Assessment of changes in blood volume during lower body negative pressure-induced hypovolemia using bioelectrical impedance analysis

BACKGROUND

Lower body negative Pressure (LBNP)-induced hypovolemia is simulating acute hemorrhage by sequestrating blood into lower extremities. Bioelectrical Impedance Analysis (BIA) is based on the electrical properties of biological tissues, as electrical current flows along highly conductive body tissues (such as blood). Changes in blood volume will lead to changes in bioimpedance. This study aims to study changes in upper (UL) and lower (LL) extremities bioimpedance during LBNP-induced hypovolemia.

METHODS

This was a prospective observational study of healthy volunteers who underwent gradual LBNP protocol which consisted of 3-minute intervals: at baseline, -15, -30, -45, -60 mmHg, then recovery phases at -30 mmHg and baseline. The UL&LL extremities bioimpedance were measured and recorded at each phase of LBNP and the percentage changes of bioimpedance from baseline were calculated and compared using student's t-test. A P-value of < 0.05 was considered significant. Correlation between relative changes in UL&LL bioimpedance and estimated blood loss (EBL) from LBNP was calculated using Pearson correlation.

RESULTS

26 healthy volunteers were enrolled. As LBNP-induced hypovolemia progressed, there were a significant increase in UL bioimpedance and a significant decrease in LL bioimpedance. During recovery phases (where blood was shifted from the legs to the body), there were a significant increase in LL bioimpedance and a reduction in UL bioimpedance. There were significant correlations between estimated blood loss from LBNP model with UL (R = 0.97) and LL bioimpedance (R = - 0.97).

CONCLUSION

During LBNP-induced hypovolemia, there were reciprocal changes in UL&LL bioimpedance. These changes reflected hemodynamic compensatory mechanisms to hypovolemia.

Quantitative analysis of the effect of docetaxel-induced edema on quality of life in patients with breast cancer and related factors: a prospective cohort study

BACKGROUND

Systemic edema is an adverse effect of docetaxel chemotherapy and causes distress to patients, including those receiving this agent for breast cancer. However, its characteristics and factors related to its effect on quality of life (QoL) have not been adequately investigated. In this study, we assessed systemic edema quantitatively, explored related factors, and evaluated QoL in patients receiving docetaxel for breast cancer.

METHODS

The study had a prospective cohort design and included 37 patients with no known history of swelling who were treated with docetaxel between September 2019 and April 2022. Patients were examined at the start, middle, and end of their course of treatment and 1 and 2 months later. Body water content, body mass, fat mass, and muscle mass were quantified using bioelectrical impedance analysis. Systemic edema was evaluated with reference to the Common Terminology Criteria for Adverse Events. The timing of development of systemic edema at any anatomical site that was grade 2 or worse was recorded. QoL was assessed using the Quality of Life-Anti Cancer Drug scale. Nutrition was evaluated using the Brief-type self-administered diet history questionnaire. Multivariable logistic regression analysis was performed to identify related factors. QoL was also compared between patients with edema and those without edema.

RESULTS

Systemic edema developed in 67% of the study participants and was most prevalent at the end of treatment. Body fat mass (adjusted odds ratio [aOR] 0.802, 95% confidence interval [CI] 0.651-0.988, p = 0.038), disease stage (aOR 3.279, 95% CI 0.493-21.793, p = 0.219), and history of alcohol consumption (aOR 0.141, 95% CI 0.013-1.521, p = 0.106) were identified as risk factors for docetaxel-induced edema. Participants who developed systemic edema experienced more physical, vital, and emotional distress 1 month after treatment than those who did not. There was no association between systemic edema and nutrition.

CONCLUSIONS

Systemic edema may develop after treatment with docetaxel and increase distress in patients with a high body fat mass. Patients at risk of systemic edema should be informed in advance about the potential frequency, location, and timing of its onset and encouraged to self-manage this condition.

Bioimpedance-assessed muscle wasting and its relation to nutritional intake during the first week of ICU: a pre-planned secondary analysis of Nutriti Study

BACKGROUND

Muscle mass evaluation in ICU is crucial since its loss is related with long term complications, including physical impairment. However, quantifying muscle wasting with available bedside tools (ultrasound and bioimpedance analysis) must be more primarily understood. Bioimpedance analysis (BIA) provides estimates of muscle mass and phase angle (PA). The primary aim of this study was to evaluate muscle mass changes with bioimpedance analysis during the first 7 days after ICU admission. Secondary aims searched for correlations between muscular loss and caloric and protein debt.

METHODS

Patients with an expected ICU-stay ≥ 72 h and the need for artificial nutritional support were evaluated for study inclusion. BIA evaluation of muscle mass and phase angle were performed at ICU admission and after 7 days. Considering the difference between ideal caloric and protein targets, with adequate nutritional macronutrients delivered, we calculated the caloric and protein debt. We analyzed the potential correlation between caloric and protein debt and changes in muscle mass and phase angle.

RESULTS

72 patients from September 1st to October 30th, 2019 and from August 1st to October 30th, 2021 were included in the final statistical analysis. Median age was 68 [59-77] years, mainly men (72%) admitted due to respiratory failure (25%), and requiring invasive mechanical ventilation for 7 [4-10] days. Median ICU stay was 8 [6-12] days. Bioimpedance data at ICU admission and after 7 days showed that MM and PA resulted significantly reduced after 7 days of critically illness, 34.3 kg vs 30.6 kg (p < 0.0001) and 4.90° vs 4.35° (p = 0.0004) respectively. Mean muscle loss was 3.84 ± 6.7 kg, accounting for 8.4% [1-14] MM reduction. Correlation between caloric debt (r = 0.14, p = 0.13) and protein debt (r = 0.18, p = 0.13) with change in MM was absent. Similarly, no correlation was found between caloric debt (r = -0.057, p = 0.631) and protein debt (r = -0.095, p = 0.424) with changes in PA.

CONCLUSIONS

bioimpedance analysis demonstrated that muscle mass and phase angle were significantly lower after 7 days in ICU. The total amount of calories and proteins does not correlate with changes in muscle mass and phase angle.

Age-dependent effect of vitamin D supplementation on musculoskeletal health in chronic spinal cord injury patients: A pilot study

OBJECTIVE

To determine the effect of vitamin D supplementation on changes in body composition associated with musculoskeletal health status in patients with chronic SCI and vitamin D deficiency as a response to age.

DESIGN

Prospective drug-intervention study.

SETTING

Department of rehabilitation medicine, Veterans Health Service Medical Center.

PARTICIPANTS

Seventeen patients with vitamin D insufficiency/deficiency (<30 ng/mL) and chronic SCI were divided into two groups: groups A <65 years (n = 8) and B ≥65 years of age (n = 9).

INTERVENTIONS

Both groups received 800 IU/day cholecalciferol for 12 weeks.

OUTCOME MEASURES

We used blood samples to evaluate metabolites related to vitamin D, testosterone (T), lipid profiles, and sex hormone-binding globulin (SHBG). Bioelectrical impedance analysis (BIA) was used to evaluate body composition.

RESULTS

Group A had significantly better baseline clinical characteristics for all BIA measurements. SHGB was significantly higher in Group B (P = 0.003) and albumin was significantly higher in Group A (P = 0.000). When comparing pre- to post-treatment, Group A showed a significant improvement in T (P = 0.042), total cholesterol (P = 0.035), and triglyceride (P = 0.025) levels, whereas Group B significantly increased vitamin D (P = 0.038) and protein mass (PM) (P = 0.034) levels.

CONCLUSION

This study suggested that addressing vitamin D deficiency in patients with SCI had different effects in young and older adults, with both groups showing positive changes in body composition. Particularly, the increase in PM on BIA measurements in elderly patients at high risk of sarcopenia was encouraging.

The role of bioimpedance analysis in overweight and obese patients with acute heart failure: a pilot study

AIMS

Residual congestion at the time of hospital discharge is an important readmission risk factor, and its detection with physical examination and usual diagnostic techniques have strong limitations in overweight and obese patients. New tools like bioelectrical impedance analysis (BIA) could help to determine when euvolaemia is reached. The aim of this study was to investigate the usefulness of BIA in management of heart failure (HF) in overweight and obese patients.

METHODS AND RESULTS

Our study is a single-centre, single-blind, randomized controlled trial that included 48 overweight and obese patients admitted for acute HF. The study population was randomized into two arms: BIA-guided group and standard care. Serum electrolytes, kidney function, and natriuretic peptides were followed up during their hospital stay and at 90 days after discharge. The primary endpoint was development of severe acute kidney injury (AKI) defined as an increase in serum creatinine by >0.5 mg/dL during hospitalization, and the main secondary endpoint was the reduction of N-terminal pro-brain natriuretic peptide (NT-proBNP) levels during hospitalization and within 90 days after discharge. The BIA-guided group showed a remarkable lower incidence of severe AKI, although no significant differences were found (41.4% vs. 16.7%; P = 0.057). The proportion of patients who achieved levels of NT-proBNP < 1000 pg/mL at 90 days was significantly higher in the BIA-guided group than in the standard group (58.8% vs. 25%; P = 0.049). No differences were observed in the incidence of adverse outcomes at 90 days.

CONCLUSIONS

Among overweight and obese patients with HF, BIA reduces NT-proBNP levels at 90 days compared with standard care. In addition, there is a trend towards lower incidence of AKI in the BIA-guided group. Although more studies are required, BIA could be a useful tool in decompensated HF management in overweight and obese patients.

Chronic kidney disease-related sarcopenia as a prognostic indicator in elderly haemodialysis patients

BACKGROUND

The mortality of dialysis patients greatly exceeds that of the general population and identifying predictive factors for mortality may provide opportunities for earlier intervention. This study assessed the influence of sarcopenia on mortality in patients on haemodialysis.

