Measuring body composition in chronic heart failure: A comparison of methods

Population pharmacokinetics of ramipril in patients with chronic heart failure: A real-world longitudinal study

In patients with chronic heart failure (CHF), the use of angiotensin-converting enzyme inhibitors, including ramipril, is recommended to reduce the risk of heart failure worsening, hospitalisation, and death. Our aim was to investigate the influence of body composition on the pharmacokinetics of ramipril and its active metabolite ramiprilat and to evaluate the changes in pharmacokinetics after prolonged therapy. Twenty-three patients with CHF who were on regular therapy with ramipril participated at the first study visit ( median age 77 years, 65 % male, and 70 % New York Heart Association Class II); 19 patients attended the second study visit and the median time between the two visits was 8 months. Pharmacokinetics were assessed using a nonlinear mixed-effects parent-metabolite model comprising two compartments for ramipril and one compartment for ramiprilat. The influence of body size and composition was best described by an allometric relationship with fat-free mass. In addition, ramipril clearance was related to patient age and daily ramipril dose, while clearance of ramiprilat was influenced by glome rular filtration rate and daily ramipril dose. There were no clinically relevant changes in the pharmacokinetics of ramipril and ramiprilat between the study visits. Due to the relatively stable pharmacokinetics of ramipril, regular outpatient visits at 6-month intervals seem appropriate to evaluate ramipril therapy.

Evaluating Nutritional Risk Factors for Delirium in Intensive-Care-Unit Patients: Present Insights and Prospects for Future Research

Malnutrition, hypercatabolism, and metabolic changes are well-established risk factors for delirium in critically ill patients. Although the exact mechanisms are not fully understood, there is mounting evidence suggesting that malnutrition can cause a variety of changes that contribute to delirium, such as electrolyte imbalances, immune dysfunction, and alterations in drug metabolism. Therefore, a comprehensive metabolic and malnutrition assessment, along with appropriate nutritional support, may help to prevent or ameliorate malnutrition, reduce hypercatabolism, and improve overall physiological function, ultimately lowering the risk of delirium. For this aim, bioelectrical impedance analysis can represent a valuable strategy. Further research into the underlying mechanisms and nutritional risk factors for delirium is crucial to developing more effective prevention strategies. Understanding these processes will allow clinicians to personalize treatment plans for individual patients, leading to improved outcomes and quality of life in the intensive-care-unit survivors.

Skeletal Muscle Mass Recovery Early After Left Ventricular Assist Device Implantation in Patients With Advanced Systolic Heart Failure

BACKGROUND

Patients with advanced systolic heart failure are at risk of unintentional weight loss and muscle wasting. It has been observed that left ventricular assist device (LVAD) recipients gain weight after device implantation, although it is unknown whether this represents skeletal muscle mass gains. We aimed to determine whether skeletal muscle mass increases early during LVAD support.

METHODS

We prospectively recruited 30 adults with systolic heart failure ±21 days from LVAD implantation. Participants underwent whole-body dual X-ray absorptiometry to measure fat free mass, appendicular lean mass (ALM, lean mass in the arms and legs) and fat mass. Dual X-ray absorptiometry imaging was repeated at 3 and 6 months after LVAD implantation, with participation ending after the 6-month visit or heart transplantation, whichever occurred first. Changes in body composition were evaluated using mixed effects linear regression models.

RESULTS

The cohort was 87% male, with mean age 56±12 (SD) years, and mean body mass index 26.4±5.4 kg/m2. Per sarcopenia ALM criteria, 52% of participants had muscle wasting at baseline. At baseline, mean fat free mass and ALM were 56.4±11.7 and 21.0±5.3 kg, respectively. Both measures increased significantly (P<0.001) over 6 months of LVAD support: mean fat free mass change at 3 and 6 months: 2.3 kg (95% CI, 1.0-3.5) and 4.2 kg (95% CI, 2.2-6.1); mean ALM change at 3 and 6 months: 1.5 kg (95% CI, 0.7-2.3) and 2.3 kg (95% CI, 0.9-3.6).

CONCLUSIONS

Among LVAD recipients with advanced systolic heart failure and high baseline prevalence of muscle wasting, there were significant gains in skeletal muscle mass, as represented by dual X-ray absorptiometry fat free mass and ALM, over the first 6 months of LVAD support.

The impact of hydration status and fluid distribution on pulmonary function in COPD patients

Chronic Obstructive Pulmonary Disease (COPD) patients have alterations in body composition. Bioelectrical impedance analysis (BIA) evaluates body composition, hydration status, and fluid distribution. Subjects with fluid disturbances have been found to have lower FEV1, respiratory muscle strength, and poor prognosis. We aimed to evaluate the effect of hydration status and fluid distribution on pulmonary function in COPD patients. A cross-sectional study, 180 patients with a confirmed diagnosis of COPD were included. Patients with asthma, advanced renal or liver disease, acute HF, exacerbation of COPD, or pacemakers were excluded. Hydration status variables (TBW, ECW, ICW) and disturbance of fluid distribution [impedance ratio (IR) > 0.84 and phase angle (PhA)] were evaluated by BIA. Pulmonary function was assessed by spirometry. The mean population age was 71.55 ± 8.94 years; 55% were men. Subjects were divided into two groups according to the IR ≥ 0.84 or < 0.84. The group with higher IR ≥ 0.84 had lower FEV1, FVC, FEV1/FVC, DLCO and, PhA compared to those with IR < 0.84. After adjusting for confounding variables TBW, ECW, IR ≥ 0.84, PhA, and resistance/height increase were associated with decreased FEV1. In the same way, with IR ≥ 0.84, edema index ≥ 0.48, trunk and abdominal IR were negatively associated with FVC, and PhA had a positive association with FVC. Fluid distribution, especially IR and PhA, could be a useful parameter for predicting pulmonary function in COPD patients.

