Bioelectrical impedance phase angle in clinical practice: implications for prognosis in stage IIIB and IV non-small cell lung cancer

A new label free spiral sensor using impedance spectroscopy to characterize hepatocellular carcinoma in tissue and serum samples

Hepatocellular carcinoma (HCC) stands as the most prevalent form of primary liver cancer, predominantly affecting patients with chronic liver diseases such as hepatitis B or C-induced cirrhosis. Diagnosis typically involves blood tests (assessing liver functions and HCC biomarkers), imaging procedures such as Computed Tomography (CT) and Magnetic Resonance Imaging (MRI), and liver biopsies requiring the removal of liver tissue for laboratory analysis. However, these diagnostic methods either entail lengthy lab processes, require expensive imaging equipment, or involve invasive techniques like liver biopsies. Hence, there exists a crucial need for rapid, cost-effective, and noninvasive techniques to characterize HCC, whether in serum or tissue samples. In this study, we developed a spiral sensor implemented on a printed circuit board (PCB) technology that utilizes impedance spectroscopy and applied it to 24 tissues and sera samples as proof of concept. This newly devised circuit has successfully characterized HCC and normal tissue and serum samples. Utilizing the distinct dielectric properties between HCC cells and serum samples versus the normal samples across a specific frequency range, the differentiation between normal and HCC samples is achieved. Moreover, the sensor effectively characterizes two HCC grades and distinguishes cirrhotic/non-cirrhotic samples from tissue specimens. In addition, the sensor distinguishes cirrhotic/non-cirrhotic samples from serum specimens. This pioneering study introduces Electrical Impedance Spectroscopy (EIS) spiral sensor for diagnosing HCC and liver cirrhosis in clinical serum-an innovative, low-cost, rapid (< 2 min), and precise PCB-based technology without elaborate sample preparation, offering a novel non-labeled screening approach for disease staging and liver conditions.

Association of Phase Angle Dynamics with Sarcopenia and Activities of Daily Living in Osteoporotic Fracture Patients

BACKGROUND

This study aimed to determine whether changes in phase angle during rehabilitation are associated with clinical outcomes such as activities of daily living (ADL), skeletal muscle mass index (SMI), and strength in patients with osteoporotic fractures.

METHODS

This retrospective observational study included patients with osteoporotic fractures admitted to convalescent rehabilitation wards. Changes in phase angle were defined as the difference between the phase angle values at discharge and on admission. The primary outcome was the Functional Independence Measure motor (FIM-motor) score at discharge. The secondary outcomes were SMI and handgrip strength at discharge. We used multivariate analysis to adjust for confounding factors and examine the association between changes in the phase angle and outcomes.

RESULTS

We analyzed a total of 115 patients (97 women, mean age of 81.0±10.0 years), with a median change in phase angle of 0° during hospitalization. We observed increased phase angles in 49 patients (43%), with a median increase of 0.2°. Multiple regression analysis showed that changes in phase angle were independently associated with FIM-motor score at discharge (β=0.238, p=0.027). Changes in phase angle were not significantly associated with SMI (β=0.059, p=0.599) or handgrip strength (β=-0.032, p=0.773) at discharge.

CONCLUSION

An increased phase angle during rehabilitation was positively associated with ADL improvement in patients with osteoporotic fractures. These findings may help clinicians make informed decisions regarding patient care and treatment strategies for better outcomes.

Bioelectrical impedance analysis-derived phase angle (PhA) in lung cancer patients: a systematic review

BACKGROUND

Lung cancer is the second most diagnosed cancer in the world. Up to 84% of diagnosed patients have malnutrition, which can negatively affect quality of life and survival and may worsen with neoadjuvant treatment. Bioelectrical Impedance Analysis-Derived Phase Angle (PhA) in these patients could be a valid tool to assess the nutritional status in order to improve their condition.

METHODS

This review provides an update on PhA assessment in lung cancer patients over the past twenty years. We searched PubMed, Embase, Scopus, Web of Science, and Cochrane, for articles regarding the PhA obtained from Bioelectrical Impedance Analysis in lung cancer patients. The authors independently performed a literature search: sample size, patient population, study type, study dates, survival and interventions were evaluated. The final review included 11 studies from different countries.

RESULTS

Eight studies only considered patients with lung cancer, while three studies considered patients with different kind of cancer, including lung. Correlation data between PhA and age are conflicting. In patients undergoing clinical treatment and patients undergoing surgical treatment lower PhA was observed. A lower PhA is associated with a shorter survival. In three studies emerged a relationship between Karnofski Performance Status and Handgrip Strenght with PhA. From one study, univariate logistic regression analysis showed that higher PhA values represent a protective factor for sarcopenia.

CONCLUSION

Our research underlined interesting, but not conclusive, results on this topic; however more researches are needed to understand the clinical meaning of PhA.

Nutritional and Body Composition Changes in Paediatric β-Thalassemia Patients Undergoing Hematopoietic Stem Cell Transplantation: A Retrospective Study Using Bioelectrical Impedance Analysis

Objective

This retrospective study evaluated nutritional status and body composition changes in paediatric β-thalassemia (β-TM) patients before and after hematopoietic stem cell transplantation (HSCT), using bioelectrical impedance analysis (BIA), and explored their relationship with HSCT outcomes.

Methods

A cohort of 40 paediatric β-TM patients undergoing allogeneic HSCT was assessed for their nutritional status, anthropometric parameters, including body mass index (BMI), weight, and height, and body composition parameters pre-and post-HSCT, focusing on BIA measurements, including intracellular water (ICW), extracellular water (ECW), fat mass (FAT), fat-free mass (FFM), Skeletal Muscle Mass (SMM), soft Lean Mass (SLM), percent body fat (PBF), Body Cell Mass (BCM), Phase angle (PA) and muscle balance pre- and post-HSCT. Post-HSCT clinical outcomes, including acute graft-vs-host disease (aGVHD), engraftment time, oral mucositis (OM), sinusoidal obstruction syndrome (SOS), and diarrhoea in relation to nutrition status after HSCT were analysed.

Results

After HSCT, 28.21% experienced diminished nutritional status, with 71.43% of those who were wasting before HSCT showing diminished nutritional status, significantly higher than the normal group (18.75%, P = 0.012). Anthropometric changes included significant weight reduction (87.5%, 22.15 ± 7.46 vs 20.74 ± 6.57, P < 0.001) and BMI decrease (90%, 15.19 ± 1.70 vs 14.05 ± 1.48, P < 0.001). Body composition parameters, which are FFM, SMM, SLM, ICW, ECW, BCM, and PA (18.26 ± 5.71 vs 17.27 ± 5.19, 8.68 ± 3.30 vs 7.93 ± 3.02, 17.11 ± 5.28 vs 16.06 ± 4.84, 8.19 ± 2.54 vs 7.62 ± 2.31, 5.15 ± 1.58 vs 4.94 ± 1.47, 11.74 ± 3.63 vs 10.92 ± 3.32, 4.42 ± 0.50 vs 3.90 ± 0.57, respectively, P < 0.001) analysis revealed significant decreases. No significant differences in clinical outcomes were observed based on nutritional status.

Conclusion

Paediatric β-TM patients undergoing HSCT exhibit significant changes in nutrition status and body composition, emphasizing the need for focused attention on malnourished children who are more prone to diminished nutritional status. Comprehensive BIA aids in understanding the impact, urging consideration for extended follow-up and larger cohorts in future research.

Glycated hemoglobin (HbA1c) is independently associated with the bioelectrical impedance phase angle in junior sumo wrestlers: A pilot study

The study explores the relationship between phase angle (PhA), an indicator of cellular health, and metabolic health parameters among junior sumo wrestlers in Japan. Given the demanding lifestyle and high-energy diets of sumo wrestlers that predispose them to metabolic syndrome post-retirement, this study focuses on a younger cohort. The primary aim is to evaluate if PhA could serve as an early indicator of metabolic health issues within this unique demographic. A total of 14 sumo wrestlers aged 9-17 years were assessed to determine the relationship between PhA and various metabolic markers, including glycated hemoglobin (HbA1c), using a TANITA MC-780A-N body composition analyzer and standard blood tests. Bivariate regression analysis and Pearson's correlation revealed a negative relationship between PhA and HbA1c even after adjusting for age and weight (ß = -0.496, r2 = 0.776, r = -0.756, p = 0.004). The results indicate a significant negative relationship between PhA and HbA1c levels, suggesting that lower PhA values, which indicate poorer cellular integrity, are associated with higher HbA1c levels, signifying impaired glycemic control. These findings underscore the potential of PhA as a valuable biomarker for monitoring metabolic health in young sumo wrestlers, with implications for early intervention and management strategies.

