Preoperative risk factors for early postoperative bleeding after Roux-en-Y gastric bypass surgery: a systematic review and meta-analysis

PURPOSE

Although bariatric surgery is an effective intervention for obesity, it comes with risks such as early postoperative bleeding (EPB). Identifying preoperative risk factors for this complication can help patients' risk stratification and optimization. We performed a systematic review and meta-analysis to find predictors for early postoperative bleeding after Roux-en-Y gastric bypass (RYGB).

METHODS

We conducted a systematic review, searching PubMed, Cochrane Library, and Web of Science until November 2023. We performed a random-effects meta-analysis to explore preoperative risk factors associated with early postoperative bleeding after RYGB. Sources of heterogeneity were explored by leave-one-out analyses.

RESULTS

23 studies were included, comprising 232,488 patients. Male gender (meta-analytical RR = 1.42, 95%CI = 1.21-1.66, I2 = 18%, Q Cochran test p-value = 0.29) and revisional surgery (meta-analytical RR = 1.35, 95%CI = 1.12-1.62, I2 = 22%, Q Cochran test p = 0.21) were associated with higher risk of EPB. On average, patients with EPB were older than the remainder (MD for the mean age = 2.82 years, 95%CI = 0.97-4.67, I2 = 0.00%, Q Cochran test p = 0.46). Except for hypertension (meta-analytical RR = 1.33, 95%CI = 1.02-1.73, I2 = 66%, Q Cochran test p < 0.0001), comorbidities were not associated with a higher risk of EPB.

CONCLUSION

Preoperative risk factors, including age, gender, hypertension, and revisional bariatric surgery, are associated with early postoperative bleeding after RYGB. Further primary studies, with higher methodological quality, are required to detail more risk factors.

Impact of a Multicomponent Exercise Training Program on Muscle Strength After Bariatric Surgery: A Randomized Controlled Trial

PURPOSE

This study examined the benefits of an 11-months multicomponent exercise program (MEP) on muscular strength (MS) after bariatric surgery.

METHODS

Of the 84 randomized patients, 41 participants from the exercise group (EG) and 20 participants from the control group (CG) were included in the analysis. The EG received supervised MEP for 11 months, starting 1-month post-bariatric surgery (BS) in addition to standard medical care, while the CG received medical care recommendations only. Knee and trunk MS was assessed by isokinetic dynamometry pre-surgery, 1-, 6-, and 12-month post-surgery, while body composition was assessed by dual-energy X-ray absorptiometry.

RESULTS

The MEP did not significantly impact absolute MS in the dominant knee and trunk regions at 6- and 12-month post-BS. However, relative MS showed significant improvements. At 6-month post-BS, knee flexion at 60°/s relative to body weight (BW) increased significantly (p = 0.047), as did knee extension at 180°/s relative to BW (p = 0.009), and knee extension at 60°/s relative to total lean mass (p=0.040). At 12-month post-BS, knee flexion at 60°/s relative to BW also significantly improved (p=0.038).

CONCLUSION

While absolute MS was not significantly improved with MEP, this study found significant enhancements in relative MS, particularly in dominant knee flexion post-MEP participation. Further research should explore different exercise intensities and frequencies to optimize postoperative MS recovery post-BS.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (NCT02843048).

Roux-en-Y gastric bypass and sleeve gastrectomy as revisional bariatric procedures after adjustable gastric banding: a retrospective cohort study

INTRODUCTION

The frequency of revisional bariatric surgery is increasing, but its effectiveness and safety are not yet fully established. The aim of our study was to compare short-term outcomes of primary (pRYGB and pSG) and revisional bariatric surgeries (rRYGB and rSG).

METHODS

We performed a retrospective cohort study assessing all patients submitted to primary and revisional (after a failed AGB) RYGB and SG in 2019. Each patient was followed-up at 6 months and 12 months after surgery. We compared pRYGB vs. rRYGB, pSG vs. rSG and rRYGB vs. rSG on weight loss, surgical complications, and resolution of comorbidities.