Sarcopenia in cardiac surgery: Dual X-ray absorptiometry study from the McGill frailty registry

BACKGROUND

To determine the prevalence and prognostic value of sarcopenia measured by dual x-ray absorptiometry (DXA) and physical performance tests in patients undergoing coronary artery bypass surgery or heart valve procedures.

METHODS

Adults undergoing cardiac surgery were prospectively enrolled and completed a questionnaire, physical performance battery, and a DXA scan (GE Lunar) to measure appendicular muscle mass indexed to height² (AMMI). Patients were categorized as sarcopenic based on European Working Group 2 guidelines if they had low AMMI defined as <7 kg/m² for men or <5.5 kg/m² for women, and low muscle strength defined as 5 chair rise time ≥15 seconds. Cox proportional hazards regression was used to test the association between sarcopenia and all-cause mortality over a median follow-up of 4.3 years.

RESULTS

The cohort consisted of 141 patients with a mean age of 69.7 ± 10.0 years and 21% females. The prevalence rates of low AMMI, slow chair rise time, and sarcopenia (low AMMI and slow chair rise time) were 24%, 57%, 13%, respectively. The 4-year survival rate was 79% in the non-sarcopenic group as compared to 56% in the sarcopenic group (Log-rank P = 0.01). In the multivariable model, each standard deviation of decreasing AMMI and increasing chair rise time was associated with a hazard ratio for all-cause mortality of 1.84 (95% CI 1.18, 2.86) and 1.79 (95% CI 1.26, 2.54), respectively.

CONCLUSION

Lower-extremity muscle strength and DXA-based muscle mass are objective indicators of sarcopenia that are independently predictive of all-cause mortality in older cardiac surgery patients.

Associations of Skeletal Muscle Mass and Fat Mass With Incident Cardiovascular Disease and All-Cause Mortality: A Prospective Cohort Study of UK Biobank Participants

Background There is debate whether body mass index is a good predictor of health outcomes because different tissues, namely skeletal muscle mass (SMM) and fat mass (FM), may be differentially associated with risk. We investigated the association of appendicular SMM (aSMM) and FM with fatal and nonfatal cardiovascular disease (CVD) and all-cause mortality. We compared their prognostic value to that of body mass index. Methods and Results We studied 356 590 UK Biobank participants aged 40 to 69 years with bioimpedance analysis data for whole-body FM and predicted limb muscle mass (to calculate aSMM). Associations between aSMM and FM with CVD and all-cause mortality were examined using multivariable Cox proportional hazards models. Over 3 749 501 person-years of follow-up, there were 27 784 CVD events and 15 844 all-cause deaths. In men, aSMM was positively associated with CVD incidence (hazard ratio [HR] per 1 SD 1.07; 95% CI, 1.06-1.09) and there was a curvilinear association in women. There were stronger positive associations between FM and CVD with HRs per SD of 1.20 (95% CI, 1.19-1.22) and 1.25 (95% CI, 1.23-1.27) in men and women respectively. Within FM tertiles, the associations between aSMM and CVD risk largely persisted. There were J-shaped associations between aSMM and FM with all-cause mortality in both sexes. Body mass index was modestly better at discriminating CVD risk. Conclusions FM showed a strong positive association with CVD risk. The relationship of aSMM with CVD risk differed between sexes, and potential mechanisms need further investigation. Body fat and SMM bioimpedance measurements were not superior to body mass index in predicting population-level CVD incidence or all-cause mortality.

Bioimpedance vector analysis in stable chronic heart failure patients: Level of agreement between single and multiple frequency devices

BACKGROUND & AIMS

The accuracy of estimating body composition compartments is critical in the clinical setting. Currently, there are different bioelectrical impedance analysis (BIA) devices available for obtaining raw BIA parameters. The aim of this study was to determine the level of agreement between multiple frequency (MF)-BIA and single frequency (SF)-BIA devices in obtaining raw BIA measurements (resistance (R), reactance (Xc), and phase angle (PhA)), as well as the agreement on the classification of hydration status and body cell mass by the bioelectrical impedance vector analysis (BIVA) method.

METHODS

This cross-sectional study included 406 outpatients with stable chronic heart failure (HF). The raw BIA measurements at 50 kHz obtained by tetrapolar MF-BIA (Bodystat QuadScan 4000) were compared with those obtained by tetrapolar SF-BIA (RJL Quantum X). In addition, the patients were classified by their hydration status and body cell mass according to the BIVA method.

