Tatjana Schütz

Bioimpedance vector analysis as a measure of muscle function

INTRODUCTION The impedance vector produced by an alternating current in the bioimpedance analysis can be seen as a standardised test of cellular mass and function since reactance is believed to reflect the mass and integrity of cell membranes. This study investigated the association between resistance and reactance normalised for height (R/H and Xc/H), and muscle function as assessed by hand grip strength. METHODS 363 patients (172 male, 191 female) from Berlin and Copenhagen were included in the analysis. Whole body impedance was determined by BIA 2000M (Berlin) or EFG2.0 (Copenhagen). Hand grip strength was measured with Digimax electronic hand dynamometer (Berlin) or Jamar dynamometer (Copenhagen). The general linear model was used to assess the association between R/H, Xc/H and hand grip strength. RESULTS We observed a significant association between the impedance parameters R/H and Xc/H and hand grip strength after adjusting for confounding variables (hand grip strength= -36.9 - 0.063 x R/H + 0.573 x Xc/H + 40.7 x Height + 0.115 x Weight - 0.09 x Age + 3.41 (gender=male) + 1.87 (Centre Berlin); Weight: P=0.04, all other coefficients: P<0.0005. r(2)=0.708). CONCLUSIONS The impedance parameters R/H and Xc/H are related to hand grip strength and might therefore be used as a cooperation-independent method to reproducibly assess muscle function.

Weight gain in long-term survivors of kidney or liver transplantation—Another paradigm of sarcopenic obesity?

OBJECTIVE Obesity in transplant recipients is a frequent phenomenon but data from body composition analyses in long-term survivors are limited. Body composition and energy metabolism were studied in patients after liver (LTX) and kidney (KTX) transplantation and patients with liver cirrhosis (LCI) or on chronic hemodialysis (HD) and compared to healthy controls. METHODS In 42 patients 50.0 mo (median; range 17.1-100.6) after LTX and 30 patients 93.0 mo (31.2-180.1) after KTX as wells as in LCI (n = 39) or HD (n = 10) patients mid-arm muscle and fat area, body cell mass, and phase angle (bioimpedance analysis), and resting energy expenditure (indirect calorimetry, REE(CALO)) were measured. RESULTS Obesity was more prevalent in LTX (17%) than LCI (3%) and in KTX (27%) than in HD (10%). In LTX and KTX, phase angle was higher than in end-stage disease (LTX 5.6° [4.1-7.2] versus LCI 4.4° [2.9-7.3], P < 0.001; KTX 5.9° [4.4-8.7] versus HD 4.3° [2.9-6.8]) but was lower in all patient groups than in controls (7.1°; 4.6-8.9; P < 0.001). In LCI and HD REE(CALO) was higher than predicted, while in LTX and KTX REE(CALO) was not different from predicted REE. CONCLUSIONS Despite excellent graft function, many long-term LTX or KTX survivors exhibit a phenotype of sarcopenic obesity with increased fat but low muscle mass. This abnormal body composition is observed despite normalization of the hypermetabolism found in chronic disease and cannot be explained by overeating. The role of appropriate nutrition and physiotherapy after transplantation merits further investigation.

Software for automated MRI‐based quantification of abdominal fat and preliminary evaluation in morbidly obese patients

To present software for supervised automatic quantification of visceral and subcutaneous adipose tissue (VAT, SAT) and evaluates its performance in terms of reliability, interobserver variation, and processing time, since fully automatic segmentation of fat‐fraction magnetic resonance imaging (MRI) is fast but susceptible to anatomical variations and artifacts, particularly for advanced stages of obesity.

Sugar Intake, Taste Changes and Dental Health in Crohn’s Disease

Background: An increased intake of sucrose has been reported in patients with Crohn’s disease (CD). Since subclinical zinc deficiency reduces taste perception for sweet, we investigated taste perception, sucrose intake and plasma zinc levels as well as dental status in CD patients. Methods: Carbohydrate intake and plasma zinc levels were assessed in 24 CD patients and 24 age-matched controls (Con). Taste threshold for sucrose, oral hygiene and caries prevalence were evaluated. Results: In CD a higher sucrose intake (CD 107.1 ± 27.7 vs. Con 71.9 ± 13.7 g/day; p < 0.001), a higher taste threshold for sweet (CD 7.31 vs. Con 2.91 g/l; p < 0.001) and lower plasma zinc levels (CD 11.5 ± 1.5 vs. Con 13.5 ± 2.0 µmol/l; p < 0.001) were found. API was poor (CD 85.4 ± 23.6, Con 31.8 ± 24.1, p < 0.001) and correlated with sucrose intake (p < 0.01). Caries prevalence was increased in patients with longer disease (>3 years) (DMFT index: >3 years 15.6 ± 5.7 vs. <3 years 9.5 ± 4.3; p < 0.05). Conclusion: Dental status in CD patients is poor. Both increased sugar consumption and insufficient oral hygiene seem to cause the higher caries prevalence. Obviously, patients with CD belong to a high-risk group, and preventive measures should be taken early in the course of the disease.