RESULTS

We assessed 494 patients, of which 18.8% had undergone a revisional procedure. Higher weight loss at 6 and 12 months was observed in patients undergoing primary vs. revisional procedures. Patients submitted to rRYGB lost more weight than those with rSG (%EWL 12 months = 82.6% vs. 69.0%, p < 0.001). Regarding the resolution of obesity-related comorbidities, diabetes resolution was more frequent in pRYGB than rRYGB (54.2% vs. 25.0%; p = 0.038). Also, 41.7% of the patients who underwent rRYGB had dyslipidemia resolution vs. 0% from the rSG group (p = 0.035). Dyslipidemia resolution was also more common in pSG vs. rSG (68.6% vs. 0.0%; p = 0.001). No significant differences in surgical complications were found.

CONCLUSION

Revisional bariatric surgery is effective and safe treating obesity and related comorbidities after AGB. Primary procedures appear to be associated with better weight loss outcomes. Further prospective studies are needed to better understand the role of revisional bariatric surgery.

Effects of a supervised exercise training on body composition after bariatric surgery: a randomized controlled trial

OBJECTIVE

This study aimed to determine the effects of a multicomponent exercise intervention during the first year post-bariatric surgery (BS) on body composition, weight loss (WL), energy expenditure, and nutrient intake.

METHODS

A total of 84 patients were included in this study and were randomly assigned to either an exercise group (n = 41) or a control group (n = 20). The exercise group participated in a multicomponent exercise program that began 1-month post-BS, whereas the control group received only standard medical care post-BS. Body composition was assessed by dual-energy x-ray absorptiometry, and physical activity energy expenditure was assessed by accelerometers. Nutritional intake was assessed through a 4-day food diary.

RESULTS

A total of 6-months post-BS, exercise was found to be effective in mitigating the loss of lower-limb and appendicular lean mass (LM), as well as favoring trunk fat mass (FM) loss. Moreover, it further decreased percent FM and promoted additional excess WL. After 12 months, exercise not only reduced waist circumference but also helped to lessen the loss of total, trunk, and appendicular LM.

CONCLUSIONS

Exercise further induced trunk fat mass, percent FM, excess WL, and waist circumference reductions. Moreover, exercise attenuated the loss of total and regional LM.

Incidence of symptomatic gallstones after bariatric surgery: the impact of expectant management

BACKGROUND

Bariatric surgery is the most effective treatment for sustained weight reduction and obesity-related comorbidities. The development of gallstones as a result of rapid weight loss is a well-known consequence of bariatric procedures. It remains unclear, if there is an increased risk of these gallstones becoming symptomatic.

METHODS

A retrospective analysis of 505 consecutive patients submitted to either Roux-en-Y Gastric Bypass or Sleeve Gastrectomy between January and December 2019 was performed. The aim of our study was to determine the incidence of symptomatic cholelithiasis in asymptomatic patients with their gallbladder in situ after bariatric surgery and to identify potential risk factors for its development.

RESULTS

Of the 505 patients included, 79 (15.6%) underwent either previous cholecystectomy. (n = 67, 84.8%) or concomitant cholecystectomy during bariatric surgery (n = 12, 15.2%). Among the remaining 426 (84.4%) patients, only 8 (1.9%) became symptomatic during the 12-month follow-up period. When compared with patients who remained asymptomatic, they had a higher median preoperative BMI (47.0 vs. 42.8, p = 0.046) and prevalence of cholelithiasis on preoperative ultrasound (62.5% vs. 10.7%, p = 0.001). Multivariate analysis revealed preoperative BMI and cholelithiasis on preoperative ultrasound as independent risk factors for symptomatic biliary disease (OR 1.187, 95%CI 1.025-1.376, p = 0.022 and OR 10.720, 95%CI 1.613-71.246, p = 0.014, respectively).