RESULTS

Strong and significant correlations were observed between the two methods in all raw BIA variables (r ≥ 0.90). Lin's concordance correlation coefficient (CCC) values were almost perfect for R (CCC = 0.99; 95% CI 0.997 to 0.998), moderate for Xc (CCC = 0.93; 95% CI 0.92 to 0.94), and poor for PhA (CCC = 0.88; 95% CI 0.85 to 0.90). The agreement obtained in the two classifications (quadrants and hydration status) was >0.81.

CONCLUSIONS

MF-BIA and SF-BIA demonstrated good agreement for measurement of the R parameter; however, the Xc and PhA parameters must be used carefully due to the previously reported variability. Likewise, the agreement in all classifications by the BIVA method was almost perfect.

Fluid Status After Cardiac Surgery Assessed by Bioelectrical Impedance Vector Analysis and the Effects of Extracorporeal Circulation

OBJECTIVE

Hydration status after cardiac surgery can be difficult to assess, often requiring invasive measurements. Bioelectrical impedance vector analysis (BIVA) is based on patterns of resistance (R) and reactance (Xc), corrected by height, and has been used in various clinical scenarios to determine body composition and monitor its changes over time. The purpose of the present study was to apply this method in cardiac surgery patients to assess the variation in hydration status and to compare its changes according to the use of extracorporeal circulation.

DESIGN

Single-center, observational, prospective study including patients older than 18 years undergoing elective or urgent cardiac surgery.

SETTING

Intensive cardiac care unit of a tertiary center in a metropolitan area.

PARTICIPANTS

The study comprised 76 patients with a median age of 60 years and mostly undergoing coronary artery bypass grafting (CABG) (n = 47 [61.8%]) with extracorporeal circulation (n = 54 [73%]).

INTERVENTIONS

Bioimpedance was measured with a standard tetrapolar single-frequency bioimpedance meter using a standardized procedure and plotted in an R-Xc graph.

MEASUREMENTS AND MAIN RESULTS

The study demonstrated an increase in total body water immediately after surgery that was sustained until producing hyperhydration 24 hours later. Off-pump CABG was associated with a normal hydration status after surgery, whereas on-pump CABG produced a significant increase in total body water.

CONCLUSIONS

Fluid status assessment with BIVA in cardiac surgery showed an increase in total body water up to 24 hours after surgery. Off-pump surgery prevented overhydration, which partially could explain the reduction in some of the postoperative complications. BIVA could serve as a useful method for monitoring fluid status in the setting of goal-directed therapy to assist in maintaining euvolemia in cardiac surgical patients.

Association between adherence to MIND diet and general and abdominal obesity: a cross-sectional study

BACKGROUND

Recently, a new eating pattern called as "Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND)" has been coined. Emerging studies are examining this dietary pattern with chronic conditions. We aimed to investigate the association between the MIND diet score and general and central obesity among adults.

METHODS

This cross-sectional study was conducted in a framework of the Study on the Epidemiology of Psychological Alimentary Health and Nutrition (SEPAHAN). Dietary information was collected using a validated self-administered 106-item Willett-format dish-based semi-quantitative food frequency questionnaire (DS-FFQ) in 6724 adults. Adherence to the MIND diet was examined based on components suggested in this eating pattern. Anthropometrics data were collected using a validated self-reported questionnaire. General obesity was defined as body mass index ≥30 kg/m2, and abdominal obesity as waist circumference > 102 cm for men and > 88 cm for women.

RESULTS

Mean age, BMI and WC in the study population was 36.8 ± 8.08 y, 24.9 ± 3.8 kg/m2 and 83.7 ± 16.02 cm, respectively. Overall, 9.5% of subjects were generally obese and 24.4 were abdominally obese. Examining the whole study population, we found no significant association between the MIND diet score and odds of general obesity, either before (ORs for comparing T3 vs. T1: 1.03; 95% CI: 0.83, 1.27; P-trend = 0.74) or after controlling for potential confounders (ORs for T3 vs. T1: 0.91; 95% CI: 0.67, 1.25; P-trend = 0.58). This was also the case for men and women when analyzed separately. We also failed to find any significant association between the MIND diet score and odds of abdominal obesity after controlling for potential confounders in the whole study population (ORs for T3 vs. T1: 1.00, 95% CI: 0.79, 1.27; P-trend = 0.87). However, women with the greatest adherence to the MIND diet were 19% less likely to be abdominally obese than those with the lowest adherence in crude model (OR = 0.81; 95% CIs: 0.67, 0.98; P-trend = 0.03). This association disappeared after controlling for potential confounders (OR = 0.87; 95% CIs: 0.66, 1.14; P-trend = 0.55).

CONCLUSION

No significant association was observed between adherence to the MIND diet and odds of general and central obesity.

