastrointestinal and hepatobiliary-pancreatic cancer

OBJECTIVE

Phase angle (PhA), by bioelectrical impedance analysis, has been used in patients with several diseases; however, its prognostic value in patients with gastrointestinal (GI) and hepatobiliary-pancreatic (HBP) cancer is unclear. The aim of the present study was to investigate the effects of PhA on postoperative short- outcomes and long-term survival in these patients.

METHODS

This retrospective study reviewed data from 501 patients with GI and HBP cancers who underwent first resection surgery. The data were divided into the following groups according to the preoperative PhA quartile values by sex: high-PhA group with the highest quartile (Q4), normal-PhA group with middle quartiles (Q3 and Q2), and low-PhA group with the lowest quartile (Q1). Preoperative nutritional statuses, postoperative short-term outcomes during hospitalization, and 5-y survival between three groups were compared. Cox proportional hazard models were used to evaluate the prognostic effect of PhA.

RESULTS

PhA positively correlated with body weight, skeletal muscle mass, and handgrip strength, and negatively correlated with age and levels of C-reactive protein. The low-PhA group showed a higher prevalence of malnutrition (48%) than normal-PhA (25%), and high-PhA groups (9%; P < 0.001). The incidence of postoperative severe complications was 10% for all patients (14% in low-PhA, 12% in normal-PhA, and 4% in high-PhA; P = 0.018). The incidence of prolonged stays in a postoperative high-care or intensive care unit was 8% in all patients (16% in low-PhA, 8% in normal-PhA, and 2% in high-PhA; P < 0.001). The 5-y survival rate was 74% in all patients (68% in low-PhA, 74% in normal-PhA, and 79% in high-PhA; P < 0.001). The multivariate analysis demonstrated that a low-PhA group was an independent risk factor for mortality (hazard ratio, 1.99; 95% confidence interval, 1.05-3.90; P = 0.034).

CONCLUSION

PhA is a useful short-term and long-term postoperative prognostic marker for patients with GI and HBP cancers.

Reduction of fat free mass index and phase angle is a risk factor for development digital ulcers in systemic sclerosis patients

INTRODUCTION/OBJECTIVES

This study aims to evaluate the role of fat free mass index (FFMI) and phase angle (PhA) as markers to predict occurrence of new digital ulcers in systemic sclerosis (SSc) patients.

METHODS

Body composition evaluation from bioelectrical impedance and clinical assessment were performed in SSc patients at enrollment and after 12 months follow-up.

RESULTS

Seventy-nine SSc patients (67 female) with a mean age of 53 ± 13 years were enrolled. In SSc patients with a digital ulcers history, FFMI value is lower (p < 0.05) and phase angle (PhA) value is higher (p < 0.01) than SSc patients without a digital ulcers history. After 12 months of follow-up, 30 patients (38%) presented at least one new episode of digital ulcers. Patients with reduced FFMI had a relative risk of 6.7 for new digital ulcers (CI 2.1-21.8, p < 0.001). Patients with reduced PhA had a relative risk of 10.1 for new digital ulcers (CI 3.5-29.5, p < 0.0001). In multivariate analysis, FFMI and PhA were associated with major vascular complication (digital ulcers, pulmonary arterial hypertension, and scleroderma renal crisis). FFMI loss, assessed as delta between follow-up and baseline, is higher in SSc with short duration (≤ 3 years) than SSc patients with long duration [0.4 (0-0.50) vs - 0.10 (- 0.2-0)].

CONCLUSION

In SSc patients, reduction of the FFMI and PhA represents after 12 months a risk factor for development of new digital ulcers and major vascular complication. Key Points • Fat free mass index represents a risk factor for development of digital ulcers • Phase angle represents a risk factor for development of digital ulcers • Body compositions in systemic sclerosis are a marker of activity disease.

Phase angle as a predictor of functional outcomes in patients undergoing in-hospital rehabilitation after hip fracture surgery

OBJECTIVES

To evaluate the association between the phase angle and functional outcomes in patients after in-hospital postoperative rehabilitation for fragility hip fracture.

METHODS

A prospective observational study was conducted in 68 patients over 65 years of age who had undergone a two-week postoperative rehabilitation for hip fracture. Phase angle of the non-fractured limb was used to reduce the error caused by postoperative edema. Participants were divided into groups according to phase angle terciles. Multivariable linear regression models adjusted for relevant factors known to affect functional outcomes after hip fracture were performed to identify the association between phase angle of the non-fractured limb and functional outcomes at discharge as evaluated the Functional Ambulation Category and Berg Balance Scale.

RESULTS

The mean age of this study population was 81.9 ± 6.2 years and the average phase angle of the non-fractured limb was 3.6 ± 1.3°. The lowest tercile of phase angle (<3.0°) was independently associated with worse functional outcomes as measured by the Functional Ambulation Category and Berg Balance Scale at discharge (adjusted coefficient [β] = -0.287, P = 0.004; β = -0.172, P = 0.049, respectively) after adjusting for relevant covariates.

CONCLUSIONS

Low phase angle of the non-fractured limb was independently associated with worse functional outcomes at rehabilitation discharge in patients who undergoing hip fracture surgery. Phase angle may reflect both the pre-fracture body composition and functional status. It is a useful indicator for functional outcomes after postoperative rehabilitation for fragility hip fracture.

Clinical implications with tolvaptan on monitored bioimpedance-defined fluid status in patients with cirrhotic ascites: an observational study

Background

Prognostic value or clinical implications of fluid status monitoring in liver cirrhosis are not fully elucidated. Tolvaptan, an orally available, selective vasopressin V2-receptor antagonist approved for hyponatremia in the United States and European Union. It is also used for cirrhotic ascites at a relatively low dose (3.75 mg to 7.5 mg) in Japan, exerts its diuretic function by excreting electrolyte-free water. We hypothesized that bioimpedance-defined dynamic changes in fluid status allow prediction of response of V2 antagonism and survival in cirrhotic patients.