METHODS

This prospective, observational study enrolled 77 haemodialysis patients aged 60 years and over, of whom 33 (43%) were female, from two community dialysis centres. Baseline demographic and laboratory data were collected, and sarcopenia was diagnosed using grip strength, muscle mass by bioimpedance analysis (BIA) and muscle function by timed up-and-go according to European Working Group on Sarcopenia in Older People criteria. Nutritional status was assessed using a subjective nutritional assessment score, comprising functional changes in weight, appetite, gastrointestinal symptoms and energy.. A comorbidity score (maximum 7 points) was derived from the presence or absence of hypertension, ischaemic heart disease, vascular disease (cerebrovascular disease, peripheral vascular disease, and abdominal aortic aneurysm), diabetes mellitus, respiratory disease, a history of malignancy and psychiatric disease. Outcomes over six years were linked to the Australian and New Zealand Dialysis and Transplant Registry.

RESULTS

The median participant age was 71 years (range 60-87). Probable and confirmed sarcopenia was present in 55.9% and severe sarcopenia with reduced functional testing in 11.7%. Over 6 years, overall mortality was 50 of the 77 patients (65%), principally from cardiovascular events, dialysis withdrawal and infection. There were no significant survival differences between patients with no, probable, confirmed, or severe sarcopenia, or between tertiles of the nutritional assessment score. After adjustment for age, dialysis vintage, mean arterial pressure (MAP) and the total comorbidity score, no sarcopenia category predicted mortality. However, the total comorbidity score [Hazard Ratio (HR) 1.27, Confidence Intervals (CI) 1.02, 1.58, p = 0.03] and MAP (HR 0.96, CI 0.94, 0.99, P = < 0.01) predicted mortality.

CONCLUSION

Sarcopenia is highly prevalent in elderly haemodialysis patients but is not an independent predictor of mortality. Haemodialysis patients have multiple competing risks for mortality which, in this study, was predicted by a lower MAP and a higher total comorbidity score.

TRIAL REGISTRATION

Recruitment commenced December 2011. The study was registered 10.01.2012 with the Australian New Zealand Clinical Trials Registry (ACTRN12612000048886).

Comparison of bioelectrical impedance analysis-derived phase angle in individuals with different weight status

OBJECTIVE

Obesity is characterized not only by an increase of fat mass but also by alterations in skeletal muscle. Bioimpedance analysis (BIA)-derived phase angle (PhA) may provide specific information on the inherent characteristics of fat-free mass, and is widely used as an index of poor nutritional status. The aim of this study was to describe whether and to what extent PhA varies depending on age, sex, and body mass index (BMI) in individuals with different weight status.

METHODS

We selected 1877 participants for this retrospective study (two weight status groups): 983 individuals with obesity (age 40 ± 13.9 y; BMI 39.5 ± 7.2 kg/m²) and 894 controls (age 40 ± 13.3 y; BMI 24.6 ± 2.7 kg/m²). Anthropometry and PhA at 50 kHz for the whole body were performed in all participants.

RESULTS

PhA was greater in men than in women, although a decline of PhA was observed with age, which was linear in women and occurred in men after 40 y of age. On the other hand, no significant differences were observed with increasing BMI in either sex; lower values might be observed when BMI >50 kg/m².

CONCLUSIONS

A more detailed appraisal of BIA-derived PhA in obesity is reported in the present study, providing basic data that might be taken into consideration in prevention and clinical nutrition. Further studies are needed to explore differences of PhA in individuals with different weight status.

Relationship Between Regional Adiposity Distribution and Incident Heart Failure in General Populations without Cardiovascular Disease

BACKGROUND

Obesity is associated with a high risk of heart failure. However, the contribution of regional fat distribution evaluated using bioimpedance analysis toward heart failure risk in the general population without cardiovascular disease has rarely been studied.

METHODS

This study included 483,316 participants without heart failure and cardiovascular disease from the UK Biobank study. The regional fat mass was determined by bioimpedance analysis and calculated by dividing the square of height in meters (kg/m²). This study evaluated the association of regional fat mass (arm fat index [AFI], trunk fat index [TFI], and leg fat index [LFI]) with the risk of incident heart failure and whether regional fat mass adds a further prognostic value for heart failure besides body mass index (BMI) in a large prospective cohort study.

RESULTS

During the median 12.1 years, 3134 incident heart failure cases occurred. After adjustment for BMI and other confounding factors, each 1-standard deviation increase in LFI was associated with a 21% lower heart failure risk even after adjusting for BMI and other confounding factors (hazard ratio [HR] 0.79; 95% confidence interval [CI], 0.73-0.85). However, we did not observe heart failure-associated risks with AFI and TFI (HR 1.04; 95% CI, 0.99-1.09; HR 0.97, 95% CI, 0.91-1.04, respectively). Subgroup analysis demonstrated that the protective role of LFI was more prominent in the elderly and female participants (P < .01).

CONCLUSION

Regional fat measurement other than BMI can improve heart failure risk stratification; leg fat plays a protective role, yet arm and trunk fat do not, in the general population without cardiovascular disease.

The weight for length in late preterm infants assessed with bioelectrical impedance is positively associated with anthropometric variables

INTRODUCTION

The fat mass (FM) is greater in late preterm than full term infants at 1 month post birth, which may be an additional risk factor for metabolic syndrome in adulthood.

OBJETIVES

To evaluate body composition (BC) in late preterm infants using bioelectrical impedance analysis (BIA) to determine which anthropometric parameters are associated with BC. Our hypothesis was that weight-for-length is associated with the length-normalized fat mass index (FMI) at 1 year of life.

MATERIALS AND METHODS

We carried out a prospective cohort study in 2 groups: late preterm infants and full term infants. We obtained BC data by BIA. We calculated the fat mass (FM), FMI, fat-free mass (FFM) and length-normalized fat-free mass index (FFMI) at 1, 6 and 12 months of life. After, we assessed the association of the FMI with anthropometric parameters using multiple linear regression analysis.

RESULTS

The study included 97 late preterm and 47 full term infants, although at 12 months of life, the BC assessment was performed on 66 and 33 infants, respectively. Late preterm infants, compared to full term infants, had a higher FFM at 1 month (4013 vs 3524 g), a higher weight velocity at 6 months (5480 g versus 4604 g) and a lower FFM (7232 vs 7813 g) and FFMI (12.55 vs 13.26) at 12 months of life. The multivariate regression analysis showed that the weight-for-length z-core at 12 months was positively associated with the FMI at 12 months in all infants.

CONCLUSION

The weight-for-length z-score at 12 months is strongly associated with the FMI at 1 year of life. Further studies are needed to investigate whether an increment in this anthropometric parameter may modulate the risk of chronic diseases.

Association of phase angle with sarcopenia in chronic musculoskeletal pain patients: a retrospective study

BACKGROUND

In chronic musculoskeletal pain patients, detection of sarcopenia is of significant clinical interest. Phase angle, which can be measured through bioelectrical impedance analysis (BIA), can detect sarcopenia; however, the evidence in chronic musculoskeletal pain patients is limited. This study aimed to assess the relationship between phase angle and sarcopenia in patients with chronic musculoskeletal pain. Our hypothesis was that phase angle would be a useful indicator to identify sarcopenia in patients with chronic musculoskeletal pain.

METHODS

A total of 190 patients (51 men and 139 women) with chronic musculoskeletal pain were included in this retrospective cross-sectional study. Patient data of backgrounds, numeric rating scale score for pain, skeletal muscle index, and phase angle assessed using BIA were retrospectively reviewed. Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria 2019.

RESULTS

A total of 51 patients (26.7%), including 10 men (19.6%) and 41 women (29.5%), were diagnosed with sarcopenia. Phase angle, sarcopenia-related factors, age, and body mass index (BMI) differed significantly in patients with and without sarcopenia. On multiple logistic regression analysis, the prevalence of sarcopenia was significantly correlated with phase angle and BMI. The areas under the curve exhibited high accuracy in discriminating sarcopenia in men and moderate accuracy in both sexes and in women.

CONCLUSIONS

Phase angle may be a valid discriminator of sarcopenia in patients with chronic musculoskeletal pain.

Impact of a ketogenic diet intervention during radiotherapy on body composition: V. Final results of the KETOCOMP study for head and neck cancer patients

PURPOSE

Patients with head and neck cancer (HNC) are at risk of malnutrition, especially during radiochemotherapy. We aimed to study the impact of a ketogenic diet (KD) versus an unspecified standard diet (SD) on body composition and survival in HNC patients undergoing radio(chemo)therapy.

METHODS

As part of a controlled clinical trial, non-metastasized HNC patients were enrolled into either a KD (N = 11) or an SD (N = 21) group between May 2015 and May 2021. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Overall and progression-free survival was assessed during regular follow-up.

RESULTS

A total of 7 KD and 21 SD patients completed the study and were eligible for comparative analysis. Chemotherapy was significantly associated with declines in all body composition parameters, while the KD had opposing, yet nonsignificant effects. In patients receiving chemotherapy, average weekly reductions of body mass (BM) and skeletal muscle mass (SMM) were 0.9 kg and 0.31 kg in the KD group versus 1.2 kg and 0.57 kg in the SD group, respectively. Patients in the KD group receiving no chemotherapy achieved an average increase of 0.04 kg BM and 0.12 kg SMM per week. After a median follow-up of 42 months (range 6.7-78 months) there were no significant differences in progression-free or overall survival between the groups.

CONCLUSION

The KD may partially counteract the detrimental effects of radiochemotherapy on body composition in HNC patients. This should encourage further research into KDs in frail cancer patient populations and motivate their implementation as complementary therapy for selected patients.

Sarcopenia in idiopathic pulmonary fibrosis: a prospective study exploring prevalence, associated factors and diagnostic approach

Background

Sarcopenia gained importance in the evaluation of patients with chronic respiratory diseases, including idiopathic pulmonary fibrosis (IPF), since it may impact negatively on clinical outcomes.

Aim

Aim of this study is to evaluate the prevalence and factors associated with sarcopenia, defined according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) 2019 definition, and to evaluate the prevalence of the single criteria that define the EWGSOP2 definition (muscle strength, muscle quantity and physical performance), in a cohort of consecutive patients with IPF prospectively followed up in 9 hospitals in Northern Italy between December 2018 and May 2021.

Methods

Enrolled patients underwent an extensive pulmonary and nutritional assessment, including bioelectrical impedance analysis, dynamometry and 4-m gait speed test, both at IPF diagnosis and at 6-month follow-up.