Effectiveness of combined eccentric and concentric exercise over traditional cardiac exercise rehabilitation programme in patients with chronic heart failure: protocol for a randomised controlled study

INTRODUCTION

Exercise-based rehabilitation is a standard feature of chronic heart failure management. The effectiveness of eccentric exercise could offer new opportunities for better tailoring rehabilitation programme to patients' limitations. The goal of the study is to contrast the impact of a mixed eccentric and concentric cycling training programme, to that of conventional concentric cycling rehabilitation in patients with chronic heart failure (peak oxygen consumption (VO_2Peak) < 15 mL⋅kg^-1⋅min^-1, ejection fraction <40%).

METHODS AND ANALYSIS

It is a prospective, open, controlled and randomised study (2×25 subjects) carried out in a single centre. Subjects will perform five exercise sessions per week per the randomisation outcome, with the intervention group performing eccentric in three of the five weekly sessions while the control group will perform the five sessions of concentric exercise. Cycling intensity will be the same in both groups and fixed to the power associated with the first ventilatory threshold. Self-management education programme, callisthenics sessions and muscle strength trainings will also be carried out as for any heart failure patient normally included in the rehabilitation programme. The primary outcome will be the change in distance covered during the 6 min walk test. Secondary outcomes will include other physical mobility parameters, functional exercise capacities, quality of life and body composition as well as skeletal muscle properties including mitochondrial function parameters.

ETHICS AND DISSEMINATION

The study has been approved by the institutional ethics review board (17.079) and the French regulatory authority for research (2017-A00969-44). Adverse events that could occur during the protocol will be reported to the principal investigator. The results will be published in an international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03716778.

Body composition changes assessment by bioelectrical impedance vectorial analysis in right heart failure and left heart failure

BACKGROUND

Heart Failure (HF) patients developed changes in body composition as overhydration, muscle-skeletal wear and cardiac cachexia (CC). The possible factors involved in the development of CC in Right Heart Failure (RHF) patients are venous congestion, nutrient malabsorption. However, in HF, the overhydration obscure the loss of fat-free mass and difficult the body composition assessment. Bioelectrical impedance vectorial analysis (BIVA) is a method validated and used for hydration status and body composition assessment in HF. The aim of this study was to investigate the body compositions changes assessment by BIVA in the subjects with and without RHF and evaluate the risk factors for devolvement CC in HF subjects.

MATERIAL AND METHODS

Prospective cohort study. Subjects with confirmed diagnoses of HF, >18 years old without CC according to BIVA criteria were included. Subjects with congenital heart disease, cancer, HIV, and end-stage renal disease were excluded. Body composition was an assessment by BIVA. 288 HF patients were evaluated. RHF subjects had an impedance vector reduction (9.26 dR/H and -1.92 dXc/H, T2=14.9, D = 0.45, p<0.001), while subjects without RHF no-showed statistically significant changes (7.57 dR/H and 0.72 dXc/H, T2=3, D = 0.17, p = 0.200). The risks factors to development CC were age, RHF, phase angle < 5°, total body water were risks factors while handgrip strength was a protector factor.

CONCLUSIONS

RHF has greater disturbances in body composition and is a risk factor to development CC.

Fluid management in acute kidney injury

Acute kidney injury (AKI) and fluids are closely linked through oliguria, which is a marker of the former and a trigger for administration of the latter. Recent progress in this field has challenged the physiological and clinical rational of using oliguria as a trigger for the administration of fluid and brought attention to the delicate balance between benefits and harms of different aspects of fluid management in critically ill patients, in particular those with AKI. This narrative review addresses various aspects of fluid management in AKI outlining physiological aspects, the effects of crystalloids and colloids on kidney function and the effect of various resuscitation and de-resuscitation strategies on the course and outcome of AKI.

Frequency of fluid overload and usefulness of bioimpedance in patients requiring intensive care for sepsis syndromes

Guideline-directed therapy for sepsis calls for early fluid resuscitation. Often patients receive large volumes of intravenous fluids. Bioimpedance vector analysis (BIVA) is a noninvasive technique useful for measuring total body water. In this prospective observational study, we enrolled 18 patients admitted to the intensive care unit for the treatment of sepsis syndromes. Laboratory data, clinical parameters, and BIVA were recorded daily. All but one patient experienced volume overload during the course of treatment. Two patients had >20 L of excess volume. Volume overload is clinically represented by tissue edema. Edema is not a benign condition, as it impairs tissue oxygenation, obstructs capillary blood flow, disrupts metabolite clearance, and alters cell-to-cell interactions. Specifically, volume overload has been shown to impair pulmonary, cardiac, and renal function. A positive fluid balance is a predictor of hospital mortality. As septic patients recover, volume excess should be aggressively treated with the use of targeted diuretics and renal replacement therapies if necessary.

Bioelectrical impedance vector analysis in critically ill patients: a prospective, clinician-blinded investigation

Introduction

Assessment of fluid status in critically ill patients is challenging. We aimed to assess the feasibility and validity of bioelectrical impedance vector analysis (BIVA) as a measure of hydration in critically ill patients.

Methods

We performed twice-daily BIVA measurements and fluid balance calculations and recorded physiological variables in mechanically ventilated patients within 24 h of intensive care unit (ICU) admission for up to 5 days. Treating clinicians were blinded to BIVA results.