Methods

In this prospective observational study, 30 patients with decompensated liver cirrhosis who were unresponsive to conventional diuretics were enrolled. Detailed serial changes of body composition that were assessed by using non-invasive bioimpedance analysis (BIA) devices, along with biochemical studies, were monitored at 5 time points.

Results

Sixteen patients were classified as short-term responders (53%). Rapid and early decrease of BIA-defined intracellular water, as soon as 6 h after the first dose (ΔICW_BIA%-6 h), significantly discriminated responders from non-responders (AUC = 0.97, P < 0.0001). ΔICW_BIA%-6 h was highly correlated with the change of BIA-derived phase angle of trunk, e.g. reduced body reactance operated at 50 kHz after 24 h of the first dose of tolvaptan. Lower baseline blood urea nitrogen and lower serum aldosterone were predictive of a rapid and early decrease of ICW_BIA. A rapid and early decrease of ICW_BIA in response to tolvaptan was also predictive of a better transplant-free survival.

Conclusions

BIA-defined water compartment monitoring may help predict short-term efficacy and survival in decompensated cirrhotic patients treated with tolvaptan.

Systematic review with meta-analysis: Nutritional screening and assessment tools in cirrhosis

BACKGROUND & AIMS

Disease-related malnutrition is common in cirrhosis. Multiple studies have evaluated nutritional screening tools (NSTs, rapid bedside tests targeting who needs assessment) and nutritional assessment tools (NATs, used in diagnosing malnutrition) as predictors of clinical outcome in this population. We performed a systematic review and meta-analysis of this literature with the aim of summarising the varying definitions of malnutrition across studies, the available evidence for NSTs and the ability of NSTs and NATs to predict clinical outcomes in cirrhosis.

METHODS

The primary outcome measures were pre- and post-transplant mortality with a range of secondary outcomes. Inclusion: cirrhosis over age 16. Exclusion: >25% with hepatocellular carcinoma, primarily laboratory test-based NATs or lack of screening, assessment or outcome criteria.

RESULTS

Eight thousand eight hundred fifty patients were included across 47 studies. Only 3 studies assessed NSTs. Thirty-two definitions for malnutrition were utilised across studies. NATs predicted pre-transplant mortality in 69% of cases that were assessed with a risk ratio (RR) of 2.38 (95% CI 1.96-2.89). NATs were prognostic for post-transplant mortality only 28% of the times they were assessed, with a RR of 3.04 (95% CI 1.51-6.12).

CONCLUSIONS

The cirrhosis literature includes limited data on nutrition screening and multiple definitions for what constitutes malnutrition using NATs. Despite this discordance, it is clear that malnutrition is a valuable predictor of pre-transplant mortality almost regardless of how it is defined. We require clinical and research consensus around the definition of malnutrition and the accepted processes and cut-points for nutrition screening and assessment in cirrhosis.

Bioimpedance spectroscopy for fluid status assessment in patients with decompensated liver cirrhosis: Implications for peritoneal dialysis

Bioimpedance spectroscopy (BIS) is routinely used in peritoneal dialysis patients and might aid fluid status assessment in patients with liver cirrhosis, but the effect of ascites volume removal on BIS-readings is unknown. Here we determined changes in BIS-derived parameters and clinical signs of fluid overload from before to after abdominal paracentesis. Per our pre-specified sample size calculation, we studied 31 cirrhotic patients, analyzing demographics, labs and clinical parameters along with BIS results. Mean volume of the abdominal paracentesis was 7.8 ± 2.6 L. From pre-to post-paracentesis, extracellular volume (ECV) decreased (20.2 ± 5.2 L to 19.0 ± 4.8 L), total body volume decreased (39.8 ± 9.8 L to 37.8 ± 8.5 L) and adipose tissue mass decreased (38.4 ± 16.0 kg to 29.9 ± 12.9 kg; all p < 0.002). Correlation of BIS-derived parameters from pre to post-paracentesis ranged from R² = 0.26 for body cell mass to R² = 0.99 for ECV. Edema did not correlate with BIS-derived fluid overload (FO ≥ 15% ECV), which occurred in 16 patients (51.6%). In conclusion, BIS-derived information on fluid status did not coincide with clinical judgement. The changes in adipose tissue mass support the BIS-model assumption that fluid in the peritoneal cavity is not detectable, suggesting that ascites (or peritoneal dialysis fluid) mass should be subtracted from adipose tissue if BIS is used in patients with a full peritoneal cavity.

Phase angle could be a marker of microvascular damage in systemic sclerosis

OBJECTIVES

Systemic sclerosis (SSc) is an autoimmune disease characterized by endothelial dysfunction with fibrosis of skin and internal organs. Integrity of the endothelial cell is important to its physiologic function such as production of angiogenetic factors. The aim of this study was to assess whether phase angle (PhA) is altered in patients with SSc and whether its values correlate with vascular endothelial growth factor (VEGF) and digital microvascular damage.

METHODS

Patients with SSc and matched healthy controls underwent VEGF determination and bioimpedentiometry (BIA) for PhA assessment. Clinical assessment, disease activity index (DAI), disease severity scale, and nailfold videocapillaroscopy (NCV) were performed in patients with SSc.