Care problems and nursing interventions related to oral intake in German Nursing homes and hospitals: A descriptive mulitcentre study

BACKGROUND Reduced nutritional intake in care-dependent patients is a risk factor for malnutrition. The prevalence of malnutrition has been extensively reported, but there is little empirical data on the prevalence of the underlying causes of reduced oral intake and the extent of nursing interventions that address malnutrition. OBJECTIVES To report the prevalence of problems that potentially led to decreased nutritional intake. To investigate the association between these problems and body mass index (BMI). To investigate the association between increased care dependency and BMI. To document nutrition-related interventions. DESIGN Cross-sectional multicentre study. SETTING A total of 15 hospitals (H) and 76 nursing homes (NH) in Germany were included. PARTICIPANTS A total of 2930 hospital patients and 5521 nursing home residents were included in the study. The mean age was 66.6 ± 16.7 years (in H) and 84.9 ± 9.8 years (in NH); 14.7% (in H) and 50.4% (in NH) were almost or completely care dependent. A BMI ≤ 20kg/m² was found in 8.5% (in H) and 16.7% (in NH). RESULTS Most hospital patients were eating and drinking independently (72.2%), whereas 58.4% of the nursing home residents needed assistance. Major problems in hospitals were polypharmacy (18.6%), loss of appetite (14.6%) and pain (7.8%); in nursing home common problems were functional problems of the upper extremities (17%), loss of appetite (15.5%) and polypharmacy (15.5%). Patients with a high level of care dependency had higher rates of BMI ≤ 20kg/m². In both settings (H and NH), BMI ≤ 20kg/m² was significantly associated with loss of appetite (odds ratio (OR) 2.6, 95%CI 1.9-3.5 and OR 7.0, 95%CI 5.9-8.3), nausea (OR 2.1, 95%CI 1.3-3.3 and OR 2.8, 95%CI 1.9-4.1), chewing problems (OR 2.1, 95%CI 1.2-3.4 and OR 2.5, 95%CI 2.1-3.1) and swallowing problems (OR 2.3, 95%CI 1.4-3.6 and OR 2.3, 95%CI 1.9-2.8). Nutrition-related nursing interventions were employed more frequently in nursing homes than in hospitals. CONCLUSION A high care dependency in general and in terms of eating and drinking should be addressed in daily care to ensure sufficient nutritional intake. Additional problems, such as loss of appetite, should also be addressed with suitable interventions to prevent malnutrition. Nutrition-related interventions need to be increased in German health care facilities.

Predictive accuracy of single‐ and multi‐slice MRI for the estimation of total visceral adipose tissue in overweight to severely obese patients

The quantification of visceral adipose tissue (VAT) is increasingly being considered for risk assessment and treatment monitoring in obese patients, but is generally time‐consuming. The goals of this work were to semi‐automatically segment and quantify VAT areas of MRI slices at previously proposed anatomical landmarks and to evaluate their predictive power for whole‐abdominal VAT volumes on a relatively large number of patients. One‐hundred and ninety‐seven overweight to severely obese patients (65 males; body mass index, 33.3 ± 3.5 kg/m2; 132 females; body mass index, 34.3 ± 3.2 kg/m2) underwent MRI examination. Total VAT volumes (VVAT‐T) of the abdominopelvic cavity were quantified by retrospective analysis of two‐point Dixon MRI data (active‐contour segmentation, visual correction and histogram analysis). VVAT‐T was then compared with VAT areas determined on one or five slices defined at seven anatomical landmarks (lumbar intervertebral spaces, umbilicus and femoral heads) and corresponding conversion factors were determined. Statistical measures were the coefficients of variation and standard deviations σ1 and σ5 of the difference between predicted and measured VAT volumes (Bland–Altman analysis). VVAT‐T was 6.0 ± 2.0 L (2.5–11.2 L) for males and 3.2 ± 1.4 L (0.9–7.7 L) for females. The analysis of five slices yielded a better agreement than the analysis of single slices, required only a little extra time (4 min versus 2 min) and was substantially faster than whole‐abdominal assessment (24 min). Best agreements were found at intervertebral spaces L3–L4 for females (σ5/1 = 523/608 mL) and L2–L3 for males (σ5/1 = 613/706 mL). Five‐slice VAT volume estimates at the level of lumbar disc L3–L4 for females and L2–L3 for males can be obtained within 4 min and were a reliable predictor for abdominopelvic VAT volume in overweight to severely adipose patients. One‐slice estimates took only 2 min and were slightly less accurate. These findings may contribute to the implementation of analytical methods for fast and reliable (routine) estimation of VAT volumes in obese patients. Copyright