Maximal Running Speed and Critical Speed Are Positively Related to Phase Angle in Healthy Young Adults

Phase Angle (PhA), derived from bioelectrical impedance analysis, is a measurement of cellular resistance to electrical current and a non-invasive tool to monitor neuromuscular performance. The relationship between PhA and components of athletic performance is not fully understood. The purpose of this study was to determine if maximal running speed, critical speed (CS), and/or D prime (D') derived from a 3-minute all-out-test (3MAOT) correlates to PhA, reactance (Xc), or resistance (R). Sixty-one (male n=35, female n=26) healthy young adults (23.4±3.9 years) completed bioelectrical impedance analysis (Inbody770) and a 3MAOT. The correlations between PhA, Xc, and R and 3MAOT results were evaluated using correlations. Simple and multiple linear-regressions were used to test if results from the 3MAOT (maximum running speed, CS, D') could predict PhA. Linear regression analysis indicated that maximum running speed and CS alone explained 32% and 9% of the variance in PhA, respectively (R2=0.32, p<0.05; R2=0.09, p<0.05). Multiple linear regression indicated that maximum running speed, CS, and D' explained 35% of the variance in PhA (R2=0.35; p<0.05). Only maximum running speed remained a significant predictor of PhA after controlling for age (β=0.45; p<0.05), but not after controlling for both age and sex (β=0.14; p>0.05). Since maximum running speed was a stronger predictor of PhA compared to CS (proxy for endurance performance), practitioners should use discernment when using PhA as a readiness tool to monitor endurance performance.

Bioelectrical Impedance Analysis (BIA) for the Assessment of Body Composition in Oncology: A Scoping Review

Bioelectrical Impedance Analysis (BIA) is a reliable, non-invasive, objective, and cost-effective body composition assessment method, with high reproducibility. This scoping review aims to evaluate the current scientific and clinical evidence on BIA for body composition assessment in oncology patients, under active treatment. Literature search was conducted through MEDLINE, CINAHL, Scopus and Web of Science databases, following PRISMA-ScR Guidelines. Inclusion criteria comprised studies reporting the use of BIA for body composition evaluation in adults with cancer diagnosis. Studies including non-cancer pathology or only assessing nutritional status were excluded. This scoping review comprised a total of 36 studies: 25 were original studies including 18 prospective studies, six cross-sectional studies and one retrospective study and 11 were systematic reviews. Population size for the included original articles ranged from 18 to 1217 participants, comprising a total of 3015 patients with cancer with a mean baseline Body Mass Index (BMI) ranging from 20.3 to 30.0 kg/m2 and mean age ranging between 47 and 70 years. Review articles included a total of 273 studies, with a total of 78,350 participants. The current review considered studies reporting patients with head and neck cancer (HNC) (n = 8), breast cancer (BC) (n = 4), esophageal cancer (EC) (n = 2), liver cancer (n = 2), pancreatic cancer (PC) (n = 3), gastric cancer (GC) (n = 3), colorectal cancer (CRC) (n = 8), lung cancer (LC) (n = 1), skin cancer (SK) (n = 1) and multiple cancer types (n = 6). BIA is a suitable and valid method for the assessment of body composition in oncology. BIA-derived measures have shown good potential and relevant clinical value in preoperative risk evaluation, in the reduction of postoperative complications and hospital stay and as an important prognostic indicator in persons with cancer. Future research on the diagnostic value and clinical applications of BIA and BIA-derived phase angle (PhA) should be conducted in order to predict its impact on patient survival and other clinical outcomes.

Prognostic role of body composition in peritoneal carcinomatosis patients undergoing cytoreduction and hyperthermic intraperitoneal chemotherapy

BACKGROUND

Bioelectric impedance analysis (BIA)-measured body composition and nutritional status have been used as prognostic indicators in various cancer cohorts. This study investigated whether BIA could provide information on prognosis in peritoneal carcinomatosis patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

We retrospectively analyzed the data of 99 patients with preoperative BIA data among those who underwent CRS and HIPEC. The association between BIA-derived parameters and intraoperative peritoneal cancer index (PCI) score was assessed. Predictive analysis for the occurrence of postoperative morbidities including major complications (Clavien-Dindo classification 3-4) and re-admission within 30 days after surgery as well as 1 year mortality was also performed.

RESULTS

BIA-derived mineral (r = 0.224, p = 0.027), fat (r =  - 0.202, p = 0.048), and total body water (TBW)/fat-free mass (FFM) (r =  - 0.280, p = 0.005) showed significant associations with intraoperative PCI score. Lower TBW/FFM was an independent predictor of major postoperative complications (OR 0.047, 95% CI 0.003-0.749, p = 0.031) and re-admission (OR 0.094, 95% CI 0.014-0.657, p = 0.017) within 30 days after surgery. Higher fat mass was also independently associated with a higher risk of major postoperative complications (OR 1.120, 95% CI 1.006-1.248, p = 0.039) and re-admission (OR 1.123, 95% CI 1.024-1.230, p = 0.013). Intraoperative PCI score > 20 (OR 4.489, 95% CI 1.191-16.917, p = 0.027) and re-admission within 30 days after surgery (OR 5.269, 95% CI 1.288-21.547, p = 0.021) independently predicted postoperative 1-year mortality.

CONCLUSIONS

We demonstrate that preoperative BIA-derived TBW/FFM and fat mass were significantly correlated with metastatic extent, assessed by PCI score, in patients with peritoneal carcinomatosis. In addition, BIA-derived TBW/FFM and fat mass showed independent predictability for postoperative 30-day major complications and re-admission in patients undergoing CRS and HIPEC. Our findings suggest that assessment of BIA may improve discrete risk stratification in patients who are planned to receive CRS and HIPEC.

Association between the phase angle and muscle-tendon complex function in Japanese athletes: a comparative study

[Purpose] In this study, we investigated the association between the phase angle and the muscle-tendon complex in Japanese athletes and the effects of aging on this association. [Participants and Methods] The study included 61 adult male high school soccer players. Body composition was evaluated using an analyzer, and grip strength and rebound jump index were measured to evaluate muscle-tendon complex function. Study participants were categorized into two groups, and statistical analyses were performed for intergroup comparison of outcomes and to determine the correlation between the phase angle and muscle-tendon complex function. [Results] We observed significant intergroup differences in the phase angle, total body muscle mass, grip strength, and rebound jump index. Additionally, we observed a significant positive correlation between the phase angle and grip strength in adult soccer players. [Conclusion] Our results showed a correlation between the phase angle and muscle-tendon complex function in mature adult athletes but not in high school athletes. These findings suggest that the phase angle may serve as an indicator of muscle quality and overall physical condition in adult athletes. Further research is warranted to investigate the association between the phase angle and other performance measures to gain a better understanding of soccer players' athletic abilities.

Determinants of phase angle in Japanese patients with diabetes

Phase angle, obtained using bioelectrical impedance analysis, non-invasively reflects the whole-body cellular condition and nutritional status and may be helpful as a prognostic factor. Patients with diabetes had a smaller phase angle than healthy subjects. However, the clinical significance of phase angle has not yet been elucidated. Therefore, the purpose of this study was to clarify the relationship between phase angle and HbA1c in patients with diabetes and the clinical relevance of phase angle. A retrospective, multicenter, cross-sectional study was conducted with Japanese patients with diabetes. Body composition was determined with bioelectrical impedance analysis, and this was used to obtain phase angle. Phase angle was assessed in relation to clinical parameters, body composition parameters, and HbA1c levels. A total of 655 patients were enrolled (400 men and 255 women, aged 57.1 ± 14.8 years, body mass index 25.6 ± 5.2 kg/m2, HbA1c 8.1 ± 1.9%). Even in patients with diabetes, the phase angle was higher in men than in women and did not differ between the types of diabetes. Multiple regression analysis, performed with phase angle as the objective variable, and age, sex, diabetes type, HbA1c, albumin level, and body mass index as explanatory variables, revealed that phase angle was negatively affected by HbA1c (B = - 0.043, 95% Confidence interval: - 0.07 to - 0.02, p < 0.001). HbA1c, age, sex, albumin level, and body mass index were independent determinants of phase angle in participants with diabetes.