RESULTS

Fifty-five patients (46 women) with a mean age of 53.2 ± 13.7 y were studied. The mean value of VEGF was significantly higher in patients with SSc than in the healthy controls (240.3 ± 149.5 versus 139 ± 87.5; P = 0.035). The mean value of PhA was significantly lower in the patient grouop than in the healthy controls (4.51 ± 0.87 versus 5.22 ± 0.55; P < 0.0001). A significant positive correlation was found between VEGF and PhA (P = 0.009, beta coefficient = 1.48) in SSc patients. A negative correlation between VEGF and DAI (P = 0.048, β coefficient = 0.48) was found. PhA median value was significantly (P = 0.006) lower in patients with late pattern SSc (4.2 [2.5-5.3]). PhA median value was significantly (P < 0,0001) lower in patients with digital ulcers (DUs; 4.2 [2.5-5.3]) than in those without DUs (3.80 [2.50-5] versus 4.75 [2.80-7.3]). These data were confirmed in both female and male patients.

CONCLUSIONS

The evaluation of VEGF with PhA, NVC, and DUs could be useful to estimate cellular and microvascular damage in patients with SSc.

The influence of diet therapeutic intervention on the sarcopenic index of patients with metabolic syndrome

Introduction

The published data showed the importance of metabolic control in preventing complications in metabolic syndrome (MS) and the role of nutritional medical therapy in glycemic control and in the control of dyslipidemia, hypertension, weight loss/normalization (in overweight or malnourished subjects).

Objectives

This study follows the evolution of sarcopenic index (SI) and other clinical parameters (body mass index (BMI), homeostasis evaluation index (HOMA index)) correlated with MS after diet therapy or diet therapy combined with sports, in patients with MS.

Patients and methods

Our research was conducted during 12 months, on 110 patients >18 years of age, with HOMA index>2, divided into three groups: control group (CG, N=20), diet therapy group (DTG, N=58), diet therapy and sports group (DTSG, N=32). HOMA index for insulin resistance was calculated as the product of resting plasma insulin (in microunits/milliliter) and plasma glucose (in millimoles/liter), divided by 22.5. SI was determined using BIA, as being the ratio between muscle mass and fat mass, measured in cm²/m².

Results

A significant decrease of BMI (p<0.05) in DTG (from 31.63 to 24.50) and DTSG (from 30.18 to 24.17) vs. CG was observed (Pearson coefficient r=0.281, p<0.001). Weight status changed significantly (p<0.05) in the high-risk patients. There was a significant decrease of HOMA index (p<0.05) in DTG (from 5.93 to 2.57), DTSG (from 3.93 to 2.23), and in CG an increase was observed (from 3.15 to 3.37).

Conclusion

The best results in the prevention/ treatment of sarcopenia in MS patients were obtained for DTSG, which benefited from both the positive effect of diet and physical activity.

The association of bioimpedance analysis parameters with the outcomes of critically ill patients

BACKGROUND

The association between bioimpedance analysis (BIA) parameters and the outcomes of critically ill patients was explored through a retrospective investigation.

METHODS

The study enrolled patients in the intensive care units of our hospital who had a record of BIA measurements as well as disease severity scores assessed by Acute Physiology and Chronic Health Evaluation II (APACHE II), Simplified Acute Physiology Score II (SAPS II) and Sequential Organ Failure Assessment (SOFA). The associations between clinical conditions, outcomes and BIA parameters were analysed. The relationship between individual bioimpedance values and the current frequencies fit well to a natural logarithmic function, providing a regression coefficient S value. Other parameters obtained from the BIA measurements included phase angle (PA), the ratio of bioimpedance at high and low frequencies (IR), extracellular water (ECW), intracellular water (ICW) and total body water (TBW).

RESULTS

Among 201 enrolled patients, the 90-day in-hospital mortality was 35.8%. Compared to the survivors at 7-days, for the non-survivors, the IR, S value, ratio of ECW/weight and ratio of ECW/TBW were higher, and the PA was lower (P < 0.05). Compared to the survivors at 90-days, for the non-survivors, the IR, S value and ratio of ECW/weight were higher, and the PA was lower (P < 0.05). Multinomial logistic regression analysis results showed that only SAPS II and S value were independent risk factors for 7-day and 90-day death (P < 0.01). When analysed by ROC, the AUC of the S value for predicting 7-day and 90-day death was non-significantly lower than SAPS II (S vs. SAPS II, 0.729 vs. 0.747 (7-day); 0.701 vs. 0.779 (90-day), P > 0.05). Importantly, both the 7-day and the 90-day mortality in patients with S values ≤-25.5 were 0; for the others, the mortality increased with the rise of S value. For patients with SAPS II ≤33, the mortality varied minimally; and for patients with SAPS II >55, the mortality was 100%.

CONCLUSIONS

The S value and SAPS II are independent risk factors for 7-day and 90-day death in critically ill patients; the former may have a greater negative predictive value, while the latter may have a greater positive predictive value.

Nutritional prognostic factors for survival in amyotrophic lateral sclerosis patients undergone percutaneous endoscopic gastrostomy placement

Objective: There are conflicting data on nutritional factors influencing survival in amyotrophic lateral sclerosis (ALS) patients after percutaneous endoscopic gastrostomy (PEG) placement. We performed an observational cross-sectional study evaluating body mass index (BMI) categories and cholesterol levels as prognostic factors for survival after PEG. Moreover, we assessed body composition in a subgroup of patients to better explain the influence of BMI on survival. Methods: Neurological and nutritional parameters were evaluated at the time of PEG implantation in 47 consecutive patients. Moreover, body composition was evaluated in a subgroup of 22 patients by bioelectrical impedance analysis. Survival was calculated as the time from the PEG placement to death. Results: Underweight patients had a significantly increased risk of death as compared to normal-weight patients using Cox regression analysis [HR = 3.37 (1.29-8.81); p = 0.04]. Similarly, older age at the onset of symptoms significantly increased the risk of death [HR = 1.07 (1.02-1.12); p = 0.001]. Neither overweight/obesity nor hypercholesterolemia affected survival. All ALS patients showed an altered body composition compared to the general population. In addition, a BMI <18.5 kg/m² identified patients with a significant reduction of body cell mass (BCM) and phase angle (PhA) compared to patients with normal BMI taken as the reference value. Conclusions: In the later stages of the disease, only a BMI < 18.5 kg/m² and older age at symptom onset had a prognostic value on survival. Dyslipidemia did not affect survival. The low BCM and PhA characterizing underweight patients support the role of BMI as a predictor of survival.