Results

We performed 344 BIVA measurements in 61 patients. According to BIVA, 14 patients (23 %) were dehydrated, 22 (36 %) were normally hydrated and 25 (41 %) were overhydrated upon ICU admission. Patients with normal BIVA hydration were less sick, had fewer comorbidities and had less deranged physiology than patients found to be dehydrated or overhydrated with BIVA. Cumulative fluid balance increased in patients found to be dehydrated with BIVA by a mean of 3.4±2.2 L, whereas in patients found to be overhydrated with BIVA, it decreased by a mean of 4.5±6.9 L. In patients found to be normally hydrated with BIVA, fluid balance remained unchanged. BIVA-defined hydration increased with 1 L (median change 1.5 %, P =0.09) or 2 L (median change 0.7 %, P =0.09) of calculated fluid gains. BIVA-defined hydration decreased (median change −0.8 %, P =0.02) with a negative cumulative fluid balance of >2 L. BIVA-defined hydration between first and last measurement correlated with the corresponding change in fluid balance (ρ =0.25, P =0.05).

Conclusions

BIVA is feasible in critically ill patients. Its validity is supported by the observed characteristics of patients with different degrees of BIVA hydration upon admission and by different fluid management of such patients by blinded clinicians. The sensitivity of repeated BIVA hydration measurements to detect fluid accumulation or fluid balance changes <2 L was low, however. These contradictory findings provide the rational basis for studies of BIVA-assisted fluid management in ICU patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-1009-3) contains supplementary material, which is available to authorized users.

Fluid Overload

Most critically ill patients experience external or internal fluid shifts and hemodynamic instability. In response to these changes, intravenous fluids are frequently administered. However, rapid losses of administered fluids from circulation and the indirect link between the short-lived plasma volume expansion and end points frequently result in transient responses to fluid therapy. Therefore, fluid overload is a common finding in intensive care units. The authors consider the evidence of harm associated with fluid overload and the physiologic processes that lead to fluid accumulation in critical illness. The authors then consider methods to prevent fluid accumulation and/or manage its resolution.

Skeletal muscle abnormalities in pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension is a progressive disease that is characterized by dyspnea and exercise intolerance. Impairment in skeletal muscle has recently been described in PAH, although the degree to which this impairment is solely determined by the hemodynamic profile remains uncertain. The aim of this study was to verify the association of structural and functional skeletal muscle characteristics with maximum exercise in PAH.

METHODS

The exercise capacity, body composition, CT area of limb muscle, quality of life, quadriceps biopsy and hemodynamics of 16 PAH patients were compared with those of 10 controls.

RESULTS

PAH patients had a significantly poorer quality of life, reduced percentage of lean body mass, reduced respiratory muscle strength, reduced resistance and strength of quadriceps and increased functional limitation at 6MWT and CPET. VO2 max was correlated with muscular variables and cardiac output. Bivariate linear regression models showed that the association between muscular structural and functional variables remained significant even after correcting for cardiac output.

CONCLUSION

Our study showed the coexistence of ventilatory and quadriceps weakness in face of exercise intolerance in the same group of PAH patients. More interestingly, it is the first time that the independent association between muscular pattern and maximum exercise capacity is evidenced in PAH, independently of cardiac index highlighting the importance of considering rehabilitation in the treatment strategy for PAH.

Indications and management of mechanical fluid removal in critical illness

BACKGROUND

The Acute Dialysis Quality Initiative (ADQI) dedicated its Twelfth Consensus Conference (2013) to all aspects of fluid therapy, including the management of fluid overload (FO). The aim of the working subgroup 'Mechanical fluid removal' was to review the indications, prescription, and management of mechanical fluid removal within the broad context of fluid management of critically ill patients.

METHODS

The working group developed a list of preliminary questions and objectives and performed a modified Delphi analysis of the existing literature. Relevant studies were identified through a literature search using the MEDLINE database and bibliographies of relevant research and review articles.

RESULTS

After review of the existing literature, the group agreed the following consensus statements: (i) in critically ill patients with FO and with failure of or inadequate response to pharmacological therapy, mechanical fluid removal should be considered as a therapy to optimize fluid balance. (ii) When using mechanical fluid removal or management, targets for rate of fluid removal and net fluid removal should be based upon the overall fluid balance of the patient and also physiological variables, individualized, and reassessed frequently. (iii) More research on the role and practice of mechanical fluid removal in critically ill patients not meeting fluid balance goals (including in children) is necessary.

CONCLUSION

Mechanical fluid removal should be considered as a therapy for FO, but more research is necessary to determine its exact role and clinical application.

New reference values for body composition by bioelectrical impedance analysis in the general population: results from the UK Biobank

BACKGROUND

Low fat-free mass (FFM) is a risk factor for morbidity and mortality in elderly and patient populations. Therefore, measurement of FFM is important in nutritional assessment. Bioelectrical impedance analysis (BIA) is a convenient method to assess FFM and FFM index (FFMI; FFM/height(2)). Although reference values have been established for individuals with normal body weight, no specific cutoff values are available for overweight and obese populations. Also, limited studies accounted for the age-related decline in FFM.