Phase angle as a marker of outcome in hospitalized pediatric patients. A systematic review of the evidence (GRADE) with meta-analysis

Phase angle (PhA) is a valuable tool for evaluating the nutritional and inflammatory status, which can accompany acute and severe disorders. PhA is a cellular health biomarker, whose value is particularly substantial due to the negative consequences of these situations in the pediatric population. Relevant literature was collected with the aim of comprehensively analysing the evidence on the association between an altered PhA can serve as a predictive-marker for mortality and poor-outcomes in at-risk-pediatric patients. Understanding this relationship could have significant implications for identifying high-risk individuals and implementing timely interventions. A systematic review with meta-analysis was conducted in the primary electronic databases from inception until January 2023. Overall, four studies with a total of 740 patients were eligible for our analysis. Evidence demonstrates that PhA is associated with nutritional status, reflecting undernutrition and changes in body composition related to illness. This review suggests that PhA can indeed be used as an indicator of nutritional status and a tool for predicting prognosis, including mortality and poor-outcomes, in hospitalized pediatric patients. A low PhA was associated with a significant mortality risk [RR:1.51;95%CI (1.22-1.88),p = 0.0002;I2 = 0%,(p = 0.99)] and an increased complications risk [OR:8.17;95%CI (2.44-27.4),p = 0.0007;I2 = 44%,(p = 0.18)]. These findings highlight the importance of taking a comprehensive approach to clinical nutrition, integrating multiple evaluation aspects to establish an accurate diagnosis and personalized therapeutic plans. While PhA emerges as a valuable tool for assessing the risk of malnutrition and as a prognostic-indicator for poor-outcomes in pediatric patients. Further future studies are needed to focus on investigating this relationship in larger and diverse population to strengthen the evidence base.

Association of indirect measurement of cell function by bioimpedance analysis with complications in oncologic hepatic surgery

BACKGROUND

Bioelectric impedance vector analysis (BIVA) is a reliable tool to assess body composition. The aim was to study the association of BIVA-derived phase angle (PA) and standardized PA (SPA) values and the occurrence of surgery-related morbidity.

METHODS

Patients undergoing hepatectomy for cancer in two Italian centers were prospectively enrolled. BIVA was performed the morning of surgery. Patients were then stratified for the occurrence or not of postoperative morbidity.

RESULTS

Out of 190 enrolled patients, 76 (40%) experienced postoperative complications. Patients with morbidity had a significant lower PA, SPA, body cell mass, and skeletal muscle mass, and higher extracellular water and fat mass. At the multivariate analysis, presence of cirrhosis (OR 7.145, 95% CI:2.712-18.822, p < 0.001), the Charlson comorbidity index (OR 1.236, 95% CI: 1.009-1.515, p = 0.041), the duration of surgery (OR 1.004, 95% CI:1.001-1.008, p = 0.018), blood loss (OR 1.002. 95% CI: 1.001-1.004, p = 0.004), dehydration (OR 10.182, 95% CI: 1.244-83.314, p = 0.030) and SPA < -1.65 (OR 3.954, 95% CI: 1.699-9.202, p = 0.001) were significantly and independently associated with the risk of complications.

CONCLUSION

Introducing BIVA before hepatic resections may add valuable and independent information on the risk of morbidity.

The phase angle as a predictor of postoperative complications in patients undergoing lung cancer surgery

PURPOSE

The phase angle (PhA), calculated by bioelectrical impedance analysis, is used as a nutritional risk indicator. A low preoperative PhA has been reported as a marker of postoperative complications in patients with cancer; however, the relationship between the PhA and postoperative complications in patients with lung cancer remains unknown. We conducted this study to assess the predictive ability of the preoperative PhA for postoperative complications in patients undergoing surgery for primary lung cancer.

METHODS

We reviewed the data on 240 patients who underwent surgery for primary lung cancer at our institution between August, 2019 and August, 2021.

RESULTS

The PhA value in this study was 4.7 ± 0.7°. According to the Clavien-Dindo classification, grade ≥ II postoperative complications occurred in 53 patients (22.0%). Based on the multivariate logistic analysis, only the PhA (odds ratio, 0.51, 95% confidence interval, 0.29-0.90, p = 0.018) was an independent predictor of Clavien-Dindo grade ≥ II postoperative complications.

CONCLUSIONS

The PhA may be a valuable marker for predicting the risk of postoperative complications following lung cancer surgery.

Phase angle, muscle tissue, and resistance training

The biophysical response of the human body to electric current is widely appreciated as a barometer of fluid distribution and cell function. From distinct raw bioelectrical impedance (BIA) variables assessed in the field of body composition, phase angle (PhA) has been repeatedly indicated as a functional marker of the cell's health and mass. Although resistance training (RT) programs have demonstrated to be effective to improve PhA, with varying degrees of change depending on other raw BIA variables, there is still limited research explaining the biological mechanisms behind these changes. Here, we aim to provide the rationale for the responsiveness of PhA determinants to RT, as well as to summarize all available evidence addressing the effect of varied RT programs on PhA of different age groups. Available data led us to conclude that RT modulates the cell volume by increasing the levels of intracellular glycogen and water, thus triggering structural and functional changes in different cell organelles. These alterations lead, respectively, to shifts in the resistive path of the electric current (resistance, R) and capacitive properties of the human body (reactance, Xc), which ultimately impact PhA, considering that it is the angular transformation of the ratio between Xc and R. Evidence drawn from experimental research suggests that RT is highly effective for enhancing PhA, especially when adopting high-intensity, volume, and duration RT programs combining other types of exercise. Still, additional research exploring the effects of RT on whole-body and regional BIA variables of alternative population groups is recommended for further knowledge development.

Phase angle in assessment and monitoring treatment of individuals with respiratory disease

Phase angle (PhA) represents a raw variable measured with bioelectrical impedance analysis (BIA) that is used to assess malnutrition in many diseases, including respiratory diseases, mainly chronic obstructive pulmonary disease (COPD). COPD patients with reduced PhA are older, more hypoxic and hypercapnic; patients with more severe COPD have reduced cell mass, evident skeletal muscle depletion, and worsening gas exchange. Malnourished patients with stable COPD in long-term oxygen therapy (LTOT) have more intense dyspnea at rest, greater weight loss over the past 12 months, and more exacerbations per year. Multiple regression analysis highlighted the significance of PhA° in the estimation of muscle strength: hand grip strength (HGS) and in that of respiratory muscles: maximal inspiratory pressure / max. expiratory pressure ratio (MIP/MEP). Furthermore, the relationship between PhA° and all-cause mortality in COPD patients was confirmed with the Cox regression model, Kaplan-Meier test, and log-rank tests. The role of malnutrition in idiopathic pulmonary fibrosis (IPF) is confirmed by the PhA° measurements which, regardless of body weight, is associated with the reduction in muscle mass of these patients, reduces their strength and exercise capacity, and greatly influences the prognosis. In conclusion PhA is a novel biomarker of morbidity and mortality in patients with severe respiratory diseases.

Association of Phase Angle with Overall Survival in Patients with Cancer: A Prospective Multicenter Cohort Study

Low phase angle (PhA) is related with poor clinical status of cancer patients. The objective of this study was to establish sex- and age-specific cutoff points and examine the association between PhA and overall survival (OS) in Chinese cancer patients. This cohort study included data on 1,814 patients with cancer from December 2013 to October 2020. The association between low PhA and overall survival was analyzed using the Kaplan-Meier method and Cox regression model. Among 1,814 participants, there were 993 (54.70%) male and 821 (45.30%) female patients. The optimal cutoff points of low PhA were 4.8°, 4.2°, 4.4°, and 3.8° for the young male, elderly male, young female, and elderly female, respectively. Low PhA was independently associated with poorer OS in young female, elderly female and male (HR: 1.59, 95% CI: 1.08-2.34; HR: 1.65, 95% CI: 1.03-2.67; HR: 2.00, 95% CI: 1.45-2.75). In addition, low PhA was demonstrated to be an adverse prognostic factor in patients with lung cancer, colorectal cancer, and esophagus cancer (HR: 1.85, 95% CI: 1.39-2.47; HR: 2.05, 95% CI: 1.13-3.70; HR: 2.92, 95% CI: 1.49-5.71). Based on cutoff points, low PhA was associated with worse prognosis in patients with cancer.

Sex differences in the association of phase angle and lung cancer mortality

Background

Lung cancer is a lethal malignant tumor that is common worldwide and is associated with a high incidence of malnutrition. Phase angle (PA) is a simple, objective, and non-invasive indicator of body composition that has increasingly attracted attention as an indicator of the nutritional status and prognosis of patients with malignant tumors. This study aimed to investigate the association between the PA and overall survival in patients with lung cancer.

Methods

This study prospectively analyzed 804 lung cancer patients in the Investigation on Nutrition Status and its Clinical Outcome of Common Cancers (INSCOC) project from 40 hospitals in China. We used a restricted cubic spline to analyze the sex-specific association between PA and mortality in men and women with lung cancer. Cox regression analysis was used to evaluate the independent association between PA and mortality in men and women. Sensitivity analysis was performed. The Kaplan-Meier method was used to evaluate the survival of patients with high and low PA values.