Anthropometrical and Bioelectrical Impedance Analysis Parameters in Anorexia Nervosa Patients' Nutritional Status Assessment

Background and Objectives: Body mass index (BMI) is still the only recommended measurable nutritional status assessment parameter in anorexia nervosa (AN). The aim of this study was to measure other anthropometrical and bioelectrical impedance analysis (BIA) parameters in AN patients and to evaluate their nutritional status assessment value. Materials and Methods: The 46 AN female patients were examined at the beginning of hospitalization and followed-up in three measurements (in 6 ± 2 weeks’ intervals). Anthropometrical assessment was based on BMI, circumferences of arm, calf, thigh, hips, waist, their ratio (waist-to-hip ratio (WHR)), and a skinfold test over biceps and triceps muscle, under the scapula, over the hip, and 2 cm from the umbilicus. The BIA parameters included phase angle (PA), membrane capacitance (Cm), and impedance at 200 kHz, and a 5 kHz ratio (Z_200/5). Results: In the 1st measurement, BMI correlated with all anthropometric and BIA parameters (p < 0.05). For BIA parameters, the correlation included arm circumference and WHR (p < 0.05). In the follow-up, significant changes were observed in BMI and all BIA parameters. The correlation between BMI and all BIA parameters was present in the 2nd and 3rd measurements (p < 0.05). In the 4th measurement, BMI correlated only with Cm (p = 0.0114). Comparison of BIA parameters according to the state of starvation (BMI < 16.0 kg/m²) revealed that all studied BIA parameters were characterized by statistically significant sensitivity and specificity in the detection of this condition (p < 0.05), except PA in the 4th measurement (p = 0.2099). Conclusions: Selected BIA and anthropometrical parameters could be used for AN patients’ assessment. The study confirmed dynamic changes of BIA parameters during the follow-up. They could be useful in the detection of the state of starvation.

An evaluation of phase angle, bioelectrical impedance vector analysis and impedance ratio for the assessment of disease status in children with nephrotic syndrome

Background

Oedema, characterized by accumulation of extracellular water (ECW), is one of the major clinical manifestations in children suffering from nephrotic syndrome (NS).

The lack of a simple, inexpensive and harmless method for assessing ECW may be solved by the use of the bioelectrical impedance analysis (BIA) technique.

The aims of this study were to examine whether phase angle (PA), bioelectrical impedance vector analysis (BIVA) and the impedance ratio (IR) reflect change in disease status in children with NS.

Methods

Eight children (age range: 2–10 years) with active NS (ANS group) were enrolled. In five of these (ANS* subgroup), impedance was also measured at remission (NSR group). Thirty-eight healthy children (age range: 2–10 years) were included as healthy controls (HC group). Whole-body impedance was measured with a bioimpedance spectroscopy device (Xitron 4200) with surface electrodes placed on the wrist and ankle.

Results

Values of PA, BIVA and IR were found to be significantly lower (p-value range < 0.001 to < 0.01) in the ANS patients compared to the HC and NSR groups. No significant differences were observed between the NSR and HC groups.

Conclusion

The studied parameters can be used to assess change in disease status in NS patients. Data were consistent with NS being associated with expansion of ECW.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1511-y) contains supplementary material, which is available to authorized users.

Electrical Changes in Polish Patients with Chronic Heart Failure: Preliminary Observations

Introduction: Direct parameters resistance (R), reactance (Xc), phase angle (PA), capacitance of membrane (Cm), and impedance ratio (Z200/Z5)) determined by bioelectrical impedance analysis (BIA) detect changes in tissue electrical properties and have been found to be a marker of cell membrane function in various diseases. Materials and Method: The cross-sectional study was conducted to investigate whether direct bioimpedance parameters differ in a group of heart failure (HF) patients divided on the basis of the New York Heart Association (NYHA) functional classes I–II and III–IV. BIA was evaluated in 100 patients with HF treated in Clinic of Cardiology and Internal Medicine, Department of Cardiology, Military Hospital, Lublin. Results: In men, lower PA values (p = 0.01), Xc (p < 0.01), Cm (p = 0.02), and higher values of the Z200/Z5 ratio (p < 0.01) were observed in patients classified into NYHA groups III and IV in comparison to those with lower stages of disease. Similar correlations were noted in women (only Cm differences were insignificant). In addition, in men, C-Reactive Protein (CRP) correlated negatively with PA (p < 0.01), Xc (p < 0.01), and Cm (p < 0.01) and positively with the Z200/Z5 index (p < 0.01). There were no similar correlations observed in women. Conclusion: Patients with advanced CHF have altered electrical values. Changes in electrical values may directly reflect tissues as well as the whole-body condition.

Assessment of body water distribution in patients with sepsis during fluid resuscitation using multi-frequency direct segmental bioelectrical impedance analysis

BACKGROUND & AIMS

Although initial fluid resuscitation in sepsis is critical for the treatment of tissue hypoperfusion, little evidence supports the distribution of infused fluid in patients with sepsis. This study was designed to assess the body water distribution in patients with sepsis using bioelectrical impedance analysis and correlate the trend in body water distribution during fluid treatment with the prognosis of patients with sepsis.