OBJECTIVE

To determine BMI- and age-specific reference values for abnormal low FFM(I) in white-ethnic men and women free of self-reported disease from the general population.

DESIGN

The UK Biobank is a prospective epidemiological study of the general population from the United Kingdom. Individuals in the age category 45 to 69 years were analyzed. In addition to body weight, FFM and FFMI were measured using a Tanita BC-418MA. Also, self-reported chronic conditions and ethnic background were registered, and lung function was assessed using spirometry.

RESULTS

After exclusion of all individuals with missing data, nonwhite ethnicity, self-reported disease, body mass index (BMI) less than 14 or 36 kg/m(2) or higher, and/or an obstructive lung function, reference values for FFM and FFMI were derived from 186,975 individuals (45.9% men; age: 56.9 ± 6.8 years; BMI: 26.5 ± 3.6 kg/m(2); FFMI 18.3 ± 2.4 kg/m(2)). FFM and FFMI were significantly associated with BMI and decreased with age. Percentiles 5, 10, 25, 50, 75, 90, and 95 were calculated for FFM, FFMI, and fat mass (index), after stratification for gender, age, and BMI.

CONCLUSIONS

Using the UK Biobank dataset, new reference values for body composition assessed with BIA were determined in white-ethnic men and women aged 45 to 69 years. Because these reference values are BMI specific, they are of broad interest for overweight and obese populations.

Sarcopenic obesity is associated with adverse clinical outcome after cardiac surgery

BACKGROUND & AIMS

Both undernutrition - low fat free mass (FFM) - and obesity - high fat mass (FM) - have been associated with adverse outcome in cardiac surgical patients. However, whether there is an additional effect on outcome of these risk factors present at the same time, that is sarcopenic obesity (SO), is unknown. Furthermore, the association between SO and muscle function is unidentified.

METHODS AND RESULTS

In 325 cardiac surgical patients, we prospectively analysed the association between preoperative FFM and FM, measured by bioelectrical impedance spectroscopy, and postoperative adverse outcomes, and their correlation with muscle function - handgrip strength (HGS). SO was associated with postoperative infections (28.2% vs. 5.3%, adj. odds ratio (OR): 7.9; 95% confidence interval (CI): 1.2-54.1; p=0.04). Further, a low FFM index (FFMI; kgm(-2)) was associated with postoperative infections (18.5% vs. 4.7%, adj. OR: 6.6; 95% CI: 1.7-25.2; p=0.01) while a high FM index (FMI; kgm(-2)) was not. Both components of SO, FFMI and FMI, correlated with HGS (FFMI: r=0.570; p<0.001, FMI: r=-0.263; p<0.001).

CONCLUSION

SO is associated with an increased occurrence of adverse outcome after cardiac surgery. Our results suggest an additional risk of a low FFMI and high FMI present at the same time. Furthermore, SO is characterised by less muscle function. We advocate determining body composition in cardiac surgical patients to classify and treat undernourished patients, in particular those who are also obese.

Assessment of intravascular volume status and volume responsiveness in critically ill patients

Accurate assessment of a patient's volume status, as well as whether they will respond to a fluid challenge with an increase in cardiac output, is a critical task in the care of critically ill patients. Despite this, most decisions regarding fluid therapy are made either empirically or with limited and poor data. Given recent data highlighting the negative impact of either inadequate or overaggressive fluid therapy, understanding the tools and techniques available for accurate volume assessment is critical. This review highlights both static and dynamic methods that can be utilized to help in the assessment of volume status.

Capacidade de exercício e seu valor prognóstico no pós-operatório de cirurgia cardíaca

INTRODUÇÃO: O valor prognóstico da capacidade de exercício em pacientes submetidos à cirurgia de revascularização miocárdica (CRM) necessita de esclarecimentos. OBJETIVOS: Avaliar a capacidade de exercício e o seu valor prognóstico em pacientes com doença arterial coronariana, submetidos à cirurgia de revascularização miocárdica eletiva. MATERIAIS E MÉTODOS: Foram avaliados 21 pacientes e 29 controles. Dois incremental shuttle walk test (ISWT) e dois testes de caminhada de 6 min (TC6) foram realizados randomicamente em dias alternados. A força de preensão manual (FPM) foi também avaliada. RESULTADOS: A FPM em valores percentuais (78,4 ± 16 vs. 97,2 ± 15%), o TC6 em metros (412 ± 79 vs. 601 ± 7 m) e em valores percentuais (72 ± 13 vs. 110 ± 11%) e o ISWT em metros (257 ± 90 vs. 517 ± 138 m) e em valores percentuais (53 ± 16 vs. 108 ± 16%) foram significativamente (p < 0,05) inferiores nos pacientes. Onze pacientes apresentaram complicações pós-operatórias (grupo C) e dez evoluíram bem (grupo SC). O grupo C apresentou idade mais avançada (57 ± 6 vs. 71 ± 7 anos; p < 0,05), FPM inferior (33 ± 6 vs. 41 ± 9 kgf) e ISWT inferior (208 ± 81 vs. 311 ± 66 m). Não houve diferenças significativas para o TC6. A regressão logística selecionou o ISWT como determinante do prognóstico dos pacientes (p = 0,04). CONCLUSÃO: Os pacientes à espera de CRM eletiva apresentam significativa redução da capacidade de exercício e o ISWT apresentou valor prognóstico significativo discriminando os pacientes com complicações pós-operatórias.