Results

There was an L-shaped association between PA and survival in both men and women with lung cancer (p = 0.019 and p = 0.121, respectively). Kaplan-Meier survival analysis suggested that patients with a high PA showed a better survival than patients with a low PA (p = 0.007 for men and p < 0.001 for women). Multivariate-adjusted Cox regression analysis showed that PA was an independent risk factor for mortality in men (HR = 0.79, 95% CI = 0.65-0.95, p = 0.015), but not in women (HR = 0.83, 95% CI = 0.67-1.04, p = 0.105).

Conclusion

Phase angle is an independent risk factor for the mortality of male lung cancer patients. However, its role in predicting the mortality of female lung cancer patients seems to be limited.

Phase angle (PhA) in overweight and obesity: evidence of applicability from diagnosis to weight changes in obesity treatment

Phase angle (PhA) is a recently proposed marker of nutritional status in many clinical conditions. Its use in patients with obesity presents different critical concerns due to the higher variability of the two measured parameters (resistance, R, and reactance, Xc) that contribute to the determination of PhA. Controversial is the relation between PhA and BMI that might vary with graded levels of obesity due to the variation in fat and free fat mass. Obesity is frequently associated with metabolic, hepatic, cardiovascular and kidney diseases that introduce variations in PhA values, in relation to multimorbidity and severity degree of these diseases. It is reported that the improvement of clinical condition is associated with a positive change in PhA. Also, the treatment of obesity with weight loss might confirm this effect, but with different responses in relation to the type and duration of the intervention applied. In fact, the effect appears not only related to the percentage of weight loss but also the possible loss of free fat mass and the nutritional, metabolic and structural modifications that might follow each therapeutic approach to decrease body weight. We can conclude that the PhA could be used as marker of health status in patients with obesity supporting an appropriate weight loss intervention to monitor efficacy and fat free mass preservation.

Phase angle and standardized phase angle from bioelectrical impedance measurements as a prognostic factor for mortality at 90 days in patients with COVID-19: A longitudinal cohort study

BACKGROUND & AIMS

Severe acute COVID-19 has taken on pandemic proportions with growing interest in identification of prognostic factors for mortality. Standardized bioelectrical impedance (BI) phase angle (SPhA), which is PhA adjusted by age and sex, has been related to mortality in patients with several diseases but never investigated in COVID-19. Inflammation, a consequence of COVID-19 infection, affects fluid status (hydration) and can be identified with PhA. The aim of this study was to determine the predictive role of PhA on 90 days survival of adults with COVID-19.

METHODS

We studied 127 consecutive patients diagnosed with COVID-19. BI measurements determined with a 50 kHz phase-sensitive BI device, body composition parameters and laboratory markers were evaluated as predictors of mortality.

RESULTS

Non-surviving COVID-19 patients had significantly lower PhA and SPhA values (p < 0.001) and increased hydration (p < 0.001) compared to surviving patients. Patients in the lowest SPhA quartile had increased (p < 0.001) mortality and hospital stay, hyperhydration (p < 0.001), increased inflammation biomarkers [CRP (p < 0.001)], decreased nutritional parameters: body mass cell index [BCMI (p < 0.001) albumin (p < 0.001)], and reduced other biomarkers [D-dimer (p = 0.002)]. Multivariate analysis (Cox regression) revealed that PhA and hydration status, adjusted for age, sex, BMI, diabetes, hypertension, dyslipidaemia or heart disease, were associated (p < 0.001) with increased mortality. The hazard ratio was 2.48 (95% CI, 1.60-3.84, p < 0.001) for PhA and 1.12 (95% CI, 1.04-1.20, p = 0.003) for hydration percentage. PhA <3.95° was the cut-off for predicting mortality in acute COVID-19 with 93.8% sensitivity and 66.7% specificity. PhA offers greater sensitivity as a predictive prognostic test at admission, compared to the established analytical parameters of poor prognosis (CRP, lymphocytes, prealbumin).

CONCLUSIONS

Low PhA (<3.95°), independent of age, sex, BMI, and comorbidities, is a significant predictor of mortality risk in COVID-19. These findings suggest that the evaluation of body composition with single-frequency phase-sensitive BI measurements should be included in the routine clinical assessment of COVID-19 patients at hospital admission to identify patients at increased mortality risk.

Exploring the Relationship between Obesity, Metabolic Syndrome and Neuroendocrine Neoplasms

Obesity is a major burden for modern medicine, with many links to negative health outcomes, including the increased incidence of certain cancer types. Interestingly, some studies have supported the concept of an “Obesity Paradox”, where some cancer patients living with obesity have been shown to have a better prognosis than non-obese patients. Neuroendocrine neoplasms (NENs) are malignancies originating from neuroendocrine cells, in some cases retaining important functional properties with consequences for metabolism and nutritional status. In this review, we summarize the existing evidence demonstrating that obesity is both a risk factor for developing NENs as well as a good prognostic factor. We further identify the limitations of existing studies and further avenues of research that will be necessary to optimize the metabolic and nutritional status of patients living with NENs to ensure improved outcomes.

Phase Angle as a Predictor for Physical Function in Institutionalized Independent Older Adults

The aim of this study was to investigate the relationship between phase angle (PhA) and physical function in institutionalized, independent older adults. Physical function was evaluated using the Senior Fitness Test Battery. PhA was measured by electrical bioimpedance at 50 khz, and body composition parameters were also registered. Results showed that PhA significantly correlated with all physical fitness tests, except for arm curls. Regarding the results of the multivariate analysis, three models were created: Model 1, formed by a dependent variable "PhA" and two predictor variables "8 ft up-and-go" and "6 min walk"; Model 2, formed by a dependent variable "PhA" and three predictor variables "8 ft up-and-go", "6 min walk" and "30-s chair stand"; and Model 3, formed by a dependent variable "PhA" and four predictor variables "8 ft up-and-go", "6 min walk", "30-s chair stand" and "arm curl". Results showed that predictor variables had a significant influence on the PhA for all three models (Model 1: p = 0.001, 12.5%; Model 2: p = 0.002, 12.9%; and Model 3: p = 0.005, 13.1%). For women, Model 1 showed a significant influence of predictor variables on the PhA (p = 0.030, 9.3%). The results for men in Models 1, 2 and 3 showed significant influences on the PhA (p = 0.002, 31.2%; p = 0.006, 31.6%; and p = 0.016, 31.6%; respectively). This study confirmed previous studies regarding to the relationship between PhA and physical function. It also indicates that PhA could be an excellent predictor of physical function.

Phase angle obtained via bioelectrical impedance analysis and objectively measured physical activity or exercise habits

The phase angle (PhA), measured via bioelectrical impedance analysis, is considered an indicator of cellular health, where higher values reflect higher cellularity, cell membrane integrity, and better cell function. This study aimed to examine the relationship between PhA and exercise habits or objectively measured physical activity. We included 115 people aged 32-69 years. The body composition and PhA were measured using a bioelectrical impedance device. Physical activity and sedentary behavior (SB) were assessed using a triaxial accelerometer. Exercise habits were also obtained through structured interviews, and participants were categorized into the no exercise habit (No-Ex), resistance training exercise habit (RT), or aerobic training exercise habit (AT) groups. Objectively measured moderate-to-vigorous physical activity or step count significantly correlated with PhA, independent of age, sex, height, percent body fat, body cell mass, and leg muscle power. In contrast, SB was not significant determinants of PhA. People who exercised regularly (RT or AT) had significantly higher PhA values than did those in the No-Ex group. Furthermore, the PhA was not significantly different between the RT and AT groups. Regularly engaging in exercise with moderate-to-vigorous intensity may improve or maintain muscle cellular health and muscle quality.

Phase Angle, a Cornerstone of Outcome in Head and Neck Cancer

In patients with head and neck cancer, malnutrition is common. Most cases are treated by chemo-radiotherapy and surgery, with adverse effects on the aerodigestive area. Clinical and biochemical characteristics, health-related quality of life, survival, and risk of death were studied. The selected subjects were divided into normal- and low-phase-angle (PA) groups and followed up for at least two years. Mean ages were 67.2 and 59.3 years for low and normal PA, respectively. Patients with PA < 4.42° had significant differences in age, anthropometric and biochemical indicators of malnutrition, and inflammatory status compared to patients with PA > 4.42°. Statistical differences were found in the functional and symptom scales, with lower functional scores and higher symptom scores in patients with low PA. Median survival was 19.8 months for those with PA < 4.42° versus 34.4 months for those with PA > 4.42° (p < 0.001).The relative risk of death was related to low PA (2.6; p < 0.001). The percentage of living patients (41.7%) is almost the same as the percentage of deceased subjects (43.1%; p = 0.002), with high death rates in patients with PA < 4.42°. Phase angle was the most crucial predictor of survival and a risk factor for death in the studied cases.