METHODS

A prospective study in a single emergency department was performed, and adult patients suspected of having sepsis were enrolled. Multi-frequency direct segmental bioelectrical impedance analysis (InBody S10, InBody) measuring total body water (TBW), intracellular water (ICW), and extracellular water (ECW) was applied to patients with sepsis at three periods: before, immediately after, and 1 hour after the fluid treatment. Survival data at 28 days after the fluid treatment were obtained.

RESULTS

Forty-two patients were enrolled in this study. Overall, the ratios of TBW, ICW, and ECW to body weight increased throughout the fluid treatment except the ratio of ICW to body weight at 1 hour in non-survivors. While the ratio of ECW to TBW (ECW/TBW) and the ratio of ICW to TBW (ICW/TBW) in survivors remained stable over the period, the trend of ECW/TBW increased with corresponding decline of ICW/TBW in non-survivors (p = 0.0085 and p = 0.0034 between times and groups, respectively) such that ECW/TBW and ICW/TBW were significantly different at 1 hour after the fluid loading period (p = 0.0120 and p = 0.0085, respectively). This contrast pattern was equivalent with the trend of ECW/TBW in trunk but not that of the other extremities.

CONCLUSIONS

During fluid resuscitation, the trend in ECW/TBW significantly increased with corresponding decrease of ICW/TBW in non-survivors compared with that in survivors, which suggests fluid resuscitation results intracellular dehydration and extracellular edema in non-survivors of patients with sepsis.

Phase Angle: A Possible Biomarker to Quantify Inflammation in Subjects with Obesity and 25(OH)D Deficiency

Obesity is associated to chronic low-grade metabolic inflammation and hypovitaminosis D. Among extra-skeletal effects, an important role in inflammation has been described for vitamin D (25(OH)D). Phase angle (PhA) is a bioelectrical impedance analysis (BIA) parameter that represents an indicator of cellular health in chronic inflammatory states. However, it is still unknown whether a low 25(OH)D levels might correlate with PhA in obesity. Considering the lack of evidence correlating the 25(OH)D levels with PhA in obesity, the aim of this study was to investigate their possible relationship in a group of patients with obesity stratified according to body mass index (BMI) categories. Four hundred and fifty-five adult subjects (219 males and 236 females; 36 ± 11 years) were enrolled. Body composition, including PhA, was assessed using a BIA phase-sensitive system. Serum levels of 25(OH)D was determined by a direct competitive chemiluminescence immunoassay. Most of the participants were affected by grade III obesity (24%) and had 25(OH)D deficiency (67%). Subjects with 25(OH)D deficiency had highest BMI (p < 0.001). Stratifying the sample population according to the BMI classes, 25(OH)D levels decreased significantly along with the increase in BMI (p < 0.001), with the lowest 25(OH)D levels in the class III obesity. In addition, stratifying the sample population according to 25(OH)D categories, BMI and fat mass (FM) decreased, while PhA increased significantly along with the 25(OH)D categories (p < 0.001). The 25(OH)D levels showed significant positive associations with PhA (r = -0.59, p < 0.001), and this association remained significant also after adjusting for BMI and FM (r = 0.60, p < 0.001). The lowest values of PhA were significantly associated with the severity of obesity (OR 0.3, p < 0.001) and of 25(OH)D deficiency (OR 0.2, p < 0.001). To compare the relative predictive power of body composition parameters associated with the 25(OH)D levels, we performed a multiple linear regression analysis. The most sensitive and specific cut-off for 25(OH)D levels to predict the PhA above the median was >14 ng/mL (p < 0.001). In conclusion, we provided preliminary insights into a novel link between 25(OH)D levels and PhA in the setting of obesity. This association uncovered a new potential usefulness of PhA as expression of cell membrane integrity and predictor of inflammation in low 25(OH)D status that might help in identifying high-risk patients with obesity who could benefit from careful 25(OH)D supplementation.

Assessment of bioelectrical phase angle as a predictor of nutritional status in patients with Crohn's disease: A cross sectional study

BACKGROUND & AIMS

The assessment of body composition (BC) can be used to identify malnutrition in patients with Crohn's disease (CD). The aim of this study was to evaluate the nutritional status of CD patients by assessing BC, phase angle (PhA) and muscle strength. Differences in disease duration and medications were also considered.

METHODS

Consecutive adult CD patients aged 18-65 years were enrolled in this cross-sectional study. Disease activity was clinically defined by the Crohn's Disease Activity Index (CDAI) in the active and quiescent phases. All participants underwent anthropometry, BC and handgrip-strength (HGS) measurements; additionally, blood samples were taken. Data from CD patients were also compared with age-, sex- and BMI-matched healthy people.

RESULTS

A total of 140 CD patients with a mean age of 38.8 ± 13.9 years and a mean body weight of 64.9 ± 12 kg were recruited and compared to controls. The findings showed that all nutritional parameters, especially PhA and HGS, were lower in CD patients than in controls, and these parameters were substantially impaired as disease activity increased. Active CD patients had a lower body weight and fat mass than both the quiescent and control groups. PhA was negatively correlated with age (r = -0.362; p = 0.000) and CDAI (r = -0.135; p = 0.001) but was positively associated with fat free mass (FFM) (r = 0.443; p = 0.000) and HGS (r = 0.539; p = 0.000). Similarly, serum protein markers were lower in the active CD group than in the quiescent group (p < 0.05). Disease duration and medications did not significantly affect nutritional status.