Is bioelectrical impedance spectroscopy accurate in estimating changes in fat-free mass in judo athletes?

Bioelectrical impedance spectroscopy (BIS) provides an affordable and practical assessment of fat-free mass (FFM). However, little information is available on the assessment of changes in fat-free mass in top-level athletes using BIS. The aim of this study was to examine the accuracy of BIS in tracking changes in fat-free mass of elite male judo athletes from a period of weight stability to just before competition, using the four-compartment model (4C model) as reference method. In total, 27 elite male judo athletes (age 22.2 ± 2.8 years) were evaluated. Measures of body volume assessed by air displacement plethysmography, bone mineral content by dual-energy X-ray absorptiometry, and total-body water assessed with deuterium dilution were used in a 4C model. Fat-free mass was also assessed by BIS (FFM(BIS)). Changes in FFM(BIS) were not significantly different from measured by the reference method (P = 0.000). Furthermore, the r² was 0.62 and the standard error of the estimate was 1.03 kg. The limits of agreement ranged from -3.36 to 2.59 kg with no bias observed. These findings demonstrate the viability of BIS as a valid tool for tracking fat-free mass in elite male judo athletes. However, based on the wide limits of agreement observed, BIS is less valid at an individual level for tracking fat-free mass in these athletes.

Accuracy of quick and easy undernutrition screening tools--Short Nutritional Assessment Questionnaire, Malnutrition Universal Screening Tool, and modified Malnutrition Universal Screening Tool--in patients undergoing cardiac surgery

The objective of this study was to compare the quick-and-easy undernutrition screening tools, ie, Short Nutritional Assessment Questionnaire and Malnutrition Universal Screening Tool, in patients undergoing cardiac surgery with respect to their accuracy in detecting undernutrition measured by a low-fat free mass index (FFMI; calculated as kg/m(2)), and secondly, to assess their association with postoperative adverse outcomes. Between February 2008 and December 2009, a single-center observational cohort study was performed (n=325). A low FFMI was set at ≤14.6 in women and ≤16.7 in men measured using bioelectrical impedance spectroscopy. To compare the accuracy of the Malnutrition Universal Screening Tool and Short Nutritional Assessment Questionnaire in detecting low FFMI sensitivity, specificity, and other accuracy test characteristics were calculated. The associations between the Malnutrition Universal Screening Tool and Short Nutritional Assessment Questionnaire and adverse outcomes were analyzed using logistic regression analyses with odds ratios and 95% confidence intervals (CI) presented. Sensitivity and receiver operator characteristic-based area under the curve to detect low FFMI were 59% and 19%, and 0.71 (95% CI: 0.60 to 0.82) and 0.56 (95% CI: 0.44 to 0.68) for the Malnutrition Universal Screening Tool and Short Nutritional Assessment Questionnaire, respectively. Accuracy of the Malnutrition Universal Screening Tool improved when age and sex were added to the nutritional screening process (sensitivity 74%, area under the curve: 0.72 [95% CI: 0.62 to 0.82]). This modified version of the Malnutrition Universal Screening Tool, but not the original Malnutrition Universal Screening Tool or Short Nutritional Assessment Questionnaire, was associated with prolonged intensive care unit and hospital stay (odds ratio: 2.1, 95% CI: 1.3 to 3.4; odds ratio: 1.6, 95% CI: 1.0 to 2.7). The accuracy to detect a low FFMI was considerably higher for the Malnutrition Universal Screening Tool than for the Short Nutritional Assessment Questionnaire, although still marginal. Further research to evaluate the modified version of the Malnutrition Universal Screening Tool, ie, the cardiac surgery-specific Malnutrition Universal Screening Tool, is needed prior to implementing.

Long-term impact of infantile short bowel syndrome on nutritional status and growth

Short-term bowel adaptation has been documented, but data on long-term effects are scarce. The aim of the present study was to evaluate the long-term consequences of infantile short bowel syndrome (SBS). A cross-sectional assessment (2005–7) of growth, nutritional status, defecation pattern and health status in individuals with a history of infantile SBS, born between 1975 and 2002, were performed. Data were compared with reference values of healthy controls and presented as means and standard deviations or median and ranges. A total of forty subjects (sixteen male and twenty-four female; mean age 14·8 (sd 6·8) years) had received parenteral nutrition during a median of 110 (range 43–2345) d, following small bowel resection. The mean standard deviation scores (SDS) for weight for height and target height (TH) of the children were normal; mean SDS for height for age was − 0·9 (sd 1·3). The median BMI adults was 19·9 (range 17–26) kg/m2; mean SDS for height for age was − 1·0 (range − 2·5 to 1·5). Height in general was significantly shorter than TH, and 53 % of children and 78 % of adults were below TH range. Most subjects had normal body fat percentage (%BF). SDS for total body bone mineral density were generally normal. The SDS for bone mineral content (BMC) of the children were − 1·0 (sd 1·1). Mean energy intake was 91 % of the estimated average requirements. The frequencies of defecation and bowel complaints of the subjects were significantly higher than in healthy controls. In conclusion, infantile SBS results in shorter stature than was expected from their calculated TH. BMC was lower than reference values, but the subjects had normal weight for height and %BF.