Assessment of changes in muscle mass, strength, and quality and activities of daily living in elderly stroke patients

Whether poststroke rehabilitation improves muscle mass and quality along with the recovery of muscle strength is not clear. In this study, we examined the changes in muscle strength, muscle mass, and muscle quality in patients undergoing poststroke rehabilitation and assessed the relationship of these variables with improvement in activities of daily living (ADL). This prospective study was conducted at stroke rehabilitation unit in Japan. Muscle mass and quality were assessed using bioelectrical impedance analysis (BIA). ADLs were assessed using the functional independence measure (FIM). Grip strength of the nonaffected and affected sides was measured using hand dynamometer. All measurements were performed at admission to the stroke rehabilitation unit and at 4 weeks thereafter. We assessed changes in motor FIM items and examined the relationships among the measured variables. This study included 179 patients. Patients received stroke rehabilitation 7 days a week individually. Muscle strength and quality significantly increased after 4 weeks on both the sides. Muscle mass decreased after 4 weeks; however, there was no significant difference between the two time points. Changes in muscle strength and quality showed a significant correlation with improvement in ADLs [r = 0.66 (male), 0.45 (female) and 0.55 (male), 0.31 (female), respectively]; however, muscle mass showed no correlation with improvement in ADLs. Poststroke rehabilitation improves muscle strength and quality, as well as ADLs. Muscle mass is not an appropriate measure to assess the effects of stroke rehabilitation; it is desirable to instead use muscle strength and quality to assess stroke rehabilitation.

Relationship between Nutritional Status, Body Composition, Muscle Strength, and Functional Recovery in Patients with Proximal Femur Fracture

Sarcopenia is a major issue among the elderly. However, the effects of nutritional status and body composition on functional recovery in patients with proximal femur fractures (PFF) remain unclear. Hence, this study aimed to investigate the effects of nutritional status, body composition (skeletal muscle mass and muscle quality measured by phase angle [PhA] values), and muscle strength on the improvement in activities of daily living (ADL) in patients with PFF. We enrolled patients with PFF admitted to a rehabilitation unit. Nutritional status, body composition, grip strength, and motor Functional Independence Measure (FIM) score were assessed on admission day and at 4 weeks thereafter. Of 148 patients, 84 had femoral neck fractures, and 64 had trochanteric fractures. The mean motor FIM score was 49.2 points at admission and 64.9 points after 4 weeks. In multivariate analysis, higher geriatric nutritional risk index and PhA measured by anthropometry were associated with a significantly higher FIM score after 4 weeks. Muscle strength and quality changes significantly correlated with ADL improvement. Poor nutritional status and decreased muscle strength and quality interfered with ADL recovery. Nutritional management before injury and from the acute phase, and rehabilitation to maintain skeletal muscle status, are important for ADL recovery.

Cancer, Phase Angle and Sarcopenia: The Role of Diet in Connection with Lung Cancer Prognosis

Lung cancer is the most common cause of cancer death and is associated with malnutrition and sarcopenia. The detection of sarcopenia and conduction of simple body composition measurements, such as the phase angle (PhA) deriving from bioelectrical impedance analysis (BIA), can help to early identify, monitor, prevent and treat malnutrition. The present review aims to clarify the relationship between PhA and sarcopenia with the pathophysiology, clinical outcomes, and therapeutic aspects of lung cancer. PhA and sarcopenia are connected to lung cancer prognosis through various mechanisms including inflammation and oxidative stress, although more research is needed to identify the critical thresholds for increased mortality risk. Moreover, emphasis is given on the role of dietary interventions (oral nutritional supplementation, and dietary counseling) to manage sarcopenia and related variables in patients with lung cancer. Oral nutritional supplements and/or those containing n - 3 polyunsaturated fatty acids may have a positive effect on physical strength measures and muscle mass if administered at the beginning of chemotherapy. Data on sole dietary counseling or multimodal interventions are less promising so far. In the future, sophisticated body composition phenotypes deriving from the described methods along with artificial intelligence techniques could be used to design personalized nutrition interventions and timely treat these patients.

A Low Body Fat Mass Ratio Predicts Poor Prognosis in Patients with Advanced Non-Small Cell Lung Cancer

PURPOSE

The aim of this study was to investigate the effect of the body fat mass ratio on survival and prognosis in advanced non-small-cell lung cancer patients.

METHODS

The study includes 200 patients who were diagnosed with advanced non-small-cell lung cancer between 2014 and 2018 and whose body fat mass percentage and body mass index (BMI) were determined using the Tanita Body Composition Analyzer during admission.

RESULTS

All patients had advanced incurable non-small-cell lung cancer (30% had locally advanced disease, 70% were stage IV). In the univariate and multivariate analyses, age, gender, histopathological type, smoking history, comorbidities, weight loss in the last six months and body mass index had no statistically significant effect on survival (p > 0.05). However, the performance status (p = 0.008), metastatic status (p = 0.003) and body fat mass ratio (p = 0.01) were found to have a significant effect on overall survival (OS): the median OS was 16.4 mo, in patients with the BFM ratio ≤ 22% and 29.2 mo, in those with > 22% (p = 0.01).

CONCLUSION

In this study, it was found that the body fat mass ratio was an important prognostic factor in patients with advanced non-small-cell lung cancer.

Prognostication of the last days of life: Review article

Accurate prediction of impending death (i.e., last few days of life) is essential for terminally-ill cancer patients and their families. International guidelines state that clinicians should identify patients with impending death, communicate the prognosis with patients and families, help them with their end-of-life decision-making, and provide sufficient symptom palliation. Over the past decade, several national and international studies have been conducted that systematically investigated signs and symptoms of impending death as well as how to communicate such a prognosis effectively with patients and families. In this article, we summarize the current evidence on prognostication and communication regarding the last days of life of patients with cancer, and future directions of clinical research.

Creatinine-to-cystatin C ratio estimates muscle mass correlating the markers of the patients with severe motor and intellectual disabilities

AIM

The creatinine-to-cystatin C ratio (CCR) has been acknowledged as a potential marker of muscle mass. The purpose of the present study was to evaluate the relationship between CCR and nutritional status in a bioelectrical impedance analysis (BIA) of patients with severe motor and intellectual disabilities (SMID).

METHODS

This study included 39 patients with SMID (17 males, 22 females) over 16 years of age were included retrospectively. CCR was calculated as serum creatinine (mg/dL)/cystatin C (mg/L) × 10. The BIA parameters such as the phase angle (PhA), fat free mass (FFM), appendicular skeletal muscle mass (ASM) and appendicular skeletal muscle mass index (ASMI) values were measured using BIA. Correlation analyses between CCR and the BIA parameters were conducted.

RESULTS

The mean CCR is 4.47 ± 1.34. Significant positive relationships between CCR and FFM, PhA, ASM, ASMI were identified (r = 0.3373, p = 0.0357. r = 0.4273, p = 0.0093. r = 0.5008, p = 0.0012. r = 0.4706, p = 0.0025 and r = 0.4751, p = 0.0022, respectively).

CONCLUSIONS

The study indicated that CCR in the patients with SMID is a useful parameter that allows for the muscle mass to be estimated easily and accurately. This means that evaluating CCR could be used as a simple and important screening tool for PhA, FFM and muscle mass.

Predictors of Mortality in Patients with Advanced Cancer-A Systematic Review and Meta-Analysis

To timely initiate advance care planning in patients with advanced cancer, physicians should identify patients with limited life expectancy. We aimed to identify predictors of mortality. To identify the relevant literature, we searched Embase, MEDLINE, Cochrane Central, Web of Science, and PubMed databases between January 2000-April 2020. Identified studies were assessed on risk-of-bias with a modified QUIPS tool. The main outcomes were predictors and prediction models of mortality within a period of 3-24 months. We included predictors that were studied in ≥2 cancer types in a meta-analysis using a fixed or random-effects model and summarized the discriminative ability of models. We included 68 studies (ranging from 42 to 66,112 patients), of which 24 were low risk-of-bias, and 39 were included in the meta-analysis. Using a fixed-effects model, the predictors of mortality were: the surprise question, performance status, cognitive impairment, (sub)cutaneous metastases, body mass index, comorbidity, serum albumin, and hemoglobin. Using a random-effects model, predictors were: disease stage IV (hazard ratio [HR] 7.58; 95% confidence interval [CI] 4.00-14.36), lung cancer (HR 2.51; 95% CI 1.24-5.06), ECOG performance status 1+ (HR 2.03; 95% CI 1.44-2.86) and 2+ (HR 4.06; 95% CI 2.36-6.98), age (HR 1.20; 95% CI 1.05-1.38), male sex (HR 1.24; 95% CI 1.14-1.36), and Charlson comorbidity score 3+ (HR 1.60; 95% CI 1.11-2.32). Thirteen studies reported on prediction models consisting of different sets of predictors with mostly moderate discriminative ability. To conclude, we identified reasonably accurate non-tumor specific predictors of mortality. Those predictors could guide in developing a more accurate prediction model and in selecting patients for advance care planning.

