Mirko Otto

Sleeve Gastrectomy and Roux-en-Y Gastric Bypass Lead to Comparable Changes in Body Composition after Adjustment for Initial Body Mass Index

BackgroundBariatric surgery is a safe and established treatment option of morbid obesity. Mere percentage of excess weight loss (%EWL) should not be the only goal of treatment.MethodsOne hundred seventy-three obese patients were included in the study. They underwent either Roux-en-Y gastric bypass (RYGB; nu2009=u2009127, mean body mass index (BMI) 45.7u2009±u20095.7xa0kg/m2) or sleeve gastrectomy (SG; nu2009=u200946, mean BMI 55.9u2009±u20097.8xa0kg/m2) for weight reduction. Body weight and body composition were assessed periodically by bioelectrical impedance analysis.ResultsAfter 1xa0year of observation, %EWL was 62.9u2009±u200918.0xa0% in RYGB and 52.3u2009±u200915.0xa0% in SG (pu2009=u20090.0024). Body fat was reduced in both procedures with a slight preference for SG, and lean body mass was better preserved in the RYGB group. Due to significant differences in the initial BMI between the two groups, an analysis of covariance was performed, which demonstrated no significant differences in the %EWL as well as in the other parameters of body composition 1xa0year after surgery. Using percentage of total weight loss to evaluate the outcomes between the two procedures, no significant difference was found (31.7u2009±u20098.4xa0% in RYGB and 30.5u2009±u20097.6xa0% in SG patients, pu2009>u20090.4).ConclusionsExcess weight loss is highly influenced by the initial BMI. Total weight loss seems to be a better measurement tool abolishing initial weight differences. SG and RYGB do not differ in terms of body composition and weight loss 1xa0year after surgery.

Handgrip Strength as a Predictor for Post Bariatric Body Composition

BackgroundAfter bariatric surgery, the postoperative quality of weight loss is variable. The aim of weight loss treatment is to reduce fat mass while keeping fat free mass, in particular body cell mass (BCM), constant. Detection of low BCM is an important aspect of surgical follow up. Handgrip dynamometry is a rapid and inexpensive test to measure static muscle strength, which is an independent outcome indicator of various medical conditions. The objective of this study is to examine the change in handgrip strength after bariatric surgery and its predictive value for postoperative body composition. Furthermore, this study was carried out at the University Hospital, Germany.MethodsTwenty-five patients who underwent a bariatric procedure (laparoskopic Roux-Y gastric bypass nu2009=u200916 or sleeve resection nu2009=u20099) were included in this study. Bioelectrical impedance analysis and hand-grip strength were measured preoperatively and repeated every 6xa0weeks for 4xa0months. An analysis of variance was performed to observe the changes in these individual parameters.ResultsPostoperatively, all patients showed a significant decrease in the body mass index and body fat. The extracellular mass, BCM, and the lean mass of the patients remained constant. Handgrip strength showed no significant changes during the postoperative course. Nevertheless, the preoperative hand-grip strength showed a strong positive correlation with the postoperative body composition.ConclusionsThis study showed no changes in the static muscle force after bariatric surgery. The preoperative handgrip strength was strongly correlated with postoperative body composition and may be used to identify patients who need more attention before surgery and in the early postoperative phase.

Postoperative changes in body composition--comparison of bioelectrical impedance analysis and magnetic resonance imaging in bariatric patients.

BackgroundRoux-en-Y gastric bypass (RYGB) result in a marked reduction of body fat and also visceral fat (VF) decrease up to 36 % in 16 weeks. This leads to positive effects on cardiometabolic risks, which are known to be correlated with the occurrence of VF. This study analyzed the validity of bioelectrical impedance analysis (BIA) for determining VF in the postoperative course. In addition, magnetic resonance imaging (MRI) was performed for prediction of whole VF in bariatric patients on the basis of a single slice.MethodsEighteen patients, who underwent RYGB (18), were included in this study. MRI and BIA measurements were performed 1 day before surgery, as well as 6, 12, and 24 weeks after surgery.ResultsDuring the postoperative observation period, we found a significant decrease of both subcutaneous fat (SF) and VF. SF measured by MRI was highly correlated with the level of body fat shown by BIA. In contrast, the VF volume, as determined by MRI, showed no correlation with the body fat measured by BIA. In addition, we were able to show a significant correlation between MRI measured VF volume and the particular single-layer fat area.ConclusionsCompared to the widely used bioelectrical impedance analysis to measure changes in body composition after bariatric procedures, a single-layer MRI was superior in determining VF. Single-layer MRI may be a better tool to recognize changes of VF after bariatric procedures.