Generic, symptom based, exercise rehabilitation; integrating patients with COPD and heart failure

BACKGROUND

Patients with Chronic Heart Failure (CHF) develop similar symptoms of exertional breathlessness and fatigue as patients with COPD. Although pulmonary (exercise based) rehabilitation (PR) is an integral part of the management of COPD, the potential for exercise rehabilitation (ER) to assist patients with CHF may not be as readily appreciated. We investigated whether combined ER for patients with CHF and COPD was feasible and effective using the model of PR.

METHODS

57 patients with CHF were randomized 2:1 to 7 weeks ER (CHF-ER) or 7 weeks of usual care (CHF-UC). As a comparator 55 patients with COPD were simultaneously recruited to the same ER program (COPD-ER). The primary outcome measure was the Incremental Shuttle Walk Test (ISWT) and the secondary outcome measures were the Endurance Shuttle Walk Test (ESWT), isometric quadriceps strength and health status.

RESULTS

27 CHF and 44 COPD patients completed ER and 17 patients with CHF completed UC. The CHF-ER group made significant improvements, compared to CHF-UC, in the mean (95%CI) ISWT distance; 62(35-89)m vs -6(-11 to 33)m p < 0.001. The CHF-ER group also made statistically significant improvements in health status. The improvements in exercise performance and health status were similar between patients with CHF and COPD, treated with ER.

CONCLUSION

Patients with CHF who undergo ER improve similarly in their exercise performance and health status to COPD. Combined training programs for COPD and CHF are effective and feasible, such that service provision could be targeted around common disability rather than the primary organ disease.

Relation of left ventricular ejection fraction and functional capacity with metabolism and inflammation in chronic heart failure with reduced ejection fraction (from the MIMICA Study)

Catabolism and inflammation play a role in the physiopathology of heart failure with reduced ejection fraction and are more pronounced in the advanced stages of the disease. Our aim was to demonstrate that in patients with stable heart failure with reduced ejection fraction adequately treated, a direct relation exists between functional impairment, as evaluated by left ventricular ejection fraction (LVEF) and the 6-minute walking distance (6MWD), and catabolic and inflammatory markers. In 151 outpatients with heart failure and a LVEF of < or =40% (median age 64 years, LVEF 29%, and 6MWD 290 m) we measured the laboratory and body composition parameters that indicate directly or indirectly inflammatory activation, anabolic-catabolic balance, and nutritional status. We performed an analysis stratified by quartiles of LVEF and 6MWD and linear regression analysis to explore our hypothesis. In the linear regression analysis, after adjusting for age, gender, and etiology, LVEF was not related to the metabolic, inflammatory, or nutritional parameters. The 6MWD was directly related to albumin (p = 0.002) and log transformation of dehydroepiandrosterone (p = 0.013) and inversely to adiponectin (p = 0.001) and the log-transformation of high-sensitivity C-reactive protein (p = 0.037). In conclusion, in a population with stable heart failure with reduced ejection fraction, the 6MWD was related to the degree of inflammatory activity and catabolism, but LVEF was not. Even a slightly diminished functional capacity implies underlying inflammation and catabolic activation.

Effects of neuromuscular electrical stimulation of muscles of ambulation in patients with chronic heart failure or COPD: a systematic review of the English-language literature

INTRODUCTION

Despite optimal drug treatment, many patients with congestive heart failure (CHF) or COPD still experience disabling dyspnea, fatigue, and exercise intolerance. They also exhibit significant changes in body composition. Attempts to rehabilitate these patients are often futile because conventional exercise-training modalities are limited by the severity of exertional dyspnea. Therefore, there is substantial interest in new training modalities that do not evoke dyspnea, such as transcutaneous neuromuscular electrical stimulation (NMES).

MATERIALS AND METHODS

In this article, we systematically review the literature that addresses the effects of NMES applied to the muscles of ambulation. We focused on the effects of NMES on strength, exercise capacity, and disease-specific health status in patients with CHF or COPD. We also address the methodological quality of the reported studies as well as the safety of NMES. Manuscripts published prior to December 2007 were identified by searching the Medline/PubMed, Embase, Cochrane Controlled Trials Register, CINAHL, and Physiotherapy Evidence Database (PEDro) databases.

RESULTS

Fourteen trials were identified (nine trials that examined NMES in CHF patients, and five in COPD patients). PEDro scores for methodological quality of the trials were generally moderate to good. Many of the studies reported significant improvements in muscle strength, exercise capacity, and/or health status.

DISCUSSION

Nonetheless, the limited number of studies, the disparity in patient populations, and the variability in NMES methodology prohibit the use of metaanalysis. Yet, from the viewpoint of a systematic review, NMES looks promising as a means of rehabilitating patients with CHF and COPD. There is at least sufficient evidence to warrant more large prospective, randomized, controlled trials.