CONCLUSIONS

BIA-derived PhA is a valid indicator of nutritional status in CD patients, and its values decreased with increasing disease activity. Additionally, small alterations in BC, such as low FFM, and reduced HGS values can be considered markers of nutritional deficiency. Therefore, the assessment of BC should be recommended in clinical practice for screening and monitoring the nutritional status of CD patients.

Análisis de la composición corporal mediante impedancia bioeléctrica octopolar en pacientes hospitalizados en Bogotá D.C., Colombia. Estudio piloto

Introducción. El uso de métodos confiables contribuye a diagnosticar de forma precisa el estado nutricional de individuos hospitalizados y, de esta manera, orientar el tratamiento nutricional.Objetivo. Describir la composición corporal mediante impedancia bioeléctrica (BIA) octopolar en pacientes hospitalizados en el Hospital Universitario Clínica San Rafael de Bogotá D.C., Colombia.Materiales y métodos. Estudio piloto de corte transversal. Se obtuvo información sociodemográfica, clínica y antropométrica. La composición corporal fue determinada con equipo portátil de BIA tipo SECA mBCA 514. La información fue analizada a través de medidas de tendencia central y dispersión, y frecuencias absolutas y relativas.Resultados. Se incluyeron 44 pacientes del servicio de hospitalización. Según el índice de masa corporal, hubo mayor proporción de pacientes con preobesidad (46.5%). En el grupo de mujeres se observó mayor cantidad de masa grasa y porcentaje de grasa estadísticamente significativa (p<0.028), a diferencia de la masa grasa visceral que fue significativamente mayor en los hombres (p<0.000). El ángulo de fase fue mayor en hombres que en mujeres (media 5.4° vs. 4.9°).Conclusión. El contenido de la masa músculoesquelética estuvo por debajo de los valores de referencia, lo cual se podría relacionar con desenlaces clínicos no favorables como aumento en la estancia hospitalaria y desarrollo de complicaciones, tanto infecciosas como no infecciosas.

Bioelectrical Impedance Analysis for Prediction of Early Complications after Gastrectomy in Elderly Patients with Gastric Cancer: the Phase Angle Measured Using Bioelectrical Impedance Analysis

Purpose

Phase angle obtained using bioelectrical impedance analysis (BIA) provides a relatively precise assessment of the nutritional status of elderly patients. This study aimed to evaluate the significance of phase angle as a risk factor for complications after gastrectomy in elderly patients.

Materials and Methods

We evaluated 210 elderly patients (aged ≥65 years) who had undergone gastrectomy for gastric cancer between August 2016 and August 2017. The phase angle cutoff value was calculated using receiver operating characteristic curve analysis according to sex. A retrospective analysis regarding the correlation between early postoperative complications and well-known risk factors, including the phase angle, was performed.

Results

Multivariate analysis revealed that the presence of two or more comorbidities (odds ratio [OR], 3.675) and hypoalbuminemia (OR, 4.059) were independent risk factors for overall complications, and female sex (OR, 2.993) was independent risk factor for severe complications. A low phase angle (OR, 2.901 and 4.348, respectively) and total gastrectomy (OR, 4.718 and 3.473, respectively) were independent risk factors for both overall and severe complications.

Conclusions

Our findings show that preoperative low phase angle predicts the risk of overall and severe complications. Our findings suggest that BIA should be performed to assess the risk of postoperative complications in elderly patients with gastric cancer.

Low Bioelectrical Impedance Phase Angle Is a Significant Risk Factor for Frailty

The phase angle, which is measured via bioelectrical impedance analysis (BIA), is a clinically important bioimpedance parameter used for nutritional assessment and evaluating the risk of various diseases, such as locomotive syndrome (LS). It remains unclear if the phase angle is associated with frailty (fragile state of physical and mental health). We therefore examined this association in a large prospective sample. Of 1081 individuals receiving health checkups, 550 (male; 235, female; 365) were enrolled in this study. We applied the Japanese version of the Cardiovascular Health Study criteria to evaluate frailty and administered the 25-Item Geriatric Locomotive Function Scale to diagnose LS. The phase angle was measured via BIA. Multiple logistic regression analysis was used to evaluate the relationship between the phase angle and frailty. For all participants and for each sex, the phase angle was significantly lower among individuals with frailty. After controlling for age, sex, and body mass index, we found that a low phase angle was a significant risk factor of frailty. As a result of multiple regression analysis including other confounding factors, among male participants, a low phase angle was significantly related with both frailty (P = 0.015) and LS (P < 0.001), whereas among female participants, the low phase angle had a stronger association with frailty (P = 0.001) than with LS (P = 0.52). Our findings suggest that a low angle is a risk factor of frailty. Furthermore, among female participants, frailty has a stronger relation with the phase angle than does LS. Therefore, the phase angle may be considered a useful indicator of frailty that does not require lengthy or costly assessment.

Assessment of Body Composition in Health and Disease Using Bioelectrical Impedance Analysis (BIA) and Dual Energy X-Ray Absorptiometry (DXA): A Critical Overview

The measurement of body composition (BC) represents a valuable tool to assess nutritional status in health and disease. The most used methods to evaluate BC in the clinical practice are based on bicompartment models and measure, directly or indirectly, fat mass (FM) and fat-free mass (FFM). Bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) (nowadays considered as the reference technique in clinical practice) are extensively used in epidemiological (mainly BIA) and clinical (mainly DXA) settings to evaluate BC. DXA is primarily used for the measurements of bone mineral content (BMC) and density to assess bone health and diagnose osteoporosis in defined anatomical regions (femur and spine). However, total body DXA scans are used to derive a three-compartment BC model, including BMC, FM, and FFM. Both these methods feature some limitations: the accuracy of BIA measurements is reduced when specific predictive equations and standardized measurement protocols are not utilized whereas the limitations of DXA are the safety of repeated measurements (no more than two body scans per year are currently advised), cost, and technical expertise. This review aims to provide useful insights mostly into the use of BC methods in prevention and clinical practice (ambulatory or bedridden patients). We believe that it will stimulate a discussion on the topic and reinvigorate the crucial role of BC evaluation in diagnostic and clinical investigation protocols.