CONCLUSION

Considering a low incidence of symptomatic gallstones after bariatric surgery, concomitant cholecystectomy should only be performed in symptomatic patients undergoing bariatric surgery. Preoperative factors, such as a higher BMI and positive ultrasound for cholelithiasis, may be related to the development of symptomatic gallstones.

Using Raw Accelerometer Data to Predict High-Impact Mechanical Loading

The purpose of this study was to develop peak ground reaction force (pGRF) and peak loading rate (pLR) prediction equations for high-impact activities in adult subjects with a broad range of body masses, from normal weight to severe obesity. A total of 78 participants (27 males; 82.4 ± 20.6 kg) completed a series of trials involving jumps of different types and heights on force plates while wearing accelerometers at the ankle, lower back, and hip. Regression equations were developed to predict pGRF and pLR from accelerometry data. Leave-one-out cross-validation was used to calculate prediction accuracy and Bland-Altman plots. Body mass was a predictor in all models, along with peak acceleration in the pGRF models and peak acceleration rate in the pLR models. The equations to predict pGRF had a coefficient of determination (R²) of at least 0.83, and a mean absolute percentage error (MAPE) below 14.5%, while the R² for the pLR prediction equations was at least 0.87 and the highest MAPE was 24.7%. Jumping pGRF can be accurately predicted through accelerometry data, enabling the continuous assessment of mechanical loading in clinical settings. The pLR prediction equations yielded a lower accuracy when compared to the pGRF equations.

Risk and Prophylactic Management of Gallstone Disease in Bariatric Surgery: a Systematic Review and A Bayesian meta-analysis

BACKGROUND

The frequency and management of gallstone disease (GD) in bariatric patients, including the role of routine prophylactic concomitant cholecystectomy (CCY), are still a matter of debate. This study aims to assess the risk of de novo GD in patients undergoing bariatric surgery (BS) and their predictive factors, as well as mortality and morbidity in prophylactic CCY compared to BS alone.

METHODS

We performed a systematic review, searching PubMed, EMBASE, and Web of Science until April 2021. We performed a Bayesian meta-analysis to estimate the risk of GD development after BS and the morbidity and mortality associated with BS alone versus BS + prophylactic CCY. Sources of heterogeneity were explored by meta-regression analysis.

RESULTS

The risk of de novo post bariatric GD was 20.7% (95% credible interval [95% CrI] = 13.0-29.7%; I² = 75.4%), and that of symptomatic GD was 8.2% ([95% CrI] = 5.9-11.1%; I² = 66.9%). Pre-operative average BMI (OR = 1.04; 95% CrI = 0.92-1.17) and female patients' proportion (OR = 1.00; 95% CrI = 0.98-1.04) were not associated with increased risk of symptomatic GD. BS + prophylactic CCY was associated with a 97% probability of a higher number of postoperative major complications compared to BS alone (OR = 1.74, 95% CrI = 0.97-3.55; I² = 56.5%). Mortality was not substantially different between the two approaches (OR = 0.79; 95% CrI = 0.03-3.02; I² = 20.7%).

CONCLUSION

The risk of de novo symptomatic GD after BS is not substantially high. Although mortality is similar between groups, odds of major postoperative complications were higher in patients submitted to BS + prophylactic CCY. It is still arguable if prophylactic CCY is a fitting approach for patients with a preoperative lithiasic gallbladder.

Mechanical loading prediction through accelerometry data during walking and running

Currently, there is no way to assess mechanical loading variables such as peak ground reaction forces (pGRF) and peak loading rate (pLR) in clinical settings. The purpose of this study was to develop accelerometry-based equations to predict both pGRF and pLR during walking and running. One hundred and thirty one subjects (79 females; 76.9 ± 19.6kg) walked and ran at different speeds (2-14km·h^-1) on a force plate-instrumented treadmill while wearing accelerometers at their ankle, lower back and hip. Regression equations were developed to predict pGRF and pLR from accelerometry data. Leave-one-out cross-validation was used to calculate prediction accuracy and Bland-Altman plots. Our pGRF prediction equation was compared with a reference equation previously published. Body mass and peak acceleration were included for pGRF prediction and body mass and peak acceleration rate for pLR prediction. All pGRF equation coefficients of determination were above 0.96, and a good agreement between actual and predicted pGRF was observed, with a mean absolute percent error (MAPE) below 7.3%. Accuracy indices from our equations were better than previously developed equations. All pLR prediction equations presented a lower accuracy compared to those developed to predict pGRF. Walking and running pGRF can be predicted with high accuracy by accelerometry-based equations, representing an easy way to determine mechanical loading in free-living conditions. The pLR prediction equations yielded a somewhat lower prediction accuracy compared with the pGRF equations.