Results

Out of the 83 patients (81% males, mean age 72.5 years) with IPF at disease diagnosis enrolled in the study, 19 (22.9%) showed sarcopenia, including 2 (2.4%) with severe sarcopenia, 5 (6.0%) with confirmed sarcopenia and 12 (14.5%) with probable sarcopenia. Sarcopenia was associated with a significantly higher severity of the disease and sedentary lifestyle, while no differences were observed in regards to body mass index, history of weight loss and comorbidities between patients with and without sarcopenia. Out of the 64 patients without sarcopenia at baseline, 16 cases showed alteration of muscle quantity and/or physical performance. In the 51 patients with complete data at 6-month follow-up, there were no cases of severe sarcopenia, 1 case (2.0%) showed confirmed sarcopenia, while the prevalence of probable sarcopenia was 19.6% (10 cases). No differences in regards to antifibrotic treatment received and onset of gastrointestinal side effects were observed between patients with and without sarcopenia at follow-up.

Conclusions

The prevalence of sarcopenia in patients with IPF both at diagnosis and at 6-month follow-up was low but not negligible and was associated with higher severity of the disease and sedentary lifestyle. In IPF patients, a comprehensive diagnostic work-up including all the criteria defining the EWGSOP2 definition might be more useful than a series testing for prompt recognition of nutritional and physical performance abnormalities.

A height-weight formula to measure body fat in childhood obesity

Background

The assessment of body composition is central in diagnosis and treatment of paediatric obesity, but a criterion method is not feasible in clinical practice. Even the use of bioelectrical impedance analysis (BIA) is limited in children. Body mass index (BMI) Z-score is frequently used as a proxy index of body composition, but it does not discriminate between fat mass and fat-free mass. We aimed to assess the extent to which fat mass and percentage of body fat estimated by a height-weight equation agreed with a BIA equation in youths with obesity from South Italy. Furthermore, we investigated the correlation between BMI Z-score and fat mass or percentage of body mass estimated by these two models.

Methods

One-hundred-seventy-four youths with obesity (52.3% males, mean age 10.8 ± 1.9) were enrolled in this cross-sectional study. Fat mass and percentage of body fat were calculated according to a height-weight based prediction model and to a BIA prediction model.

Results

According to Bland–Altman statistics, mean differences were relatively small for both fat mass (+ 0.65 kg) and percentage of body fat (+ 1.27%) with an overestimation at lower mean values; the majority of values fell within the limits of agreement. BMI Z-score was significantly associated with both fat mass and percentage of body fat, regardless of the method, but the strength of correlation was higher when the height-weight equation was considered (r = 0.82; p < 0.001).

Conclusions

This formula may serve as surrogate for body fat estimation when instrumental tools are not available. Dealing with changes of body fat instead of BMI Z-score may help children and parents to focus on diet for health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13052-022-01285-8.

Consistency of the estimated target weights and ECW/TBW using BIA after hemodialysis in patients between standing and lying-down positions

Background

As hemodialysis is administered with the patient lying down, the distribution of body fluid is stable in the lying position, which is why this position is recommended for bioimpedance analysis (BIA). Although the InBody S10 is widely used for hemodialysis patients in the lying position, clinicians must make the measurements in person. In contrast, patients can use the InBody 770 to obtain measurements by themselves in the standing position, which may be more convenient. Therefore, this study compared the measurements of hemodialysis patients’ estimated target weight and ECW/TBW obtained lying down using the S10 to those obtained in the standing position using the 770.

Methods

This study was conducted among maintenance hemodialysis patients at Chuncheon Sacred Heart Hospital in October 2020. Measurements from 56 patients before and after hemodialysis were obtained using the 2 machines. Each (S10 or 770) estimated target weight, both pre- and post-hemodialysis, was considered ideal when the ECW/TBW ratio was 0.380. R² was calculated and the Bland-Altman test was performed.

Results

The patients’ median age was 64 years old, and 51% were men. The actual ultrafiltration was 2 kg, and the mean TBW change measured using the InBody devices was 1.5 L (R² = 0.718) for the S10 and 1.7 L (R² = 0.616) for the 770. The estimated target weight at pre- and post-hemodialysis showed a remarkably high correlation with the patients’ actual pre- and post-hemodialysis weight (R² > 0.095). The correlation between these measurements (lying vs. standing) before and after hemodialysis was also very close (R² = 1.0000). In addition, ECW/TBW had a good correlation (R2 ≥ 0.970) The Bland-Altman test of dry weight and ECW/TBW yielded similar results.

Conclusions

This study showed that patients’ estimated target weights in the lying position using the InBody S10 device and in the standing position using the InBody 770 device were consistent in both pre- and post-hemodialysis states.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02737-3.

Comparison between two solute equations and bioimpedance for estimation of body fluid volumes

Background

The extracellular volume (ECV) and intracellular volume (ICV) estimated by bioimpedance analysis (BIA) deviates markedly from the textbook volumes of 20% and 40% of the body weight (BW). We estimated the transcellular exchange of water by calculating solute equilibriums after fluid challenges to examine whether the BIA or the textbook volumes are likely to be most correct.

Methods

Data was retrieved from 8 healthy male volunteers who received 25 mL/kg of Ringer’s solution or 3–5 mL/kg of hypertonic (7.5%) saline over 30 min after the ECV and ICV had been estimated by BIA. The exchange of water between the ECV and the ICV was calculated according to a sodium equation and an osmolality equation. Simulations were performed, where deviating body fluid volumes were applied.

Results

The mean ECV measured with BIA was 24.9% of BW (p < 0.05 versus the “textbook” volume). Mean ICV measured with BIA was 22.3% of BW (p < 0.05). The sodium and osmolality equations correlated closely with respect to the translocation of water across the cell membrane (r² = 0.86). By applying the “textbook” ECV, the sodium equation indicated that Ringer’s solution exchanged negligible amounts of water, while hypertonic saline withdrew 1.4 L from the ICV to the ECV. By contrast, applying the BIA-derived ECV to the sodium equation implied that 3 L of water would be translocated from the ECV to the ICV once hypertonic saline was administered.

Conclusion

The “textbook” ECV and ICV volumes but not the BIA-derived volumes were consistent with the fluid shifts obtained by two solute equations.

Role of the new bioimpedance monitoring device (Seca®) in assessing dry weight in hemodialysis patients

BACKGROUND

In recent years, bioimpedance analysis has come to be widely used in clinical practice for dialysis patients, but there is not sufficient consensus on its significance. We aimed to examine the merits of performing bioimpedance analysis in addition to conventional evaluation methods for dry weight such as measuring human atrial natriuretic peptide (hANP), blood pressure, and cardiothoracic ratio in patients on chronic hemodialysis.

METHODS

Body composition of 78 hemodialysis patients was performed by using a new and more accurate segmental multifrequency bioimpedance analysis device (Seca^® medical body composition analyzer 525, Seca GmbH & Co. KG, Hamburg, Germany). Laboratory data including hANP at post-dialysis and demographic profile were collected. Statistical analysis was performed with SPSS software.

RESULTS

Mean age of the patients was 66.9 ± 12.6 years and 80.8% were males. Mean value of hANP and the ratio of extracellular water to total body water (ECW/TBW) were 61.4 ± 36.4 pg/mL and 46.1 ± 3.9%, respectively. The calculated ECW/TBW cutoff point for hANP > 50 pg/mL was 45.0%, with sensitivity of 74.4% and specificity of 64.7%. Patients with an ECW/TBW of more than 45% and hANP value of > 50 pg/mL had a higher blood pressure and cardiothoracic ratio on chest X-ray examination.

CONCLUSIONS

Our results suggest that the ratio of extracellular water to total body water of more than 45% and hANP value of ≥ 50 pg/mL were overhydrated in chronic hemodialysis patients. Whether monitoring levels of these parameters has a role in the outcome including patients' survival and cardiovascular events requires further study.

Characteristics of malnutrition according to Global Leadership Initiative on Malnutrition criteria in non-surgical patients with irritable bowel disease

OBJECTIVE

Malnutrition is common in patients with inflammatory bowel disease (IBD). The Global Leadership Initiative on Malnutrition (GLIM) was proposed to assess the severity and characteristics of malnutrition. Thus, we aimed to use the latest consensus on the diagnosis of malnutrition, GLIM criteria, to evaluate malnutrition in patients with IBD.

METHODS

We performed a retrospective cohort study of 73 adult patients with IBD (48 with Crohn disease and 25 with ulcerative colitis). Demographic data, clinical characteristics, and nutrition status defined by Nutritional Risk Screening (NRS) 2002 and GLIM criteria were recorded at enrollment.

RESULTS

According to the GLIM criteria, 43 (58.90%) patients were identified with malnutrition, and the incidence of mild to moderate malnutrition and severe malnutrition was 28.77% (21 of 73 patients) and 30.14% (22 of 73 patients), respectively. The severity of malnutrition in patients with IBD increased with the cumulative number of phenotypic criteria they met (P < 0.01). The difference in the number of etiologic indicators was only identified between patients with severe malnutrition and those without malnutrition (P < 0.05). Patients with Crohns disease had a significantly higher rate of muscle mass loss than patients with ulcerative colitis (P = 0.038) but a lower incidence of reduced food intake or assimilation (P = 0.039).

CONCLUSION

The prevalence of malnutrition according to the GLIM criteria was high in non-surgical patients with IBD, and as the degree of malnutrition worsened, more phenotypes and etiologic types appeared. The phenotypic and etiologic characteristics of GLIM were different in patients with Crohn disease than in those with ulcerative colitis.