Outcome models in clinical studies: Implications for designing and evaluating trials in clinical nutrition

BACKGROUND & AIMS The selection of appropriate outcome variables in clinical nutrition is particularly challenging, since nutrition is an adjunct therapy in most cases. Therefore, its effect may be confounded with the primary therapy, and classic biomedical outcomes may not reflect the effect of the nutritional intervention. This paper scrutinizes different alternatives to the biomedical perspective. RESULTS Five different outcome models are proposed and analyzed for their suitability in clinical nutrition studies: biomedical, patient-centered/-reported, health economic, decision-making, and integration of classical and patient-reported endpoints. Most published studies in the field of clinical nutrition make use of biomedical endpoints, but the growing importance of patient-centered/-reported and health economic outcomes is recognized. We recommend avoiding to focus solely on biomedical endpoints in clinical nutrition studies. The availability and value of a broader set of outcome-models should be acknowledged. CONCLUSION Patient-centered/-reported, health economic or combined endpoints are particularly useful to assess the effect of nutritional therapies, especially when applied in conjunction with a primary therapy. The proposed outcome models can also contribute to refine clinical nutrition guidelines in assessing the clinical relevance of the study results.

Evaluation of Transient Elastography, Acoustic Radiation Force Impulse Imaging (ARFI), and Enhanced Liver Function (ELF) Score for Detection of Fibrosis in Morbidly Obese Patients.

Background Liver fibrosis induced by non-alcoholic fatty liver disease causes peri-interventional complications in morbidly obese patients. We determined the performance of transient elastography (TE), acoustic radiation force impulse (ARFI) imaging, and enhanced liver fibrosis (ELF) score for fibrosis detection in bariatric patients. Patients and Methods 41 patients (median BMI 47 kg/m2) underwent 14-day low-energy diets to improve conditions prior to bariatric surgery (day 0). TE (M and XL probe), ARFI, and ELF score were performed on days -15 and -1 and compared with intraoperative liver biopsies (NAS staging). Results Valid TE and ARFI results at day -15 and -1 were obtained in 49%/88% and 51%/90% of cases, respectively. High skin-to-liver-capsule distances correlated with invalid TE measurements. Fibrosis of liver biopsies was staged as F1 and F3 in n = 40 and n = 1 individuals. However, variations (median/range at d-15/-1) of TE (4.6/2.6–75 and 6.7/2.9–21.3 kPa) and ARFI (2.1/0.7–3.7 and 2.0/0.7–3.8 m/s) were high and associated with overestimation of fibrosis. The ELF score correctly classified 87.5% of patients. Conclusion In bariatric patients, performance of TE and ARFI was poor and did not improve after weight loss. The ELF score correctly classified the majority of cases and should be further evaluated.

Comparison of T1 relaxation times in adipose tissue of severely obese patients and healthy lean subjects measured by 1.5 T MRI

Subcutaneous (SAT) and visceral adipose tissue (VAT) differ in composition, endocrine function and localization in the body. VAT is considered to play a role in the pathogenesis of insulin resistance, type 2 diabetes, fatty liver disease, and other obesity‐related disorders. It has been shown that the amount, distribution, and (cellular) composition of adipose tissue (AT) correlate well with metabolic conditions. In this study, T1 relaxation times of AT were measured in severely obese subjects and compared with those of healthy lean controls. Here, we tested the hypothesis that T1 relaxation times of AT differ between lean and obese individuals, but also between VAT and SAT as well as superficial (sSAT) and deep SAT (dSAT) in the same individual.

Branched-chain amino acids in liver disease: new aspects of long known phenomena.

Purpose of reviewTo provide an overview of findings on the role of branched-chain amino acids (BCAAs) in the pathophysiology, pathobiochemistry, and treatment of liver cirrhosis and its complications that have been published since or were not included in the last review on this topic in 2007 in this journal. Recent findingsThere has been continued interest in the potential of oral BCAA supplements in improving energy metabolism, nitrogen metabolism, carbohydrate metabolism, insulin resistance, severity of liver disease, serum albumin levels, quality of serum albumin, or postoperative complication rates. Unfortunately, many trials suffer from lacking or inadequate controls or small sample size. In a fine example of scientific perseverance, Dutch researchers uncovered the long-known phenomenon of ingested blood being highly comagenic in patients with cirrhosis to be due to the low biologic value of blood protein. The absence of isoleucine and the abundance of leucine in the hemoglobin molecule by way of BCAA antagonism leads to impaired protein synthesis and azotemia paving the way for hepatic encephalopathy. SummaryRecognizing hypoisoleucinemia and BCAA antagonism following gastrointestinal bleeding, and its successful treatment by isoleucine infusion has advanced our understanding of the role of BCAA in liver cirrhosis.