Effects of a Multicomponent Exercise Training Program on Balance Following Bariatric Surgery

Patients who undergo bariatric surgery (BS) have an increased risk of falls. Our aim was to determine if a multicomponent exercise intervention after BS improves balance. Eighty-four patients with obesity enrolled for BS were recruited and 1 month after BS randomly allocated to a control (CG; standard medical care) or exercise group (EG; exercise plus standard medical care) consisting of a supervised multicomponent training program (3d/week; 75 min/session; 5 months). Anthropometry, lower limb muscle strength (isokinetic dynamometer), vitamin D (ELISA) and balance in bipedal stance (force platform) were assessed pre-BS, 1 month and 6 months post-BS. One month post-BS, significant balance improvements were observed, namely in antero-posterior center of gravity (CoG) displacement and velocity, and medio-lateral and total CoG velocity. Between 1- and 6-months post-BS, improvements in balance were observed only in the EG, with a significant treatment effect on CoG displacement area and antero-posterior CoG displacement. No significant differences were observed between EG and CG over time in any of the anthropometric, muscle strength, and vitamin D variables assayed. In conclusion, a multicomponent exercise intervention program improves some balance parameters in patients with severe obesity following BS and therefore should be part of post-BS follow-up care as a potential strategy to reduce falls and associated injuries.

Vitamin B Complex Deficiency After Roux-en-Y Gastric Bypass and Sleeve Gastrectomy-a Systematic Review and Meta-Analysis

Bariatric surgery, although an effective method, still has complications, like nutritional deficiencies. Our aim was to summarize the evidence on the frequency of complex B vitamin deficiencies in studies comparing Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). We included 25 studies for qualitative synthesis and 21 studies for quantitative synthesis. Relevant data was extracted, including proportion of patients with deficiency and mean serum vitamin values in 3 different timeframes. B12 and folate were the most prevalent deficiencies. B12 deficiency was more common after RYGB and folate serum mean levels were higher after RYGB. SG causes less nutrient deficiency and is therefore a better technique from this point of view. More studies are needed on B2, B3, and B6 vitamins to draw better conclusions.

Proteomic Identification of a Gastric Tumor ECM Signature Associated With Cancer Progression

The extracellular matrix (ECM) plays an undisputable role in tissue homeostasis and its deregulation leads to altered mechanical and biochemical cues that impact cancer development and progression. Herein, we undertook a novel approach to address the role of gastric ECM in tumorigenesis, which remained largely unexplored. By combining decellularization techniques with a high-throughput quantitative proteomics approach, we have performed an extensive characterization of human gastric mucosa, uncovering its composition and distribution among tumor, normal adjacent and normal distant mucosa. Our results revealed a common ECM signature composed of 142 proteins and indicated that gastric carcinogenesis encompasses ECM remodeling through alterations in the abundance of 24 components, mainly basement membrane proteins. Indeed, we could only identify one de novo tumor-specific protein, the collagen alpha-1(X) chain (COL10A1). Functional analysis of the data demonstrated that gastric ECM remodeling favors tumor progression by activating ECM receptors and cellular processes involved in angiogenesis and cell-extrinsic metabolic regulation. By analyzing mRNA expression in an independent GC cohort available at the TGCA, we validated the expression profile of 12 differentially expressed ECM proteins. Importantly, the expression of COL1A2, LOX and LTBP2 significantly correlated with high tumor stage, with LOX and LTBP2 further impacting patient overall survival. These findings contribute for a better understanding of GC biology and highlight the role of core ECM components in gastric carcinogenesis and their clinical relevance as biomarkers of disease prognosis.