Bedside sonographic assessments for predicting predialysis fluid overload in children with end-stage kidney disease

Although the number of studies evaluating methods to predict fluid overload is increasing, the assessment of fluid status in children on dialysis is still fraught with inaccuracies. We aimed to evaluate the predictive capability of lung ultrasounds and the inferior vena cava collapsibility index (cIVC) in predialysis overhydration in children with end-stage kidney disease. Ten children with end-stage kidney disease who were on an intermittent hemodialysis program were included. The hydration status of the patients was clinically evaluated. Moreover, 30 predialysis and 30 postdialysis lung ultrasound, cIVC, and bioimpedance spectroscopy (BIS) measurements were performed. The median age of the participants was 14 (IQR, 13-15) years, and two (20%) were male. There was a strong positive correlation between the predialysis total number of B-lines and predialysis fluid overload (r=0.764, p<0.001). Additionally, there was a moderate negative correlation between predialysis cIVC and predialysis fluid overload (r=-0.599, p=0.002). Although the moderate correlation was determined between the postdialysis fluid overload and total number of B-lines, no correlation was determined using cIVC. Receiver operating characteristic curves demonstrated that the total number of B-lines and cIVC could successfully predict the predialysis fluid overload (relative hydration >7% derived from the BIS; AUROC 0.82 and 0.80, respectively). When both evaluations were combined, if either the total number of B-lines or the cIVC was outside the corresponding cutoff range (>10.5 and ≤23.5, respectively), it was detected in 16 out of 17 sessions (sensitivity 94%). If either one was outside the corresponding cutoff range (total number of B-lines >10.5 and cIVC ≤18.2), the severe predialysis fluid overload was predicted successfully in all eight (100%) sessions. Conclusion: Randomized controlled studies are needed to prove the reliability of the combined use of lung ultrasounds and cIVC in the assessment of predialysis fluid overload. What is Known: • The association of chronic fluid overload with increased morbidity and mortality raises the need for optimal determination of fluid overload in pediatric patients who are dialysis-dependent at a young age. • The linear correlation between the total number of B-lines on lung ultrasound images and fluid overload by weight has been shown. What is New: • This study evaluates the lung ultrasound and inferior vena cava collapsibility index combined in predicting fluid overload in dialytic children. • If either the total number of B-lines or the cIVC was outside the corresponding cutoff range (>10.5 and cIVC ≤18.2, respectively), the severe predialysis fluid overload was predicted successfully in all eight (100%) sessions.

Bioelectrical impedance (BIA)-derived phase angle in adults with obesity: A systematic review

BACKGROUND & AIMS

Bioimpedance analysis-derived phase angle (PhA), as marker of body cell mass and cell integrity, might be altered in obesity, a condition which is characterized by alterations in muscle structure and function. The aim of this systematic review was to evaluate whether and to which extent PhA varies in individuals/patients with excess body weight focusing on: a) changes in PhA due to obesity; b) changes in PhA after bariatric interventions or training programs.

METHODS

According to PRISMA criteria, a systematic literature search until February 2021 using PubMed, Embase, Scopus, and Web of Science was performed. Selection criteria included studies on patients with obesity without comorbidities other than metabolic diseases.

RESULTS

A total of 278 articles were first identified. After removing duplicates and excluding studies that did not fulfil the inclusion criteria, the full text of the remaining 80 potentially relevant studies was examined to finally retrieve 11 cross-sectional and 10 longitudinal studies. Few studies have shown that PhA is lower in individuals/patients with obesity than in controls. The only study on the matter showed a decrease with age after the fourth decade of life. Four out of five studies reported consistently greater mean values in men than in women. In two studies PhA was lower in patients with severe obesity; in addition, Patients with low PhA had higher BMI and PhA was inversely correlated with fat mass. Longitudinal studies showed that PhA markedly decreased after bariatric surgery and slightly increased after training programs.

CONCLUSIONS

Thus, a relatively low number of studies have evaluated PhA in individuals/patients with obesity with sometimes contradictory and preliminary results. PhA might be useful to evaluate muscle quality in individuals/patients with obesity but further studies are needed to more accurately associate this variable with changes in muscle structure and strength, as well as in metabolic functions.

Impact of a ketogenic diet intervention during radiotherapy on body composition: IV. Final results of the KETOCOMP study for rectal cancer patients

BACKGROUND & AIMS

Obesity and low muscle mass are associated with worse outcomes of colorectal cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in rectal cancer patients undergoing radiotherapy.

METHODS

Patients with non-metastasized rectal cancer were allocated to either the KD (N = 24) or the SD (N = 25) group during radiotherapy. Body composition was measured weekly by bioimpedance analysis and analyzed using linear mixed effects models. Pathologic response in patients undergoing neoadjuvant treatment was evaluated at the time of surgery.

RESULTS

A total of 18 KD and 23 SD patients completed the study and were eligible for analysis. The SD group experienced no noteworthy changes in any body composition parameter. In contrast, patients in the KD group lost significant amounts of body weight and fat mass, averaging 0.5 and 0.65 kg/week (p < 0.0001). There was a rapid loss of intracellular water consistent with initial intramuscular glycogen and water depletion, but skeletal muscle tissue was conserved. Pathological tumor responses were somewhat greater in the KD group, with a larger mean Dworak regression grade (p = 0.072) and larger percentage of near-complete (yT0N0 or yT1N1) responses (43 versus 15%, p = 0.116) that almost reached statistical significance in intention-to-treat analysis (50% versus 14%, p = 0.018).

CONCLUSIONS

In rectal cancer patients undergoing curative radiotherapy, a KD significantly reduced body weight and fat mass while preserving skeletal muscle mass. We could demonstrate a trend for KDs contributing synergistically to pathological tumor response, a finding in line with preclinical data that warrants future confirmation in larger studies.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.

Protein-enriched diet improved muscle endurance and marginally reduced intramuscular adiposity: Results from a randomized controlled trial among middle-aged and older adults

BACKGROUND

Maintaining sufficient dietary protein intake is important for nutritional status, muscle mass, and healthy aging, but the clinical effects of high protein diet remained controversial..

METHODS

This 12-week randomized controlled trial enrolled community-dwelling middle-aged and older adults to evaluate clinical effects of daily diet with different protein density.. All participants received 10 frozen meals per week for 12 weeks containing either 15% daily calorie of protein (regular-protein group, RPG), or 25% daily calorie of protein (high-protein group, HPG). Bioimpedance analysis was used to assess body composition, and the magnetic resonance imaging on both mid-thighs was performed to measure muscle mass and the intramuscular adiposity.

RESULTS

This trial enrolled 70 participants, and data of 52 participants (mean age: 53.7 ± 8.3 years, 53.8% male; 25 in RPG and 27 in HPG) were available for analysis. Baseline demographic characteristics, functional assessment, body composition and muscle parameters, and laboratory data were similar between groups. During the study period, participants of both groups significantly reduced body weight, body mass index, total body fat percentage, and handgrip strength, but not in the relative appendicular muscle mass). Compared to participants of RPG, HPG participants showed significant improvement in 6-minute walking distance, increased high-sensitivity C-reactive protein and marginal reduction in intramuscular adiposity than RPG participants.

CONCLUSIONS

Higher dietary protein intake significantly improved physical endurance and marginally reduced intramuscular adiposity, but increased the inflammatory biomarker among middle-aged and older adults. Further study is needed to explore long-term effects of high-protein diet among middle-aged and older adults..

A proposal for reference values of hand grip strength in women with different body mass indexes

OBJECTIVE

Hand grip strength (HGS) is frequently used in clinical practice, resulting in a potential marker of nutritional status. This study aimed to develop reference values of HGS in Italian women with different categories of body mass index (BMI). Additionally, the main predictors of HGS were identified.

METHODS

A cross-sectional study was conducted in Italian women between ages 16 and 55 y with different categories of BMI at the Department of Clinical Medicine and Surgery, Federico II University Hospital, Naples Italy. The whole sample was divided into tertiles according to BMI: 15 to 17.29 kg/m² (T1), 17.3 to 19.9 kg/m² (T2), and 20 to 25 kg/m² (T3). Anthropometry, bioimpedance analysis, and muscle strength by an HGS test were evaluated. The cut-off values for HGS were developed for all participants and stratified by age group. Finally, a multivariate linear regression analysis was performed to assess the main predictors of HGS.

RESULTS

A total of 529 women with a mean age of 23.2 ± 7.0 y and an average BMI of 18.9 ± 2.5 kg/m² were analyzed. HGS was higher for the dominant hand than for the non-dominant hand in all BMI tertiles. On both sides, according to age groups, HGS increased with increasing age in T1 and T3, whereas it increased in the women between ages 20 and 30 y in T2 only. Multivariate linear regression analysis showed that predictors of HGS varied according to tertiles. Specifically, we found that body weight (R² = 0.252) was the main predictor in T1, whereas phase angle (PhA) was the main determinant in both T2 (R² = 0.240) and T3 (R² = 0.216).

CONCLUSION

This study defined the normal reference values of HGS in Italian women with different BMI ranges, stratifying the sample group by age. Additionally, the main predictors of HGS were assessed for each BMI tertile. In primary malnutrition (T1), the main predictor of HGS was body weight, whereas in the other two tertiles (T2, T3), the PhA was the main predictor of HGS.

Association of an Overhydrated State With the Liver Fibrosis and Prognosis of Cirrhotic Patients

BACKGROUND/AIM

A bioimpedance analysis (BIA) can indicate an overhydrated state as the extracellular water/total body water (ECW/TBW) value. This study aimed to assess the clinical significance of this value in patients with chronic liver diseases (CLDs).

PATIENTS AND METHODS

A total of 552 CLD patients who received a liver biopsy and underwent anthropometric assessment and BIA-based body composition analysis were enrolled. The association of the ECW/TBW value with the liver fibrosis and nutritional status was assessed. The relationship between the ECW/TBW value and the prognosis of cirrhotic patients (N=209) was also evaluated.

RESULTS

The ECW/TBW value increased as liver fibrosis progressed and was also related to decreased muscle mass/sarcopenia. The presence of overhydration was associated with a poor prognosis of cirrhotic patients.

CONCLUSION

An increased ECW/TBW value was associated with progressive liver fibrosis and malnutrition and related to the prognosis of cirrhotic patients.

Arm Skeletal Muscle Mass Is Associated With the Prognosis of Patients With Cirrhosis

BACKGROUND/AIM

This study aimed to assess the clinical significance of measuring the arm skeletal muscle mass in patients with cirrhosis.

PATIENTS AND METHODS

Using body composition data measured with the bioimpedance analysis (BIA) method, the skeletal muscle mass index (SMI) values of the arm (arm skeletal muscle mass/height²) and leg (leg skeletal mass muscle/height²) were calculated for 353 patients with cirrhosis, and the relationships of these indices to their prognosis were assessed. In addition, overhydration of the upper and lower limbs was compared.