Nonthyroidal illness syndrome (NTIS) in severe COVID-19 patients: role of T3 on the Na/K pump gene expression and on hydroelectrolytic equilibrium

Background

Nonthyroidal Illness Syndrome (NTIS) can be detected in many critical illnesses. Recently, we demonstrated that this condition is frequently observed in COVID-19 patients too and it is correlated with the severity the disease. However, the exact mechanism through which thyroid hormones influence the course of COVID-19, as well as that of many other critical illnesses, is not clear yet and treatment with T4, T3 or a combination of both is still controversial. Aim of this study was to analyze body composition in COVID-19 patients in search of possible correlation with the thyroid function.

Methods and findings

We report here our experience performed in 74 critically ill COVID-19 patients hospitalized in the intensive care unit (ICU) of our University Hospital in Rome. In these patients, we evaluated the thyroid hormone function and body composition by Bioelectrical Impedance Analysis (BIA) during the acute phase of the disease at admission in the ICU. To examine the effects of thyroid function on BIA parameters we analyzed also 96 outpatients, affected by thyroid diseases in different functional conditions. We demonstrated that COVID-19 patients with low FT3 serum values exhibited increased values of the Total Body Water/Free Fat Mass (TBW/FFM) ratio. Patients with the lowest FT3 serum values had also the highest level of TBW/FFM ratio. This ratio is an indicator of the fraction of FFM as water and represents one of the best-known body-composition constants in mammals. We found an inverse correlation between FT3 serum values and this constant. Reduced FT3 serum values in COVID-19 patients were correlated with the increase in the total body water (TBW), the extracellular water (ECW) and the sodium/potassium exchangeable ratio (Na_e:K_e), and with the reduction of the intracellular water (ICW). No specific correlation was observed in thyroid patients at different functional conditions between any BIA parameters and FT3 serum values, except for the patient with myxedema, that showed a picture similar to that seen in COVID-19 patients with NTIS. Since the Na⁺/K⁺ pump is a well-known T3 target, we measured the mRNA expression levels of the two genes coding for the two major isoforms of this pump. We demonstrated that COVID-19 patients with NTIS had lower levels of mRNA of both genes in the peripheral blood mononuclear cells (PBMC)s obtained from our patients during the acute phase of the disease. In addition, we retrieved data from transcriptome analysis, performed on human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM)s treated with T3 and we demonstrated that in these cells T3 is able to stimulate the expression of these two genes in a dose-dependent manner.

Conclusions

In conclusion, we demonstrated that measurement of BIA parameters is a useful method to analyze water and salt retention in COVID-19 patients hospitalized in ICU and, in particular, in those that develop NTIS. Our results indicate that NTIS has peculiar similarities with myxedema seen in severe hypothyroid patients, albeit it occurs more rapidly. The Na⁺/K⁺ pump is a possible target of T3 action, involved in the pathogenesis of the anasarcatic condition observed in our COVID-19 patients with NTIS. Finally, measurement of BIA parameters may represent good endpoints to evaluate the benefit of future clinical interventional trials, based on the administration of T3 in patients with NTIS.

Phase Angle From Bioelectrical Impedance for the Assessment of Sarcopenia in Cirrhosis With or Without Ascites

BACKGROUND AND AIMS

Skeletal muscle index (SMI) from computed tomography (CT) reliably assesses sarcopenia, however, it is expensive and involves serial radiation exposure. Phase angle (PhA) from bioimpedance analysis (BIA) is a noninvasive, low cost, bedside nutritional tool used to monitor changes to nutritional interventions. We aimed to compare the performance of PhA with SMI to assess sarcopenia in cirrhosis.

METHODS

Ambispective cohort study. Consecutive patients with cirrhosis and available images from abdominal CT scan were included. Monofrequency BIA was performed within 2 weeks CT. Spearman's correlation, ROC curve, and survival analysis with Kaplan-Meier, Cox and competing-risk regression were performed.

RESULTS

136 patients were included with a mean age of 54.5 years (60% female). Most had decompensated disease (66%) with ascites in 47%, and a mean MELD of 14 ± 6. We found positive correlations between SMI and PhA (r = 0.58 , P < .001), irrespective of the presence of ascites. The AUROC of PhA-sarcopenia in all patients was 0.702; (0.748 in males,0.677 in females). The best cutoffs of PhA for diagnosing sarcopenia were ≤5.6° in males and ≤5.4° in females. SMI and PhA were significantly associated with survival in Kaplan-Meier curves. In multivariable analyses, SMI was outperformed by age and MELD, whereas PhA remained independently associated with mortality. Considering transplantation as a competing risk, regression analysis showed both SMI and PhA to be independent predictors of mortality (sHR:0.95 [0.90-0.99] and sHR:0.61 [0.42-0.88]).

CONCLUSION

PhA moderately correlates with SMI for the identification of sarcopenia in patients with cirrhosis. However, its prognostic accuracy is comparable to that of SMI, and it is not influenced by ascites.

The clinical and cost-effectiveness of supplemental parenteral nutrition in oncology

Background

Clinical guidelines recommend that parenteral nutrition (PN) is added to enteral nutrition (EN; supplemental parenteral nutrition (SPN)) in order to meet energy and protein needs in patients with cancer when EN alone is insufficient. However, although cancer-related malnutrition is common, there is poor awareness of the value of nutritional care, resulting in SPN being chronically underused.

Methods

We performed a targeted literature review and exploratory cost-utility analysis to gather evidence on the clinical effectiveness of SPN, and to estimate the potential cost-effectiveness of SPN versus EN alone in an example cancer setting.

Results

The literature review identified studies linking SPN with malnutrition markers, and studies linking malnutrition markers with clinical outcomes. SPN was linked to improvements in body mass index (BMI), fat-free mass, phase angle (PhA) and prealbumin. Of these markers, BMI and PhA were strong predictors of survival. By combining published data, we generated indirect estimates of the overall survival HR associated with SPN; these ranged from 0.80 to 0.99 (mode 0.87). In patients with Stage IV inoperable pancreatic cancer, the incremental cost-effectiveness ratio versus EN alone was estimated to be £41 350 or £91 501 depending on whether nursing and home delivery costs for EN and SPN were combined or provided separately.

Conclusion

Despite a lack of direct evidence, the results of the literature review demonstrate that SPN may provide important clinical and quality of life benefits to patients with cancer. The potential for any improvement in outcomes in the modelled patient population is very limited, so cost-effectiveness may be greater in patients with less severe disease and other types of cancer.

The Role of Nutritional Support in Malnourished Patients With Lung Cancer

This review aimed to aggregate and describe the available data about clinical nutrition in lung cancer and the role of the dietitian in multidisciplinary patient care. Scientific literature was searched in order to summarize key aspects related to clinical nutrition in lung cancer. This information can be used to arrange a proper nutritional therapy that can enhance patient treatment responses, prevent side-effects, shorten recovery time, improve prognosis and increase quality of life. An anti-inflammatory diet rich in antioxidants, immunomodulatory compounds, dietary fibre and an appropriate intake of protein can reduce the risk of initiation and progression of lung cancer, support the regeneration of tissues (also after surgery) and improve the nutritional status during the disease and after remission. A correct intake of nutrients is significant prior to disease occurrence and at every stage of treatment and recovery.

Molecular and physical technologies for monitoring fluid and electrolyte imbalance: A focus on cancer population

Several clinical examinations have shown the essential impact of monitoring (de)hydration (fluid and electrolyte imbalance) in cancer patients. There are multiple risk factors associated with (de)hydration, including aging, excessive or lack of fluid consumption in sports, alcohol consumption, hot weather, diabetes insipidus, vomiting, diarrhea, cancer, radiation, chemotherapy, and use of diuretics. Fluid and electrolyte imbalance mainly involves alterations in the levels of sodium, potassium, calcium, and magnesium in extracellular fluids. Hyponatremia is a common condition among individuals with cancer (62% of cases), along with hypokalemia (40%), hypophosphatemia (32%), hypomagnesemia (17%), hypocalcemia (12%), and hypernatremia (1-5%). Lack of hydration and monitoring of hydration status can lead to severe complications, such as nausea/vomiting, diarrhea, fatigue, seizures, cell swelling or shrinking, kidney failure, shock, coma, and even death. This article aims to review the current (de)hydration (fluid and electrolyte imbalance) monitoring technologies focusing on cancer. First, we discuss the physiological and pathophysiological implications of fluid and electrolyte imbalance in cancer patients. Second, we explore the different molecular and physical monitoring methods used to measure fluid and electrolyte imbalance and the measurement challenges in diverse populations. Hydration status is assessed in various indices; plasma, sweat, tear, saliva, urine, body mass, interstitial fluid, and skin-integration techniques have been extensively investigated. No unified (de)hydration (fluid and electrolyte imbalance) monitoring technology exists for different populations (including sports, elderly, children, and cancer). Establishing novel methods and technologies to facilitate and unify measurements of hydration status represents an excellent opportunity to develop impactful new approaches for patient care.