The Phase Angle of the Bioelectrical Impedance Analysis as Predictor of Post-Bariatric Weight Loss Outcome

BackgroundBariatric surgery is proven to be the most effective therapy for obesity. However, the targeted weight reduction is not always achieved. Reliable predictors for postoperative success are rare. Also, most available predictors, such as gender and socioeconomic status, cannot be influenced. The aim of the study was to assess the reliability of the phase angle (PhA) as a predictor of weight reduction and body composition after bariatric surgery.MethodsOne hundred seventy-three patients (127 with Roux-en-Y gastric bypass and 46 with sleeve gastrectomy), treated between January 2004 and December 2012, were included into this prospective trial. Bioelectrical impedance analysis (BIA) was performed before and five times within the first year after the operation. Correlation between excess weight loss (EWL) was calculated using Pearson’s correlation coefficient and a receiver operating characteristic (ROC) curve.ResultsThe average weight loss was significant with a total weight loss of 30.1xa0%, while the PhA did not show any significant decrease during the first 12xa0months after surgery. The correlation between the preoperative PhA and the postoperative EWL was significant after 6xa0weeks and after 6, 9, and 12xa0months. The ROC curve has an area of 0.7. The best point of the curve is a PhA of 3.9° with a sensitivity of 81xa0% and a specificity of 54xa0%.ConclusionsPhA may be a useful predictor of EWL after bariatric surgery, and a PhA of 3.9° was calculated as the most suitable cut-off for a successful operation.

Effects of Bariatric Surgery on Non-alcoholic Fatty Liver Disease: Magnetic Resonance Imaging Is an Effective, Non-invasive Method to Evaluate Changes in the Liver Fat Fraction

IntroductionNon-alcoholic fatty liver disease (NAFLD) is considered the most common liver disease worldwide and is highly associated with obesity. The prevalences of both conditions have markedly increased in the Western civilization. Bariatric surgery is the most effective treatment for morbid obesity and its comorbidities such as NAFLD.ObjectivesMeasure postoperative liver fat fraction (LFF) in bariatric patients by using in-opposed-phase MRI, a widely available clinical tool validated for the quantification of liver fatMethodsRetrospective analyses of participants, who underwent laparoscopic Roux-Y-gastric-bypass (17) or laparoscopic sleeve gastrectomy (2) were performed using magnetic resonance imaging (MRI), bioelectrical impedance analysis (BIA), and anthropometric measurements 1xa0day before surgery, as well as 6, 12, and 24xa0weeks after surgery, LFF was calculated from fat-only and water-only MR images.ResultsSix months after surgery, a significant decrease of LFF and liver volume has been observed along with weight loss, decreased waist circumference, and parameters obtained by body fat measured by BIA. LFF significantly correlated with liver volume in the postoperative course.ConclusionsMRI including in-opposed-phase imaging of the liver can detect the quantitative decrease of fatty infiltration within the liver after bariatric surgery and thus could be a valuable tool to monitor NAFLD/NASH postoperatively.

Effect of different liver resection methods on liver damage and regeneration factors VEGF and FGF-2 in mice

BACKGROUNDnDifferent approaches to study liver regeneration in murine models have been proposed. We investigated the effect of different liver resection models on liver damage and regeneration parameters in mice.nnnMETHODSnWe compared the technical aspect of the 2 most commonly used techniques of 50% and 70% liver resection. Liver damage, as determined by the change in serum alanine aminotransferase and aspartate aminotransferase, as well as the regeneration parameters VEGF and FGF-2 were analyzed at 6 time points. A postoperative vitality score was introduced.nnnRESULTSnCholestasis was not observed for either technique. Both resection techniques resulted in full weight recovery of the liver after 240 hours, with no significant difference between sham and resection groups. Postoperative animal morbidity and total protein levels did not differ significantly for either method, indicating early and full functional recovery. However, comparing the mitogenic growth factors FGF-2 and VEGF, a significant increase in serum levels and, therefore, increased growth stimulus, was shown in the extended resection group.nnnCONCLUSIONnExtended resection led to a greater response in growth factor expression. This finding is important since it shows that growth factor response differs acdording to the extent of resection. We have demonstrated the need to standardize murine hepatic resection models to adequately compare the resulting liver damage.