RESULTS

Arm SMI was significantly positively associated with the prognosis of patients with cirrhosis (p=0.0002) but leg SMI was not (p=0.0829). The rate of overhydration in the lower limbs was significantly higher than that in the upper limbs (p<0.0001).

CONCLUSION

Arm SMI measured with the BIA method was suggested to be minimally affected by water retention, and might be clinically useful for patients with cirrhosis.

New predictive equations for estimating resting energy expenditure in subjects with normal weight and overweight

OBJECTIVE

The aim of this study was to develop and validate new predictive equations for estimating resting energy expenditure (REE) in subjects with normal weight and overweight, considering anthropometric parameters as well as raw variables from bioimpedance analysis (BIA).

METHODS

Adult participants with normal weight and overweight were recruited and randomly split into calibration and validation groups. Indirect calorimetry (IC) and BIA were performed in all subjects. New predictive equations were developed using the following models: model 1 with age, weight, stature, and body mass index (BMI) as predictors; and model 2: model 1 + raw BIA variables (bioimpedance index and phase angle). The accuracy of the new equations at both the group (bias) and individual (within ±10%) levels was tested in the validation group. Three published predictive equations were also compared, with the REE values measured by IC.

RESULTS

A total of 2483 adults were included for developing and validating the new equations. All selected formulas, including the new ones, showed a bias of <5% in estimating REE at the group level. Accuracy at the individual level was slightly higher for the new equations, especially for the equation based on raw BIA variables (men = 70.3%; women = 72.3%).

CONCLUSIONS

Compared to the equations in the literature, the new equations showed good accuracy at both the group and individual levels, with a slight improvement in individual accuracy for the formula including raw BIA variables. However, future research is required to verify the role of the raw BIA variables in predicting REE in subjects with normal weight and overweight.

Short-term effects of a Paleolithic lifestyle intervention in breast cancer patients undergoing radiotherapy: a pilot and feasibility study

Evolutionary principles are rarely considered in clinical oncology. We here aimed to test the feasibility and effects of a dietary and physical activity intervention based on evolutionary considerations in an oncological setting. A total of 13 breast cancer patients referred to our clinic for curative radiotherapy were recruited for this pilot study. The women were supposed to undertake a "Paleolithic lifestyle" (PL) intervention consisting of a Paleolithic diet and daily outdoor activity of at least 30 min duration while undergoing radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters were assessed before, during, and at the end of radiotherapy. A control group on an unspecified standard diet (SD) was assigned by propensity score matching. A total of eleven patients completed the study. The majority of patients (64%) reported feeling good or very good during the intervention. The intervention group experienced an average decrease of 0.4 kg body weight (p < 0.001) and 0.34 kg (p < 0.001) fat mass per week, but fat-free and skeletal muscle mass were not significantly affected. Vitamin D levels increased slightly from 23.8 (11-37.3) ng/ml to 25.1 (22.6-41.6) ng/ml (p = 0.053). β-hydroxybutyrate levels were significantly increased and triglycerides and free T3 hormone levels significantly reduced by the PL intervention. This pilot study shows that adoption of a PL intervention during curative radiotherapy of breast cancer patients is feasible and able to reduce fat mass. Daily outdoor activity could eliminate vitamin D deficiency (vitamin D < 20 ng/ml). Future studies are needed to confirm these findings.

The Anthropometric Assessment With the Bioimpedance Method Is Associated With the Prognosis of Cirrhotic Patients

BACKGROUND/AIM

The bioimpedance analysis (BIA) can provide anthropometric data on patients. The aim of the study is to evaluate the clinical relevance of these automatically obtained values.

PATIENTS AND METHODS

We studied the arm circumference (AC) and arm muscle circumference (AMC) of 197 histologically proven cirrhotic patients. The BIA-based anthropometric data were compared to the manually measured data. In addition, we evaluated whether or not the BIA-based anthropometric data were associated with the prognosis of the patients.

RESULTS

The data of %AC and %AMC obtained using the two methods were well correlated (p<0.001) with relatively inconspicuous differences (approximately 6.0% for %AC and 16.0% for %AMC). The data of %AC and %AMC obtained from the BIA method were significantly associated with the prognosis of the patients.

CONCLUSION

The BIA-based anthropometric data were associated with the direct measurement data and related to the prognosis of cirrhotic patients.

Bioelectrical impedance analysis (BIA) -derived phase angle in sarcopenia: A systematic review

BACKGROUND & AIMS

Bioelectrical impedance analysis-derived phase angle (PhA) has been gaining attention in the clinical evaluation of nutritional status because it is thought to be a proxy of water distribution and body cell mass; it is also associated to muscle strength and is an effective predictor of different clinical outcomes. Since an association may be expected between PhA and sarcopenia (defined by low skeletal muscle mass and impaired muscle function), the aim of this systematic review was to evaluate: a) changes in PhA due to sarcopenia; b) prevalence of sarcopenia according to PhA values; c) derivation of phase angle cut-offs for detecting sarcopenia; d) sarcopenia and PhA as predictors of clinical outcomes.

METHODS

A systematic research on electronic databases (PubMed, Embase, Scopus and Web of Science) from inception to January 31st, 2020 was performed according to PRISMA checklist. Using PICOS strategy, "P" corresponded to participants of any age, gender or ethnicity, "I" designated diagnosis of sarcopenia, "C" indicated subjects without sarcopenia, "O" corresponded to PhA, and "S" selected all study types. Methodological quality was assessed using the National Institute of Health (NIH) quality assessment tool.

RESULTS

Through the initial literature search and after removing duplicates and excluding papers by screening titles and abstracts, 79 potentially relevant studies were examined. Thirteen studies (7668 subjects) met the inclusion criteria. The overall risk of bias was low. Sarcopenia was associated with a significant lower PhA in seven studies out of eight, while five studies out of six reported a high prevalence of sarcopenia was in patients with low PhA. Different cut-off point values from 4.05 to 5.05° have been derived for the identification of sarcopenia. PhA and sarcopenia were independent predictors of survival in cancer patients and geriatric hospitalized patients.

CONCLUSIONS

Data from the selected papers demonstrate that PhA is decreased in sarcopenic subjects and the prevalence of sarcopenia is higher in subjects with low PhA. Further studies are needed to determine to what extent PhA may be valuable in detecting low muscle quality and/or identifying sarcopenia.

Estimation of skeletal muscle mass by bioimpedance and differences among skeletal muscle mass indices for assessing sarcopenia

BACKGROUND

It is crucial to assess age-related muscle mass changes and derived indices differences in geriatric medicine. We aimed to develop and validate four bioimpedance analysis (BIA) prediction equations against dual-energy X-ray absorptiometry (DEXA) and magnetic resonance image (MRI) in estimating skeletal muscle mass and to compare the differences among skeletal muscle mass indices, cutoff values, and corresponding prevalence rates of low muscle mass for assessing sarcopenia in Chinese adults.

METHODS

We measured the height (Ht), weight (Wt), appendicular lean mass (ALM) or skeletal muscle mass (ASM), total lean body mass (LBM) or skeletal muscle mass (TSM) obtained using DEXA or MRI, and a multi-frequency BIA (BCA _II;50, 250 kHz), in 371 adults aged 18.0-87.0 years. We also collected gender, age, Ht, Wt, and impedance indexes (Ht²/R₅₀, Ht²/R₂₅₀, R₅₀/Ht², R₂₅₀/Ht²) from 30,500 adults aged 18-96 years living in China. Multiple regression analyses were used to derive four prediction equations by BIA, and double cross-validation techniques and Bland-Altman analyses were used to test agreement. Various muscle mass indices and prevalence rates were depicted by line plots in regard to age trends.

RESULTS

Satisfactory results were found in the four prediction models as they had the larger R² (0.833-0.930) values and low SEE (1.409-2.335 kg) values. The predictive variables included impedance indexes (Ht²/R₅₀, R₅₀/Ht², R₂₅₀/Ht²), gender, age, Wt, and Ht. The corresponding prevalence rates of low muscle mass exhibited significant differences according to the various muscle mass indices adjusted for Ht, Wt, or body mass index (BMI), in addition to the cutoff values based on two standard deviations (2SD) of young people or the lower 20% of the study group.

CONCLUSIONS

The BIA equations have the potential to be applied as a practical method of quantifying skeletal muscle mass in Chinese adults. However, the operational methods that are most appropriate for determining the degree of low muscle mass that actually contributes to sarcopenia remains inconclusive.

Feasibility of computed tomography-based assessment of skeletal muscle mass in hemodialysis patients

BACKGROUND

Sarcopenia is a major health issue especially in patients on maintenance hemodialysis. Low skeletal muscle mass is included in the diagnostic criteria for sarcopenia. The skeletal muscle mass is usually evaluated by modalities such as bioimpedance analysis (BIA) or dual-energy X-ray absorptiometry, however the assessment of skeletal muscle mass using computed tomography (CT) images has not been established. The purpose of the study was to investigate the feasibility of the assessment of skeletal muscle mass using CT images in hemodialysis patients.

METHODS

Skeletal muscle mass index (SMI) was measured by BIA and psoas muscle index (PMI) was measured by cross-sectional CT images in 131 patients. The relationship between SMI and PMI and the diagnostic ability of PMI for low muscle mass were evaluated. Furthermore, the patients were followed up and long-term survival in patients with low and high PMI were compared.

RESULTS

PMI measured at the L3 vertebral level was strongly correlated with SMI (r = 0.597, p < 0.001). Age, sex, and SMI were the influencing factors for PMI. Patients with low PMI showed higher incidence rates of mortality during the follow up.

CONCLUSIONS

PMI assessed by CT image can be an alternative to BIA in patients on hemodialysis.

Validation of population-based cutoffs for low muscle mass and strength in a population of Turkish elderly adults

BACKGROUND

Despite differences between the studies regarding methods for estimating low muscle mass, the European Working Group on Sarcopenia in Older People (EWGSOP) recommends use of two standard deviations (SDs) below the reference sex-specific means of healthy young adults.

AIMS

The aim of this study was to determine the cutoff points of skeletal muscle mass index (SMI) and handgrip strength (HS) in Turkish population and to compare the power of different cutoff points to predict comprehensive geriatric assessment (CGA) parameters.