Is bioelectrical impedance vector analysis a good indicator of nutritional status in children and adolescents?

OBJECTIVE

The study objective is to propose bioelectrical impedance vector analysis (BIVA) ellipses for the population and investigate its use to assess nutritional status through the BMI/age ratio and the cardiovascular risk through waist circumference (WC).

DESIGN

Age, weight, height and WC were recorded, along with the values of resistance (R), reactance (Xc) and phase angle (PA) by impedance. Student's t test and ANOVA were applied to ascertain the significance between means and a specific programme was applied to investigate the significance between ellipses.

SETTING

Fortaleza, Brazil.

PARTICIPANTS

A total of 467 students from public schools participated in the study: 120 children and 347 adolescents were evaluated, with respective means of age, weight and height of 8·2 years, 27·6 kg and 1·29 m and 12·7 years, 48·6 kg and 1·53 m, respectively.

RESULTS

The mean values of R/H, Xc/H and PA were 569·0 and 424·7 Ohm/m, 59·1 and 50·4 Ohm/m, and 5·9º and 6·8º for children and adolescents, respectively. The mean vectors for R/H and Xc/H show significant differences between for both age ranges and are inversely proportional to the BMI/A. As for WC, individuals without cardiovascular risk had higher R/H and lower Xc/H, but Xc and R in participants without cardiovascular risk were greater than with cardiovascular risk.

CONCLUSIONS

It was possible to propose confidence and tolerance BIVA ellipses for children and adolescent's clinical evaluation. The method was also suitable to identify cardiovascular risk ellipses in these age groups, but it was not possible to draw nutritional classifications ellipses by BMI/age data.

The diagnostic value of phase angle, an integrative bioelectrical marker, for identifying individuals with dysmobility syndrome: the Korean Urban-Rural Elderly study

Low phase angle, a non-invasive bioimpedance marker, is associated with elevated odds of dysmobility syndrome and its components. Phase angle (estimated cutoffs: < 4.8° in men; < 4.5° in women) can be used to detect dysmobility syndrome in community-dwelling older adults as a simple, integrative screening tool.

INTRODUCTION

Dysmobility syndrome uses a score-based approach to predict fracture risk that incorporates the concepts of osteoporosis, sarcopenia, and obesity. Low phase angle (PhA), a simple, non-invasive bioelectrical impedance marker, was associated with low lean mass, high fat mass, and poor muscle function. We aimed to investigate the association between PhA and dysmobility syndrome, with the exploration of the diagnostic cutoffs.

METHODS

In a community-dwelling Korean older adult cohort, dysmobility syndrome was defined as the presence of ≥ 3 of the following components: osteoporosis, low lean mass, falls in the preceding year, low grip strength, high fat mass, and poor timed up and go performance.

RESULTS

Among the 1825 participants (mean age 71.6, women 66.7%), subjects were classified into sex-stratified PhA tertiles. The prevalence of dysmobility syndrome increased from the highest PhA tertile group to the lowest (15.50 to 2.45% in men; 33.41 to 12.25% in women, P for trend < 0.001). The mean PhA values decreased as the dysmobility score increased (5.33° to 4.65° in men; 4.76° to 4.39° in women, P for trend < 0.001). Low PhA (cutoff: < 4.8° in men; < 4.5° in women) was associated with twofold elevated odds of dysmobility syndrome after adjusting for age, sex, and conventional risk factors. Low PhA improved the identification of individuals with dysmobility syndrome when added to the conventional risk model (area under the curve, 0.73 to 0.75, P = 0.002).

CONCLUSION

Low PhA was associated with dysmobility syndrome and its components, independent of age, sex, body mass index, nutritional status, and inflammation.

Association of bioelectrical phase angle with aerobic capacity, complex gait ability and total fitness score in older adults

PURPOSE

This study aimed to examine the association between whole-body or segmental phase angle (PhA) based on bioelectrical impedance analysis (BIA) and aerobic capacity (endurance), complex gait ability, and total fitness age score (FAS).

METHODS

A total of 426 community-dwelling older adults (332 women and 94 men) aged 60 to 93 years participated in this study. PhA and appendicular skeletal mass index (ASMI) were obtained by an eight-electrode standing BIA. Aerobic capacity was assessed using the shuttle stamina walk test (SSTw); complex gait ability, using the timed-up-and-go test (TUG). FAS was obtained using the previously validated multi-dimensional equations based on 7-year longitudinal data. SSTw, TUG, and FAS were compared between the low PhA (<4.4° for women and <5.2° for men) and normal PhA groups. Pearson's correlation between PhA and SSTw, TUG, and FAS was determined. Multiple linear regression analysis was conducted using SSTw, TUG, and FAS as dependent variables. Age, sex, height, body mass index (BMI), ASMI, and PhA were entered into the linear model.

RESULTS

SSTw and TUG results and FAS were significantly lower in the low PhA group (P < 0.05). PhA was significantly correlated with SSTw, TUG, and FAS (P < 0.001), and leg PhA showed a stronger correlation than whole-body or arm PhA. PhA at 50 kHz had higher correlation coefficients with SSTw, TUG, or FAS compared with PhA at 5 or 250 kHz. Multiple regression analyses indicated that leg PhA at 50 kHz was a significant predictor of SSTw, TUG, and FAS, independent of age, sex, height, BMI, and ASMI.

CONCLUSION

Our results indicate that leg PhA is associated with multi-dimensional physical fitness in community-dwelling older adults. PhA is a highly informative biomarker of skeletal muscle and exercise physiology in clinical settings.

Phase Angle and Frailty Are Important Prognostic Factors in Critically Ill Medical Patients: A Prospective Cohort Study

OBJECTIVES

To investigate whether phase angle (PhA) measured by bioelectrical impedance analysis (BIA) and frailty are associated with the outcomes of critical illnesses.

DESIGN

A single-center prospective cohort study.

SETTING

Medical intensive care unit (ICU) in Seoul National University Hospital, Seoul, Republic of Korea.

PARTICIPANTS

97 patients who were admitted to the medical ICU.

MEASUREMENTS

On admission, PhA was measured by BIA, and frailty was assessed by the Korean Modified Barthel Index (KMBI) scoring system. Patients were classified according to PhA and KMBI scores, and their impact on the outcomes of critical illnesses was evaluated.

RESULTS

The patients' mean age was 62.4 ± 16.4 years, and 56 of the patients (57.7%) were men. Having a high PhA above 3.5 at the time of ICU admission was associated with lower in-hospital mortality (adjusted OR 0.42, p = .042), and a shorter duration of ICU stay (5.6 days vs. 9.8 days, p = .016) compared to those with a low PhA. Other indices measured by BIA were not significantly associated with outcomes of critical illnesses. Frailty (KMBI > 60) was associated with more mechanical ventilation days (2.3 days vs. 7.1 days; p = .018).

CONCLUSION

Both PhA and frailty are important prognostic factors predicting the outcomes of critical illnesses. Low PhA scores were associated with increased mortality and a longer duration of ICU stay, and frailty was associated with more mechanical ventilation days.

Nutritional Support in Lung Cancer Patients: The State of the Art

Lung cancer (LC) represents the most commonly diagnosed neoplasm worldwide for both sexes and is the leading cause of cancer mortality. Malnutrition is a comorbidity frequently found in neoplastic patients, but it remains often underestimated and thus undertreated. In this review, we aimed to investigate the incidence of malnutrition among LC patients according to different screening and assessment tools, to evaluate the impact of weight loss and body composition on survival, and to analyze the efficacy of different nutritional interventions in this setting. Although malnutrition, weight loss, and body composition changes can affect survival and other clinical outcomes in LC patients, the role of nutritional interventions is not yet strongly proven, and further studies are recommended. Nevertheless, screening, assessing, and eventually treating malnutrition in LC patients are strongly recommended, according to the most recent nutritional intervention guidelines for oncology patients.

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.

Phase Angle Evaluation of Lung Disease Patients and Its Relationship with Nutritional and Functional Parameters

BACKGROUND

This study aimed to determine the value of phase angle (PhA) in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH) and its association with nutritional and functional parameters.