Malnutrition predicts long-term survival in hospitalized patients with gastroenterological and hepatological diseases

BACKGROUND & AIMS

Malnutrition is a common problem in hospitalized patients, influencing treatment outcomes, length of hospital stay, quality of life and overall survival. However, the association of nutritional status parameters with long-term mortality has not yet been studied systematically in gastroenterological-hepatological patients. The present study aimed to assess the association between nutritional status parameters as characterized by Nutritional Risk Screening (NRS), anthropometry, serum transferrin, bioelectrical impedance analysis (BIA) and long-term overall survival in hospitalized gastroenterological-hepatological patients.

METHODS

Nutritional status was assessed in 644 gastroenterological-hepatological patients by NRS score. In addition, body mass index (BMI) and serum transferrin were determined and BIA was performed. Mid-upper arm circumference (MUAC) and triceps skinfold thickness (TST) were measured. Patients were followed for a mean period of 67 months (mean 54.8, range 0-107 months).

RESULTS

During malnutrition screening, 475 (73.8%) patients were diagnosed as sufficiently nourished by NRS (NRS 0-2), while an increased risk of malnutrition was found in 169 (26.2%) patients (NRS≤3). Malnutrition was significantly associated with less favourable results for BMI (p < 0.001), serum transferrin (p < 0.001), BIA (p < 0.001), MUAC (p < 0.001) and TST (p < 0.05). Overall 5-year survival rates (YSR) were much shorter in malnourished patients whether with (5-YSR: 43.9%) or without (73.6%) malignancy. Overall 5-year survival rates (YSR) were much shorter in malnourished patients whether with (5-YSR: 43.9%) or without (73.6%) malignancy. By the multivariable analysis the NRS ≥3 and, phase angle (PhA) over the 5th percentile or over the mean of the cohort were found to be associated with long-term survival.

CONCLUSIONS

Malnutrition is highly prevalent in hospitalized gastroenterological-hepatological patients and is associated with distinct clinical diagnoses. In the present study we demonstrated that malnutrition characterized by the NRS, anthropometry, serum transferrin and BIA, not only predicts short-term but also significantly poor long-term outcome in these patients.

Low Phase Angle Is Correlated With Worse General Condition in Patients with Advanced Cancer

OBJECTIVES

Phase angle (PA) is a poor prognostic factor in patients with advanced cancer. This study aimed to identify possible correlations between PA and symptoms, quality of life, fluid retention, and laboratory data in cancer patients in palliative care settings.

METHODS

Individuals who visited the outpatient clinic or were admitted to the palliative care unit were eligible. Patients with a performance status of 4 and/or those unable to complete questionnaires were excluded. PA was evaluated using a bioanalyzer device. The correlation coefficient between PA and the variables of interest was analyzed.

RESULTS

A total of 102 patients were analyzed. PA was weakly correlated with age (ρ = -0.22), performance status (ρ = -0.30), functional well-being (ρ = 0.20), anorexia/cachexia subscale (ρ = 0.22), and Functional Assessment of Anorexia/Cachexia Therapy trial outcome index (ρ = 0.26). PA was also correlated with fluid retention (ρ = -0.34) and albumin (ρ = 0.32), C-reactive protein (ρ = -0.31), and hemoglobin (ρ = 0.41) levels. Sub-analysis stratified according to sex revealed that males demonstrated the same results; however, female sex demonstrated a correlation between PA and social well-being (ρ = -0.43).

CONCLUSIONS

PA was correlated with physical condition, but not with psychological well-being.

Feeding tube transparietal thickness - A promising anthropometric parameter for nutritional assessment of endoscopic gastrostomy fed patients

BACKGROUND & AIMS

Malnutrition is common in patients eligible for percutaneous endoscopic gastrostomy (PEG). Feeding tube transparietal thickness (TT) may contribute to assess nutritional status. This study aims to: 1) Characterize TT in PEG patients. 2) Determine the association between TT and the currently used tools 3) Define TT best cut-offs to predict undernutrition 4) Assess the correlation between TT and survival.

METHODS

Prospective cohort study including patients who underwent PEG. Nutritional assessment was performed using NRS 2002, anthropometry and serum proteins. Anthropometry included body-mass index (BMI), mid upper arm circumference (MUAC), triceps skinfold (TSF) and mid arm muscle circumference (MAMC). TT was measured immediately after PEG and survival was recorded. TT cut-offs were established by comparison with other anthropometric parameters and using the ROC analysis. The correlation between TT and survival was assessed.

RESULTS

227 patients (161 men and 66 women) aged 23-96 years. Most presented head or neck cancer (51.1%). Undernutrition was identified in 57.7% according with BMI. Median TT was 25 mm (IQR = 10). TT was correlated with BMI (R = 0.5), MUAC (R = 0.5), TSF (R = 0.5) and MAMC (R = 0.4) (p < 0.01), respectively, being accurate in predicting undernutrition (AUROC 0.71 ± 0.033, p < 0.01). TT <20 mm showed positive predictive value of 81.6% and specificity of 84.4% to detect undernutrition. TT was correlated with survival (R = 0.1) (p = 0.05). Head or neck cancer patients' survival was significantly lower if TT ≤ 25 mm (p = 0.03).