METHODS

Two hundred and eight young healthy volunteers (104 women, 104 men) were included in the study to define SMI, HS cutoff values. 1150 older adults (784 women, 366 men) underwent CGA, including physical performance, activities of daily living (ADL), HS and frailty. Body composition was obtained from every participant by bioimpedance analysis (BIA). CGA parameters of sarcopenic patients according to EWGSOP and new Turkish cutoff points were compared.

RESULTS

SMI cutoff points were defined 5.70 kg/m² for women, 8.33 kg/m² for men. HS thresholds were calculated as 14 kg for women, 28 kg for men using measurements of healthy young adult reference. Considering the new threshold values, the prevalence of sarcopenia was 10% (7% women, 17% men). When new sarcopenia criteria were applied and covariates were adjusted, sarcopenia was found to be more closely related to ADL impairment, balance, frailty in men, and balance, slow walking speed, ADL impairment, frailty in women (p < 0.05).

DISCUSSION

Muscle mass and strength may vary between populations because of ethnicity and other related discrepancies. The evaluation of sarcopenia according to the present guidelines may cause overdiagnosis in some populations.

CONCLUSION

Cutoff points specific to populations should be determined.

Impact of a ketogenic diet intervention during radiotherapy on body composition: III-final results of the KETOCOMP study for breast cancer patients

Background

Obesity and low muscle mass are associated with worse outcomes of breast cancer patients. We conducted a controlled trial to study the impact of a ketogenic diet (KD) based on natural foods versus an unspecified standard diet (SD) on body composition in breast cancer patients undergoing radiotherapy.

Methods

Patients with non-metastasized breast cancer were allocated to either the KD (N = 32) or the SD (N = 31) during radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters and quality of life were assessed before, during, and at the end of radiotherapy.

Results

A total of 29 KD and 30 SD patients completed the study. During radiotherapy, mean and median fasting BHB concentrations in the KD group were 0.72 and 0.49 mmol/l (range 0.06–4.9) which was significantly higher than those in the SD group (p < 2.2 × 10⁻¹⁶). There was a very small and insignificant increase in body weight and fat mass in the SD group, as well as a decrease of fat free mass. In contrast, patients in the KD group lost body weight and fat free and skeletal muscle mass quickly after diet onset, which for the most part was related to water losses. The KD did not cause further substantial changes in fat free or skeletal muscle mass, but was associated with a gradual decrease of 0.4 kg body weight and fat mass per week (p < 0.0001). The KD significantly decreased free T3 levels by 0.06 pg/ml/week (p = 6.3 × 10⁻⁵). Global quality of life remained stable in the SD group but increased in the KD group from a score of 66.7 to 75.0 (p = 0.20).

Conclusions

In breast cancer patients undergoing curative radiotherapy, a KD based on natural foods is feasible. After initial water losses, the KD tends to reduce body weight and fat mass while preserving fat free and skeletal muscle mass.

Trial registration

ClinicalTrials.gov identifier: NCT02516501, registered on August 06, 2015.

Assessment of Hydration Status in Peritoneal Dialysis Patients: Validity, Prognostic Value, Strengths, and Limitations of Available Techniques

BACKGROUND

The majority of patients undergoing peritoneal dialysis (PD) suffer from volume overload and this overhydration is associated with increased mortality. Thus, optimal assessment of volume status in PD is an issue of paramount importance. Patient symptoms and physical signs are often unreliable indexes of true hydration status.

SUMMARY

Over the past decades, a quest for a valid, reproducible, and easily applicable technique to assess hydration status is taking place. Among existing techniques, inferior vena cava diameter measurements with echocardiography and natriuretic peptides such as brain natriuretic peptide and N-terminal pro-B-type natriuretic peptide were not extensively examined in PD populations; while having certain advantages, their interpretation are complicated by the underlying cardiac status and are not widely available. Bioelectrical impedance analysis (BIA) techniques are the most studied tool assessing volume overload in PD. Volume overload assessed with BIA has been associated with technique failure and increased mortality in observational studies, but the results of randomized trials on the value of BIA-based strategies to improve volume-related outcomes are contradictory. Lung ultrasound (US) is a recent technique with the ability to identify volume excess in the critical lung area. Preliminary evidence in PD showed that B-lines from lung US correlate with echocardiographic parameters but not with BIA measurements. This review presents the methods currently used to assess fluid status in PD patients and discusses existing data on their validity, applicability, limitations, and associations with intermediate and hard outcomes in this population. Key Message: No method has proved its value as an intervening tool affecting cardiovascular events, technique, and overall survival in PD patients. As BIA and lung US estimate fluid overload in different compartments of the body, they can be complementary tools for volume status assessment.

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.

Utility of published skinfold thickness equations for prediction of body composition in very young New Zealand children

Measurement of body composition is increasingly important in research and clinical settings but is difficult in very young children. Bioelectrical impedance analysis (BIA) and air displacement plethysmography (ADP) are well-established but require specialist equipment so are not always feasible. Our aim was to determine if anthropometry and skinfold thickness measurements can be used as a substitute for BIA or ADP for assessing body composition in very young New Zealand children. We used three multi-ethnic cohorts: 217 children at a mean age of 24·2 months with skinfold and BIA measurements; seventy-nine infants at a mean age of 20·9 weeks and seventy-three infants at a mean age of 16·2 weeks, both with skinfold and ADP measurements. We used Bland-Altman plots to compare fat and fat-free mass calculated using all potentially relevant equations with measurements using BIA or ADP. We also calculated the proportion of children in the same tertile for measured fat or fat-free mass and tertiles (i) calculated using each equation, (ii) each absolute skinfold, and (iii) sum of skinfold thicknesses. We found that even for the best equation for each cohort, the 95 % limits of agreement with standard measures were wide (25-200 % of the mean) and the proportion of children whose standard measures fell in the same tertile as the skinfold estimates was ≤69 %. We conclude that none of the available published skinfold thickness equations provides good prediction of body composition in multi-ethnic cohorts of very young New Zealand children with different birth history and growth patterns.

Extraction of bioimpedance phase information from its magnitude using a non-uniform Kramers-Kronig transform

A novel non-uniform Kramers-Kronig Transform algorithm for bioimpedance phase extraction is proposed and tested in this work. The algorithm error is studied and compared with a previously proposed phase extraction technique, also based on the Kramers-Kronig transform. Results using simulated datasets and experimental datasets confirm the excellent performance of the algorithm.

Supine equilibration of extracellular fluid in peritoneal dialysis varies with intra-abdominal pressure

BACKGROUND

Increased intra-abdominal pressure (PIA) leads to venous congestion in splanchnic and adjoining circulations. The aim is to examine whether PIA in peritoneal dialysis (PD) affects the mobilization of extracellular fluid from the lower body in supine body position.

METHODS

Patients were studied during a regular peritoneal equilibration test (PET) in supine body position using multifrequency bioimpedance analysis to determine extracellular resistance and absolute volume overload (AVO) in wrist-to-ankle (W2A) as well as in ankle-to-ankle (A2A) configurations. Measurements were taken at baseline (T0) after draining the peritoneal cavity, at T1 shortly after filling with 2 L of standard dialysate, and at T2 before taking the 2 h PET samples. PIA was measured from the column height in the PD catheter. Extracellular resistance in the lower extremities (RL) was taken as half of the A2A resistance.

RESULTS

Eighteen patients (56 ± 15 years, 76 ± 21 kg, body mass index (BMI) 26.4 ± 7 kg/m², 13 men) were studied. After having assumed a supine body position for the duration of 17, 77, and 155 min, AVO continuously decreased from 1.6 ± 1.3 (T0) to 1.2 ± 1.5 (T1) and 1.0 ± 1.4 L (T2). RL significantly increased from 238 ± 57 (T0) to 254 ± 62 (T1) and 264 ± 67 Ohm (T2). This increase was negatively correlated to BMI and PIA measured at any time point, but not to net ultrafiltration volume.

CONCLUSIONS

Orthostatic fluid shifts from the lower limbs may take up to 2 h in supine PD patients, especially with high BMI and PIA because of venous congestion in splanchnic and adjoining circulations.

Real-time and noninvasive detection of UV-Induced deep tissue damage using electrical tattoos

Understanding longterm deep tissue damage caused by UV radiation is imperative for ensuring the health and safety of living organisms that are regularly exposed to radiation sources. While existing UV dosimeters can quantify the cumulative amount of radiation to which an organism is exposed, these sensors cannot reveal the presence and extent of internal tissue damage caused by such exposure. Here we describe a method that uses conducting polymer tattoos to detect UV radiation-induced deep tissue damage in living organisms using bioimpedance analysis (BIA), which allows for noninvasive, real-time measurements of body composition and point-of-care assessment of clinical condition. To establish a performance baseline for this method, we quantify the effects of UVA radiation on live plant leaves. Low-energy UVA waves penetrate further into biological tissue, as compared to UVB, UVC and ionizing radiation, and cause longlasting deep tissue damage that cannot be immediately and readily detected using surface-sensitive techniques, such as photogrammetry and epidermal sensors. We show that single-frequency bioimpedance analysis allows for sensitive, real-time monitoring of UVA damage: as UVA dose increases, the bioimpedance of a plant leaf measured at a frequency of 1 kHz linearly decreases until the extent of radiation damage saturates and the specimen is effectively necrotized. We establish a strong correlation between radiation fluence, internal biological damage and the bioimpedance signal measured using our conducting polymer tattoos, which supports the efficacy of our method as a new type of internal biodosimetry.

The extracellular volume status predicts body fluid response to SGLT2 inhibitor dapagliflozin in diabetic kidney disease

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an antihyperglycemic drug with diuretic action. We recently reported that the SGLT2 inhibitor dapagliflozin ameliorates extracellular volume expansion with a mild increase in urine volume. However, the impact of the pretreatment extracellular volume status on the body fluid response to SGLT2 inhibitors remains unclear.

METHODS

Thirty-six diabetic kidney disease (DKD) patients were treated with dapagliflozin. The body fluid volume, including intracellular water (ICW), extracellular water (ECW) and total body water (TBW), were measured on baseline and day 7 using a bioimpedance analysis (BIA) device. The ECW/TBW and ECW were used as markers of the extracellular volume status. For a comparison, the extracellular volume status responses to loop diuretic furosemide (n = 16) and vasopressin V2 receptor antagonist tolvaptan (n = 13) were analyzed.