METHODS

A cross-sectional study of 77 patients under follow-up at the pulmonary outpatient clinic of a public hospital. Anthropometric measurements and functional assessments of physical and pulmonary capacity were performed, and a regular physical activity questionnaire was administered.

RESULTS

The sample consisted of 38 patients with COPD (mean age, 63.8 ± 9.9 years; 68.4% female) and 39 patients with PH (mean age, 46.6 ± 14.4 years; 79.5% female). There was no difference in anthropometric measurements between patients with COPD and PH. Patients with COPD had mild to moderate limitations of pulmonary function, while patients with PH had only mild limitations (p < 0.01). Although the median distance covered in the 6-minute walk test (6MWT) was different between the COPD and PH groups (p < 0.05), it was considered adequate for these populations. Mean PhA was within the range considered adequate in patients with COPD (6.3°±1°) and PH (6.2°±0.8°) (p > 0.05). In the statistical analyses, although the correlations were weak, adequate PhA correlated with fat free mass index, 6MWT, disease staging, forced vital capacity, and forced expiratory volume in the first second.

CONCLUSION

The anthropometric profile of both patient groups was very similar, and PhA values were within the expected range. Despite weak correlations, PhA is a clinical component to be followed and investigated in patients with lung disease.

Phase angle associated with different indicators of health-related physical fitness in adults with obesity

In obese populations, the exacerbated increase in adipose tissue results in a significant reduction of health-related physical fitness and can affect the phase angle (PhA), a promising health indicator of cell health and integrity. The aim of this study was to investigate the association of PhA with health-related physical fitness indicators in obese adults. This cross-sectional study had a non-probabilistic sample and was conducted from April to June 2018. The PhA was obtained by a bioelectrical impedance analysis, and the health-related physical fitness indicators evaluated were percentage of body fat (%BF), lower- and upper-body maximal strength, cardiorespiratory fitness (relative V̇O2peak), and flexibility. Pearson and Spearman´s linear correlations, crude and adjusted linear regression analyses were performed. A total of 69 obese adults (60.8% female; BMI = 33.5 ± 2.8 kg/m²) with a mean age of 34.6 ± 7.1 years were studied. The PhA means were 5.8 (±0.6º) and had an inverse correlation with %BF (r=-0.74; p<0.001) and positive correlation with V̇O2peak (r=0.50; p<0.001), lower- and upper-body maximal strength (r=0.65; r=0.70; p<0.001, respectively). After adjustment, %BF (β=-0.065, adjusted R²=0.53; p<0.001), lower- and upper-body maximal strength (β=0.004; adjusted R²=0.46; p<0.001, and β=0.024; adjusted R²=0.50; p<0.001, respectively) were predictors of PhA. Our results suggest the favorable role of PhA as a clinically viable tool to screen and identify the physical fitness variables and functional status of obese adults.

Correlation of Body Composition and Nutritional Status with Functional Recovery in Stroke Rehabilitation Patients

Previous studies have suggested that the nutritional status after stroke is independently associated with long-term outcomes and that sarcopenia delays poststroke rehabilitation and worsens the prognosis. However, many stroke patients have a deteriorated nutritional status and a decreased muscle mass in the acute phase. This prospective study included 179 patients who were admitted to the stroke rehabilitation unit. We performed bioelectrical impedance analysis and determined the Geriatric Nutritional Risk Index (GNRI) to assess muscle mass and the nutritional status on admission. Furthermore, we analyzed the activities of daily living using the Functional Independence Measure (FIM) at the time of admission and four weeks later. Furthermore, we evaluated the change in motor FIM items and examined the relationship with the data. Multiple regression analysis revealed that a high muscle rate (skeletal muscle mass/body weight) (odds ratio OR = 2.43), high phase angle (OR = 3.32), and high GNRI (OR = 2.57) were significantly associated with motor FIM items at four weeks in male and female patients. Muscle mass maintenance through nutritional management and early rehabilitation in the acute period of stroke is essential for functional recovery in stroke patients.

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.

Impedance-Based Monitoring of Mesenchymal Stromal Cell Three-Dimensional Proliferation Using Aerosol Jet Printed Sensors: A Tissue Engineering Application

One of the main hurdles to improving scaffolds for regenerative medicine is the development of non-invasive methods to monitor cell proliferation within three-dimensional environments. Recently, an electrical impedance-based approach has been identified as promising for three-dimensional proliferation assays. A low-cost impedance-based solution, easily integrable with multi-well plates, is here presented. Sensors were developed using biocompatible carbon-based ink on foldable polyimide substrates by means of a novel aerosol jet printing technique. The setup was tested to monitor the proliferation of human mesenchymal stromal cells into previously validated gelatin-chitosan hybrid hydrogel scaffolds. Reliability of the methodology was assessed comparing variations of the electrical impedance parameters with the outcomes of enzymatic proliferation assay. Results obtained showed a magnitude increase and a phase angle decrease at 4 kHz (maximum of 2.5 kΩ and -9 degrees) and an exponential increase of the modeled resistance and capacitance components due to the cell proliferation (maximum of 1.5 kΩ and 200 nF). A statistically significant relationship with enzymatic assay outcomes could be detected for both phase angle and electric model parameters. Overall, these findings support the potentiality of this non-invasive approach for continuous monitoring of scaffold-based cultures, being also promising in the perspective of optimizing the scaffold-culture system.

Concurrent validity of an appetite questionnaire in peritoneal dialysis

BACKGROUND

Decreased appetite is a symptom often found in chronic kidney disease. Poor appetite may negatively affect food intake, what in long-term may contribute to the development of protein-energy malnutrition.

METHODS

An Appetite and Food Satisfaction Questionnaire (AFSQ) was developed consisting of a question that assesses the level of appetite through a facial hedonic scale and five other questions adapted from the Buckner and Dwyer tool that assess some aspects related to food satisfaction. Each question received an arbitrary score of 0 to 3. The sum of the scores ranged from 0, the best, to 18, the worst condition. Nutritional status was assessed through seven-point SGA, bioelectrical impedance, anthropometry, and handgrip strength (HGS).

RESULTS

Eighty-four patients on peritoneal dialysis (PD; 58.3% women, mean age 54.7 ± 14.2 years, and body mass index (BMI) of 26.0 ± 4.8 kg/m²) were evaluated. Median AFSQ score was 4.0 (1.0-6.8; median and IQ). Patients were divided into tertiles according to the AFSQ score. Comparing the third tertile (score ≥ 6) with the first tertile (score < 2), the prevalence of malnutrition was greater (32.1% vs. 6.7%, respectively, p = 0.005), HGS adequacy was lower (74.6% vs. 87.3%, p = 0.001), and body cell mass index (5.7% vs. 7.4%, p = 0.001) and lean BMI were lower (11% vs. 13.4%, p = 0.001) in the third tertile.

CONCLUSION

Poor appetite and food satisfaction determined by the questionnaire was related to worse nutritional markers, indicating AFSQ as a valid easy-to-use tool to be applied as an initial screening to identify PD patients with potential risk of malnutrition.

The prognostic value of standardized phase angle in adults with acute leukemia: A prospective study

Standardized phase angle (SPhA) is a tool used to estimate body composition and cell membrane integrity. Standardized phase angle has been shown to predict survival in solid malignancies and hematopoietic stem cell transplant patients. We investigated the predictive value of SPhA on 60-day mortality, overall survival (OS), and length of hospital stay (LHS) for adults with acute myelogenous and lymphoblastic leukemia (AML and ALL). Consecutive patients ≥18 years with newly diagnosed acute leukemia receiving intensive chemotherapy were enrolled. Phase angle measurements were taken on day 1 of therapy for all patients and on the day of nadir marrow for AML patients. Measurements were standardized by BMI, gender, and age to calculate the SPhA. The difference between SPhA at nadir bone marrow compared to day 1 of induction was used to calculate change in SPhA. A cutoff of 25th percentile was used to dichotomize baseline SPhA. Among 100 patients, 88% were AML, 56% were female, and mean age was 59 years. Though not statistically significant, OS by Kaplan-Meier analysis was shorter for those below the 25th percentile SPhA compared to those above (median OS: 11.0 months vs 19.5 months; P = .09). Lower baseline SPhA was associated with increased incidence of 60-day mortality in univariable (odds ratio [OR] = 5.25; 1.35, 20.44; P = .02) but not multivariable analysis (OR = 3.12; 0.67, 14.48; P = .15) adjusted for age, creatinine, and cytogenetics. Increased change in SPhA was associated with worse OS (hazard ratio = 1.15; 1.00,1.33; P = .05) in multivariable analysis. Standardized phase angle is a rapid, noninvasive, and objective measure that may be used to inform risk stratification.