The effect of bariatric surgery on gravitational loading and its impact on bone mass

INTRODUCTION

Mechanical unloading associated with weight loss might be one of the main causes for bariatric surgery (BS) induced bone loss. However, no study has tested this hypothesis through objectively measured accelerometry-derived gravitational loading. We aimed to assess how gravitational loading changes following BS and how this correlates with bone mass losses.

METHODS

Twenty-one patients submitted to gastric bypass were assessed before, 1, 6 and 12 months after BS for areal bone mineral density (BMD), calciotropic hormones, sclerostin, body composition and daily physical activity. Gravitational loading was determined as the sum of ground reaction forces assessed by accelerometer which considered the interaction between weight and daily ambulation.

RESULTS

Mechanical stimuli promoted through the significant increase in steps number counterbalanced the gravitational loading decreases derived from the significant weight loss after BS. Gravitational loading volume decreased between pre-BS and 1 month post-BS (-2215 kN·d^-1; p = .023), but remained stable between 6 and 12 months post-BS, despite decreases on hip (-7.0%; p < .001), femoral neck (-8.8%; p < .001) and lumbar spine (-5.2%; p < .001) BMD. Serum sclerostin increased from pre-BS to 1 month post-BS (+0.118 ng·mL^-1; p = .021), returning to pre-BS levels 6 months after surgery. Neither vitamin D nor parathyroid hormone were affected by BS. Weight variation was a predictor of BMD decreases at total hip (R² = 0.06; p = .026) and femoral neck (R² = 0.12; p = .022), whereas daily gravitational loading volume was not. Fat and lean mass changes were also predictors of BMD decrease at total hip (R² = 0.05; p = .031) and femoral neck (R² = 0.14; p = .010), respectively.

CONCLUSION

Our findings suggest that gravitational loading only decreased during the first month after surgery remaining stable thereafter, and these changes do not seem to explain BS-induced bone loss. The association between weight and bone loss seems to result from other physiological aspects, fat and lean mass loss, rather than from gravitational loading decrease.

Comparative Effectiveness of Bariatric Surgeries in Patients with Type 2 Diabetes Mellitus and BMI ≥ 25 kg/m2: a Systematic Review and Network Meta-Analysis

PURPOSE

In patients with type 2 diabetes mellitus (T2DM), bariatric surgery appears to be more effective than medical treatment (MT) at improving glycaemic control and decreasing cardiovascular risk. However, long-term effectiveness has not been systematically assessed using randomised controlled trials. In this study, we aimed to systematically assess randomised controlled trials, with at least 5 years of follow-up, on bariatric surgery in patients with T2DM and BMI ≥ 25 kg/m², as well as to compare different bariatric procedures.

MATERIAL AND METHODS

PubMed, SCOPUS and Web of Science were searched. We performed a network meta-analysis to evaluate the comparative effectiveness of the different procedures and MT in terms of full T2DM remission, weight loss, complications and cardiometabolic biomarkers. The quality of evidence was assessed using the Cochrane Risk of Bias Tool and CINeMA.

RESULTS

We included 11 primary studies. Laparoscopic one-anastomosis gastric bypass (LOAGB) was found to be one of the most effective treatments for full remission of T2DM (I² = 0, inconsistency p value = 0.9223). Biliopancreatic diversion without duodenal switch was found to be more effective than laparoscopic Roux-en-Y gastric bypass and laparoscopic adjustable gastric banding regarding percent total cholesterol and low-density lipoprotein change. Regarding percent high-density lipoprotein and weight change, all analysed surgical treatments were shown to be more effective than MT. The confidence rating in our results was overall moderate, but most studies had high risk of performance and detection bias.