RESULTS

The body weight, brain natriuretic peptide and body fluid parameters measured by a BIA (ICW, ECW, TBW, and ECW/TBW) were significantly decreased for 1 week after dapagliflozin administration. The change in the ECW/TBW in the high-ECW/TBW group (over the median value of 0.413) was significantly higher than in the low-ECW/TBW group (- 2.1 ± 0.4 vs. - 0.5 ± 0.4%, p = 0.006). Only with dapagliflozin treatment (not furosemide or tolvaptan treatment) was the baseline ECW/TBW significantly correlated with the changes in the ECW/TBW (r = - 0.590, p < 0.001) and ECW (r = - 0.374, p = 0.025).

CONCLUSIONS

The pretreatment extracellular volume status predicts the body fluid response to the SGLT2 inhibitor dapagliflozin in DKD patients. The diminished extracellular fluid reduction effect of dapagliflozin in patients without severe extracellular fluid retention may contribute to maintaining a suitable body fluid status.

Agreement Between Body Composition Assessed by Bioelectrical Impedance Analysis and Doubly Labeled Water in Obese Women Submitted to Bariatric Surgery : Body Composition, BIA, and DLW

INTRODUCTION

Bariatric surgery has a significant influence on body composition (BC), which should be monitored. However, there is a need to recommend low-cost practical methods, with good estimation of BC for class III obese and/or bariatric patients.

OBJECTIVE

The aim of this study was to determine accuracy and agreement between BC assessed by direct segmental multifrequency bioelectrical impedance analysis (DSM-BIA) and doubly labeled water (DLW) as reference method.

MATERIAL AND METHODS

Twenty class III obese women (age 29.3 ± 5.1 years; body mass index 44.8 ± 2.4 kg/m²) underwent Roux-en-Y gastric bypass surgery. BC (fat mass [FM], fat-free mass [FFM], and total body water [TBW]) was assessed by InBody 230 and DLW in the following periods: before and 6 and 12 months after surgery. Accuracy between the methods was evaluated by the bias and root mean square error. Pearson's correlation, concordance correlation coefficient (CCC), and Bland-Altman method were used to evaluate agreement between the methods.

RESULTS

Correlations were significant (p < 0.001) and CCC was good/excellent between both methods for the evaluation of FM (r = 0.84-0.92, CCC = 0.84-0.95), FFM (r = 0.73-0.90, CCC = 0.68-0.80), and TBW (r = 0.76-0.91, CCC = 0.72-0.81) before and after bariatric surgery. In addition, no significant bias was observed between DSM-BIA and DLW for FM (mean error [ME] = - 1.40 to 0.06 kg), FFM (ME = 0.91-1.86 kg), and TBW (ME = 0.71-1.24 kg) measurements.

CONCLUSION

The DSM-BIA was able to estimate the BC of class III obese women submitted to bariatric surgery with values consistent with those of the DLW method.

Significance of serum Myostatin in hemodialysis patients

BACKGROUND

Malnutrition and muscle wasting are common in haemodialysis (HD) patients. Their pathogenesis is complex and involves many molecules including Myostatin (Mstn), which acts as a negative regulator of skeletal muscle. The characterisation of Mstn as a biomarker of malnutrition could be useful in the prevention and management of this condition. Previous studies have reported no conclusive results on the actual relationship between serum Mstn and wasting and malnutrition. So, in this study, we evaluated Mstn profile in a cohort of regular HD patients.

METHODS

We performed a cross-sectional study, enrolling 37 patients undergoing bicarbonate-HD (BHD) or haemodiafiltration (HDF) at least for six months. 20 sex-matched healthy subjects comprised the control group. Mstn serum levels were evaluated by ELISA before and after HD. We collected clinical and biochemical data, evaluated insulin resistance, body composition, malnutrition [by Malnutrition Inflammation Score (MIS)] and tested muscle function (by hand-grip strength, six-minute walking test and a questionnaire on fatigue).

RESULTS

Mstn levels were not significantly different between HD patients and controls (4.7 ± 2.8 vs 4.5 ± 1.3 ng/ml). In addition, while a decrease in Mstn was observed after HD treatment, there were no differences between BHD and HDF. In whole group of HD patients Mstn was positively correlated with muscle mass (r = 0.82, p < 0.001) and inversely correlated with age (r = - 0.63, p < 0.01) and MIS (r = - 0.39, p = 0.01). No correlations were found between Mstn and insulin resistance, such as between Mstn levels and parameters of muscle strength and fatigue. In multivariate analysis, Mstn resulted inversely correlated with fat body content (β = - 1.055, p = 0.002).

CONCLUSIONS

Circulating Mstn is related to muscle mass and nutritional status in HD patients, suggesting that it may have a role in the regulation of skeletal muscle and metabolic processes. However, also considering the lack of difference of serum Mstn between healthy controls and HD patients and the absence of correlations with muscle function tests, our findings do not support the use of circulating Mstn as a biomarker of muscle wasting and malnutrition in HD.

Perioperative fluid dynamics evaluated by bioelectrical impedance analysis predict infectious surgical complications after esophagectomy

BACKGROUND

Transthoracic esophagectomy, among the most invasive surgeries, is highly associated with postoperative infectious complications which adversely affect postoperative management including fluid dynamics. The aim of the study is to evaluate the utility of perioperative bioelectrical impedance analysis (BIA) measurements for the patients after transthoracic esophagectomy.

METHOD

Multi-frequency BIA measurements were conducted in 24 patients undergoing transthoracic esophagectomy preoperatively, at 1 h after surgery, and twice daily for the following 7 days. The amounts of extracellular water (ECW), internal cellular water (ICW), total body water (TBW), and fat-free mass (FFM) were calculated. Changing trends in variables were analyzed, and the patients were subdivided according to the presence of infectious surgical adverse events to identify differences in fluid dynamics.

RESULTS

ECW was the major body fluid compartment showing an increase after surgery, and peaked on postoperative day (POD) 2. Twelve patients experienced infectious complications. The peaks of changes in ECW and ECW/TBW appeared earlier and their values at the highest peak were significantly lower in the group without infectious complications on POD 2. The ICW/FFM value showed a mild decrease as compared to POD1 and then gradually recovered. It was significantly lower even before surgery and showed the most significant stratification on POD2. ECW/TBW of 48% and ICW/FFM of 37% on POD2 were predictive cut-off values for infectious adverse events with high area-under receiver operating characteristic (ROC) curves: 0.80 or higher.

CONCLUSION

BIA measurements are useful for monitoring fluid retention and may predict infectious complications in the early phase after transthoracic esophagectomy.

TRIAL REGISTRATION

Registry name: UMIN-CTR, ID: UMIN000030734, Registered on January 9, 2018, retrospectively registered.

Bioelectrical impedance phase angle in sport: a systematic review

BACKGROUND

Phase angle (PhA) is a raw BIA variable that has been gaining attention in recent years because it is supposed to be an index of the ratio between extracellular and intracellular water, body cell mass, and cellular integrity. The aim of this systematic review was to evaluate the variability of PhA between different sports and its relationships with sport performance. Additionally, we investigated whether PhA depends on gender or age, and analyzed the differences between athletes and controls.

METHODS

A systematic research using PubMed, Scopus and Web of Science up to June 2019 was performed. Selection criteria included studies on subjects who practice sports in planned and continuous modality at competitive or elite level.

RESULTS

Thirty-five papers met the inclusion criteria (twenty-one cross-sectional data, fourteen longitudinal data). A few but convincing studies have shown that mean PhA is higher in athletes vs. controls. PhA increases with age and is likely to be higher in male than female athletes. A large variability in PhA is observed for the same sport, while it is still uncertain to what extent PhA differs between various sports. There are no clear relationships of PhA with sport performance or training/untraining.

CONCLUSION

It is still to be defined to what extent PhA varies between different sports and changes with training/untraining. It can be argued that for a given sport much more data should be collected in a systematic way and for a period of time appropriate in order to determine changes and trends. This is even more crucial in the case of intervention studies.

Assessment of bioelectrical phase angle as a predictor of nutritional status in patients with Crohn's disease: A cross sectional study.Clin Nutr. 2020;39:1564-1571. [PMID: 31303525 DOI: 10.1016/j.clnu.2019.06.023]

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.

Impact of serum albumin levels on the body fluid response to tolvaptan in chronic kidney disease patients

PURPOSE

Tolvaptan exerts an aquaretic effect by blocking vasopressin V2 receptor. Although tolvaptan ameliorates body fluid retention even in patients with chronic kidney disease (CKD), predictors of body fluid reduction induced by tolvaptan remain unclear. We, therefore, examined the clinical parameters associated with the effect of tolvaptan on fluid volume in CKD patients.

METHODS

Twelve CKD patients (stage 3-5) with fluid retention were treated with tolvaptan in addition to conventional diuretic treatment. Patients were divided into low and high responders by the median change in total body water (TBW) for 1 week measured by a bioimpedance analysis (BIA) device, and clinical parameters were compared between the groups.

RESULTS

The body weight significantly decreased by 2.0 ± 2.3 kg (p = 0.005), but the estimated glomerular filtration rate (eGFR) was not significantly changed (16.9 ± 11.9 vs. 17.4 ± 12.4 mL/min/1.73 m², p = 0.139) after 1 week. The BIA showed that the intracellular water (ICW) decreased by 6.0% ± 4.7% (p < 0.001), the extracellular water (ECW) decreased by 6.7% ± 5.4% (p = 0.001), and the TBW decreased by 6.3% ± 4.9% (median value - 6.02%, p < 0.001). The serum albumin level in the high responders was significantly lower than in the low responders (2.3 ± 0.5 vs. 3.3 ± 0.8 g/dL, p = 0.013). Significant partial correlations adjusted for the eGFR were observed between the baseline serum albumin level and changes in the ICW (r = 0.440, p = 0.048), ECW (r = 0.593, p = 0.009) and TBW (r = 0.520, p = 0.020).

CONCLUSIONS

Serum albumin levels predict the body fluid response to tolvaptan in CKD patients. Tolvaptan may be a promising therapeutic option for ameliorating body fluid retention, especially in patients with hypoalbuminemia.