CONCLUSIONS

TT is variable among PEG patients but values below 20-25 mm are suggestive of undernutrition. TT defined in the day of the gastrostomy procedure is the easiest anthropometric parameter that can be obtained from a PEG patient. Due to its higher positive predictive value and correlation with survival, TT should be viewed as an additional anthropometric tool specific for PEG patients, with diagnostic and prognostic value.

ESPEN guideline on clinical nutrition in liver disease

This update of evidence-based guidelines (GL) aims to translate current evidence and expert opinion into recommendations for multidisciplinary teams responsible for the optimal nutritional and metabolic management of adult patients with liver disease. The GL was commissioned and financially supported by ESPEN. Members of the guideline group were selected by ESPEN. We searched for meta-analyses, systematic reviews and single clinical trials based on clinical questions according to the PICO format. The evidence was evaluated and used to develop clinical recommendations implementing the SIGN method. A total of 85 recommendations were made for the nutritional and metabolic management of patients with acute liver failure, severe alcoholic steatohepatitis, non-alcoholic fatty liver disease, liver cirrhosis, liver surgery and transplantation as well as nutrition associated liver injury distinct from fatty liver disease. The recommendations are preceded by statements covering current knowledge of the underlying pathophysiology and pathobiochemistry as well as pertinent methods for the assessment of nutritional status and body composition.

Nutritional Intervention in Chronic Liver Failure

Patients suffering from chronic liver failure (CLF) frequently are malnourished and do not achieve an adequate intake of nutrients, in particular protein. Low protein intake and loss of muscle mass and function, termed sarcopenia, are indicators of a poor outcome. CLF patients, therefore, should be screened for risk of malnutrition using a validated tool, and if positive, full assessment of nutritional status is mandatory including search for sarcopenia. The main goal of nutritional intervention is to provide enough protein (1.2–1.5 g × kg^–1 × day^–1) and to ensure adequate energy intake (total energy 30 kcal × kg^–1 × day^–1; 1.3 × resting energy expenditure). Livers of CLF patients are deplete in glycogen and, therefore, prolonged periods of fasting (&#x3e;12 h) must be avoided in order to prevent further breakdown of muscle protein for gluconeogenesis. Therefore, late evening snacks or even nocturnal oral nutritional supplements improve total body ­protein status and thus, are recommended. Nutrition intervention should be stepped up from nutrition counselling to oral nutritional supplements, to enteral tube feeding, or to parenteral nutrition as appropriate. As in other malnourished patients, the prevention of refeeding syndrome or vitamin/trace element deficiency should be taken care of.

Decreased Bioelectrical Impedance Phase Angle in Hospitalized Children and Adolescents with Newly Diagnosed Type 1 Diabetes: A Case-Control Study

The aim of this study was to assess the body composition and nutritional status of hospitalized pediatric patients with newly diagnosed type 1 diabetes by using bioelectrical impedance analysis (BIA) with phase angle (PA) calculation. PA is considered to be a useful and very sensitive indicator of the nutritional and functional status, and it has not yet been evaluated in such a population. Sixty-three pediatric patients aged 4 to 18 years, with newly diagnosed type 1 diabetes, were included in the study. The control group consisted of 63 healthy children and adolescents strictly matched by gender and age in a 1:1 case: control manner. In both groups, BIA with PA calculation was performed. Diabetic patients, in comparison to control subjects, had a highly significantly lower PA of 4.85 ± 0.86 vs. 5.62 ± 0.81, p < 0.001. They also demonstrated a lower percentage of body cell mass (BCM%), 46.89 ± 5.67% vs. 51.40 ± 4.19%, p < 0.001; a lower body cell mass index (BCMI), 6.57 ± 1.80% vs. 7.37 ± 1.72%, p = 0.004; and a lower percentage of muscle mass (MM%), 44.61 ± 6.58% vs. 49.40 ± 7.59%, p < 0.001, compared to non-diabetic controls. The significantly lower PA value in diabetic patients indicate their worse nutritional and functional status compared to healthy subjects. To assess the predictive and prognostic value of this finding in this population, further prospective studies involving larger sample of patients are required.

Representative body composition percentiles from bioelectrical impedance analyses among children and adolescents. The MoMo study

BACKGROUND & AIMS

With high prevalence of overweight and obesity in developed countries, the assessment of body composition in children and adolescents is of growing interest. The aim of this study was (i) to provide up-to-date population wide percentiles for meaningful diagnostic bioelectrical impedance outcome parameters and (ii) to specify reference values for these measures in a normal weight subpopulation.

METHODS

A representative nationwide sample of 4 to 24-year-old children and adolescents (n = 3593) was drawn out of 167 primary sample points across Germany from 2009 to 2012 (Motorik-Modul study wave 1). Fat free mass index (FFMI), fat mass index (FMI), body cell mass index (BCMI) and phase angle (PA) were derived from four electrodes 50 kHz bioelectrical impedance analyses. Sex-specific percentiles were calculated using the LMS-method for the total study population and a normal weight subsample (defined according to the international BMI-standard by Cole).

RESULTS

Percentile curves for body composition parameters are similar between boys and girls until puberty. Subsequently, girls show a higher FMI than boys, and boys increase their FFM, BCM, and PA time-shifted, in that order. Differences in FMI between the overall and the normal weight sample increase with age, showing an age-dependent prevalence for overweight and obesity among the representative German sample.

CONCLUSIONS

Results from the normal weight sample can be used as reference values to define a healthy body composition. Differences in body composition between the representative German sample and the normal weight subsample reveal a high prevalence of elevated fat mass in the population of children and adolescents living in Germany.