Letter to the Editor for the Manuscript the Complex Interplay of Physical Fitness, Protein Intake and Vitamin D Supplementation After Bariatric Surgery

Dear editor, We agree with the authors that postoperative body composition and maintenance of muscle mass has an influence on the results of bariatric surgery. Preoperative handgrip strength and phase angle (which is part of the bioelectrical impedance analysis, reflecting quality of the lean body mass) are strongly correlated with postoperative body composition changes and even weight loss— this means that physical functionality plays an important role [1, 2]. As the authors mentioned, there are multiple factors responsible for skeletal muscle atrophy and loss of bone mass. However, if the application of proteins and vitamin D will change something on the long-term course is completely unclear. Metcalf et al. showed that a postoperative exercise program can positively influence body composition, that means there are possibilities of influencing [3]. Long-term data does not exist. We agree that the overall supplementation in bariatric patients is not sufficient. Therefore, a structured postoperative follow-up, including frequent clinical examination and investigation of the vitamin serum levels is very important. Several published studies confirmed, that many patients are not adherent to a follow-up program [4]. As described, a structured follow-up program after bariatric surgery is crucial to improve and sustain weight loss [5]. Whether the body composition is influenced positively by such a program is unclear.

Performance of the 1 mg dexamethasone suppression test in patients with severe obesity

To analyze the performance of the 1 mg dexamethasone suppression test (DST) in patients with obesity. Special attention was paid to the influence of interfering medication on DST.

Adipositaschirurgie im Kontext der Schlafmedizin

ZusammenfassungDie morbide Adipositas und ihre Begleiterkrankungen entwickeln sich zu einem stetig wachsenden Gesundheits- und Wirtschaftsproblem. Neben Diabetes gehören auch schlafbezogene Atmungsstörungen zu den „Big Playern“ der adipositasassoziierten Begleiterkrankungen. Aktuell vermag es keine konservative Therapie, die morbide Adipositas und deren Begleiterkrankungen nachhaltig zu verbessern. Die am häufigsten durchgeführten Operationen in Deutschland sind der Roux-Y-Magenbypass (RYGB) und der Schlauchmagen (Gastric Sleeve, GS). Hierzu existiert gute Evidenz, gewonnen aus hoher Datenqualität. Das Risikoprofil der Eingriffe ist überschaubar und gemessen an den (Langzeit‑)Komplikationen der Begleiterkrankungen absolut im Hintergrund. Bariatrische Chirurgie ist, vielfach evident belegt, effektiv und beeinflusst nachhaltig die morbide Adipositas und deren Komorbiditäten.AbstractMorbid obesity and its concomitant diseases are becoming axa0growing health and economic problem. It is known that severe obesity is related to diseases like diabetes, arterial hypertension, dyslipoproteinemia, sleep apnea, and numerous other serious illnesses including cancer. Currently, there is no conservative therapy to sustainably improve morbid obesity and its comorbidities. The most commonly performed surgeries in Germany are the Roux-Y gastric bypass (RYGB) and the sleeve gastrectomy for which there is good evidence gained from high quality data. Bariatric procedures can be performed with operative mortality no greater than cholecystectomy and has evolved as an effective and safe therapeutic option for treating morbid obesity. It can achieve sustained weight loss, remission of comorbidities and leads to an improved quality of life.

Retinopathy in an obesity WHO III cohort: prevalence and risk factors

Objective To assess retinopathy and its risk factors in an obesity WHO III cohort. Methods In the Mannheim Obesity Study, 277 subjects with obesity WHO III aged 18–64u2005years were examined in a cross-sectional approach. Screening for retinopathy was performed using 3-field retinal photography. Endothelial function was assessed using arteriole-to-venule ratio and flicker light analysis. Subjects with and without retinopathy were analysed for anthropometry, metabolic, vascular and renal parameters. Results Retinopathy was found in 18 of the 277 subjects (6.5%). Prevalence of retinopathy was 16.7% in subjects with and 3.4% in subjects without diabetes mellitus. Between subjects with and without retinopathy there were significant differences in diabetes prevalence (61.1% vs 21.7%, p<0.001), systolic blood pressure (145.56 vs 131.73u2005mmu2005Hg, p=0.005), intima-media thickness (0.7 vs 0.59u2005mm, p=0.034), dilatation of retinal veins in response to flicker light (2.24% vs 4.28%, p=0.004) and creatinine (0.92 vs 0.83u2005mg/dL, p=0.011). Stepwise logistic regression analysis revealed that the presence of diabetes mellitus led to an 8.3-fold increased risk for retinopathy (OR 8.3, p=0.049, 95% CI 1.01 to 67.49), whereas risk for retinopathy decreased by nearly 50% (OR 0.54, p=0.032, 95% CI 0.30 to 0.95) with each percentage increase in venous dilatation in response to flicker light. Conclusions Retinopathy prevalence in our obesity WHO III cohort is low. Presence of diabetes mellitus is the most important risk factor for retinopathy. Preserved venular function indicates protection from retinopathy. Trial registration number NCT00770276, Results.