Bioimpedance analysis and physical functioning as mortality indicators among older sarcopenic people

OBJECTIVES

To assess the prognostic significance of various characteristics and measurements of sarcopenia and physical functioning on all-cause mortality among home-dwelling older people with or at-risk of sarcopenia.

DESIGN

Cross-sectional and longitudinal analyses.

SETTING

Porvoo sarcopenia trial in open care.

PARTICIPANTS

Community-dwelling people aged 75 and older (N = 428, of which 182 were re-examined at one year) with four years of follow-up.

MEASUREMENTS

Body mass index (BMI), physical functioning (physical component of the RAND-36) and physical performance tests (Short Physical Performance Battery (SPPB)), hand grip strength, walking speed, Charlson Comorbity Index, bioimpedance-based surrogates for muscle mass: Single Frequency Skeletal Muscle Index (SF-SMI), and Calf Intracellular Resistance Skeletal Muscle Index (CRi-SMI). Date of death was retrieved from central registers. Survival analyses were performed using Life-Table analyses and Cox models.

RESULTS

Most test variables (except BMI) were associated with four-year mortality in a dose-dependent fashion. After controlling for age, gender and co-morbidity, physical performance and functioning (both SPPB and RAND-36), muscle strength (hand grip strength) and CRi-SMI appeared to be independent mortality risk indicators (p < 0.001) whereas SF-SMI was not. When CRi-SMI values were grouped by gender-specific cut-off points, the probability of surviving for four years decreased by 66% among the older people with low CRi-SMI (HR = 0.34, 95%CI 0.15-0.78, p = 0.011). When low CRi-SMI was further controlled for SPPB, the prognostic significance remained significant (HR = 0.55, 95%CI 0.33-0.92, p = 0.021). After controlling for age, gender, comorbidity, and CRi-SMI, the physical component of the RAND-36 (p = 0.007), SPPB (p < 0,001) and hand grip strength (p = 0.009) remained significant mortality predictors. Twelve-month changes were similarly associated with all-cause mortality during the follow-up period.

CONCLUSION

CRi-SMI, muscle strength, physical performance and physical functioning are each strong independent predictors of all-cause mortality among home-dwelling older people. Compared to these indicators, BMI seemed to be clearly inferior. Of two bioimpedance-based muscle indices, CRi SMI was better predictor of mortality than SF-SMI. In this regard, muscle mass, muscle strength and physical performance are all suitable targets for the prevention of sarcopenia-related over-mortality.

Predicting Menstrual Recovery in Adolescents With Anorexia Nervosa Using Body Fat Percent Estimated by Bioimpedance Analysis

OBJECTIVE

To identify the threshold of total body fat percentage (TBF%) required for the resumption of menses (ROM) in hospitalized female adolescents with anorexia nervosa (AN) using bioimpedance analysis (BIA).

METHODS

All female adolescents hospitalized with AN in our medical center were evaluated in a longitudinal prospective study during the years of 2012-2017. Anthropometric data, body fat measured by BIA, and hormonal determinants were collected periodically, in addition to routine medical and gynecological assessments.

RESULTS

Sixty-two participants presented with secondary amenorrhea, of which 20 remained with amenorrhea and 42 had ROM during hospitalization. At discharge, participants with ROM regained significantly more weight, and had higher mean body mass index (BMI), BMI standard deviation scores, and TBF% than those who remained with amenorrhea. Receiver operating characteristic analysis identified that a TBF% of 21.2% had the highest discriminative ability for ROM (sensitivity = 88%, specificity = 85%, positive predictive value = 93%). Compared with the anthropometric parameters, TBF% had the highest area under curve (AUC = .895), which significantly differed from that of BMI standard deviation scores (AUC = .643, p = .007) and body weight (AUC = .678, p = .03).

CONCLUSIONS

BIA is a safe and relatively simple method to assess the TBF% required for the return of balanced menstrual cycles in female adolescents with AN. The TBF% with the highest discriminative ability for menstrual resumption as assessed by BIA is 21.2%.

A ketogenic diet exerts beneficial effects on body composition of cancer patients during radiotherapy: An interim analysis of the KETOCOMP study

Background and aim

Ketogenic diets (KDs) have gained interest as a complementary treatment for cancer patients. Here we present first results of our ongoing KETOCOMP study (NCT02516501) concerning body composition changes among rectal, breast and head & neck cancer (HNC) patients who consumed a KD during curative radiotherapy (RT).

Experimental procedure

Sixty-one patients eating a non-ketogenic diet were compared to 20 patients on a KD supplemented with 10 g essential amino acids on RT days. Body composition was measured prior to and weekly during RT using 8-electrode bioimpedance analysis. Longitudinal body composition data were analyzed using linear mixed effects models.

Results and conclusion

Patients on the KD exhibited nutritional ketosis, defined as serum β-hydroxybutyrate levels ≥0.5 mmol/l, in a median of 69.0% of blood measurements (range 0–100%) performed in our clinic. In rectal and breast cancer patients, KD was significantly associated with a loss of 0.5 and 0.4 kg fat mass per week (p = 0.00089 and 8.49 × 10⁻⁵, respectively), with no significant changes in fat free and skeletal muscle mass. In HNC patients, concurrent chemotherapy was the strongest predictor of body weight, fat free and skeletal muscle mass loss during RT, while consuming a KD was significantly associated with a gain in these measures. These preliminary results confirm prior reports indicating that KDs are safe to consume during standard-of-care therapy. They also provide an important first indication that KDs with ample amino acid intake could improve body composition during RT in curative cancer patients.

•

Consumption of a ketogenic diet (KD) during radio(chemo-)therapy is feasible.

•

In rectal and breast cancer patients, the KD significantly reduced fat mass.

•

Fat-free mass and skeletal muscle mass were preserved by the KD.

•

In head and neck cancer patients a KD influenced body composition opposite to chemotherapy.

Improved strength prediction combining clinically available measures of skeletal muscle mass and quality

BACKGROUND

Measures of skeletal muscle function decline at a faster rate with ageing than do indices of skeletal muscle mass. These observations have been attributed to age-related changes in muscle quality, another functional determinant separate from skeletal muscle mass. This study tested the hypothesis that improved predictions of skeletal muscle strength can be accomplished by combining clinically available measures of skeletal muscle mass and quality.

METHODS

The participants included 146 healthy adult (age ≥ 18 years, range 18-77 years; X ± SD 47 ± 17 years and body mass index 16.5-51.8 kg/m2 ; 27.7 ± 6.2 kg/m2 ) men (n = 60) and women (n = 86) in whom skeletal muscle mass was estimated as appendicular lean soft tissue (LST) measured by dual-energy X-ray absorptiometry and skeletal muscle quality as bioimpedance analysis-derived phase angle and B-mode-evaluated echogenicity of mid-thigh skeletal muscle. Strength of the right leg and both arms was quantified as knee isokinetic extension and handgrip strength using dynamometers. The statistical significance of adding phase angle or echogenicity to strength prediction multiple regression models that included extremity-specific LST and other covariates (e.g. age and sex) was evaluated to test the study hypothesis.

RESULTS

Right leg LST mass alone was significantly (P < 0.0001) correlated with isokinetic right leg strength (R2  = 0.57). The addition of segmental phase angle measured in the right leg at 50 kHz increased the R2 of this model to 0.66 (P < 0.0001); other phase angle frequencies (5 and 250 kHz) did not contribute significantly to these models. Results were similar for both right and left arm handgrip strength prediction models. Adding age and sex as model covariates increased the R2 values of these models further (e.g. right leg strength model R2 increased to 0.71), but phase angle continued to remain a significant (all P < 0.01) predictor of extremity strength. Similarly, when predicting isokinetic right leg strength, mid-thigh skeletal muscle echogenicity added significantly (P < 0.0001) to right leg LST, increasing R2 from 0.57 to 0.64; age was a significant (P < 0.0001) covariate in this model, increasing R2 further to 0.68.

CONCLUSIONS

The hypothesis of the current study was confirmed, strongly supporting and extending earlier reports by quantifying the combined independent effects of skeletal muscle mass and quality on lower-body and upper-body measures of strength. These observations provide a clinically available method for future research aimed at optimizing sarcopenia and frailty risk prediction models.

Sarcopenia Indicators as Predictors of Functional Decline and Need for Care among Older People

OBJECTIVES

Sarcopenia is associated with poor health outcomes. We examined the relative roles of muscle mass, strength, physical performance and obesity as health predictors among older sarcopenic people.

DESIGN AND PARTICIPANTS

This prospective study examined community-dwelling people aged 75+ (N=262).

SETTING

Porvoo Sarcopenia and Nutrition Trial.

MEASUREMENTS

We collected demographic data and medical history by postal questionnaire including RAND-36 at baseline and at four years and measured BMI, Short Physical Performace Battery (SPPB), hand-grip strength, cognition and two surrogate measures of muscle mass; the Single Frequency Skeletal Muscle Index (SF-SMI) and the Calf Intracellular Resistance Skeletal Muscle Index (CRi-SMI).

RESULTS

Adjusted for age and gender, independent outdoors mobility was predicted positively by baseline physical functioning scores in RAND-36 (p<0.001), the SPPB (p<0.001), the two-minute step test (p<0.001), and grip strength (p=0.023), as well as CRi-SMI (p<0.001). However, the prediction was negative in BMI (p<0.001) and the Charlson co-morbidity Index (p= 0.004). Similar associations were found when the physical component RAND-36 was used as an outcome measure. The use of home care was predicted by high co-morbidity (p=0.057) and low scores in RAND-36 (p<0.001), SPPB (p<0.001) and the two-minute step test (p<0.001), and low CRi-SMI (p<0.001). CRi-SF was a more consistent predictor than SF-SMI, which was partly masked by BMI. Controlled for age, gender and comorbidity, a 10% difference in CRi-SMI was associated with a 4% higher probability (p=0.019) of independently living at home, whereas the respective figures for SF-SMI and BMI were -18% (p=0.098) and -14% (p=0.088).

CONCLUSIONS

In contrast to SF-SMI, high CRi-SMI appeared to indicate good prognosis and less need of care, independently of BMI.