CONCLUSION

Bariatric surgery seems to be effective for T2DM remission. LOAGB appears to be a good option in this context, and a possible alternative to laparoscopic duodenal switch, but the included primary studies in our review are not sufficiently powered to establish a more definitive conclusion. More studies with longer follow-up times are needed to comprehensively assess bariatric surgery in T2DM.

Obesity and Cancer: the Profile of a Population who Underwent Bariatric Surgery

INTRODUCTION

Obesity is a significant risk factor for cancer incidence and mortality. The number of patients with obesity who undergo bariatric surgery is increasing; however, the impact of such a procedure in affecting the risk of cancer is not completely understood yet.

METHODS

We conducted a retrospective unicentric cohort study to characterize the occurrence of cancer in patients who underwent bariatric surgery from January 2010 to December 2018. For cases of cancer identified after bariatric surgery, we performed a cancer-free survival analysis over time. We also performed a cross-sectional analysis of demographic and clinical characteristics at the time of surgery and compared patients with or without a cancer diagnosis.

RESULTS

Of the 2578 patients who underwent bariatric surgery, 117 patients (4.5%) were diagnosed with a cancer. Fifty-nine cases were diagnosed before surgery, and the remaining 58 cases occurred after the bariatric procedure. The prevalence of cancer was more accentuated in women (4.9%) than among men (2.7%). Thyroid and breast cancer were the most frequent before and after bariatric surgery, respectively. On average, patients with cancer diagnosis were older (49.0 vs 43.3 years, p<0.001) and with a lower level of education (7.4 vs 8.6 school years, p=0.002).

CONCLUSION

Almost all the cases of cancer identified in this study were obesity-related cancers. Further prospective studies are needed to extend the current knowledge regarding the cancer risk profile of patients who undergo bariatric surgery.

How Does Bariatric Surgery Affect Fall Risk Factors?

PURPOSE

This study aimed to assess bariatric surgery (BS) effect on fall risk factors.

MATERIALS AND METHODS

Fifteen patients undergoing BS (intervention group, IG) and 10 non-surgical obese patients (control group, CG) were recruited. IG was assessed at pre-surgery and 6 months after BS, while CG was assessed at baseline and reassessed after 6 months. At both time-points, anthropometry, lower limbs muscle strength (isokinetic dynamometer), balance in bipedal stance (force platform), daily physical activity (accelerometry), and health-related quality of life (SF-36 questionnaire) were assessed.

RESULTS

At baseline, there were no differences between CG and IG for all parameters analyzed. Compared to CG, 6 months post-BS, the IG decreased weight, body mass index, waist and hip circumference. Balance showed limited improvements, with gains observed only on antero-posterior and total center of pressure velocity. Muscle strength displayed a divergent evolution 6 months after BS, with a decrease in absolute strength but an increase in relative strength. Although BS did not induce significant changes in time spent in different physical activity intensities, it decreased time in sedentary behavior and increased number of daily steps. Post-BS patients reported substantial improvements in quality-of-life, especially in physical function.

CONCLUSION

Patients seem to overestimate their actual physical fitness improvements attained after BS, which combined with increases in physical activity, might increase the likelihood of engaging in risky daily tasks to what they are physically not prepared to, consequently increasing fall risk.

The Effect of an Exercise Intervention Program on Bone Health After Bariatric Surgery: A Randomized Controlled Trial

Exercise has been suggested as a therapeutic approach to attenuate bone loss induced by bariatric surgery (BS), but its effectiveness remains unclear. Our aim was to determine if an exercise-training program could induce benefits on bone mass after BS. Eighty-four patients, submitted to gastric bypass or sleeve gastrectomy, were randomized to either exercise (EG) or control group (CG). One month post-BS, EG underwent a 11-month supervised multicomponent exercise program, while CG received only standard medical care. Patients were assessed before BS and at 1, 6, and 12 months post-BS for body composition, areal bone mineral density (BMD), bone turnover markers, calciotropic hormones, sclerostin, bone material strength index, muscle strength, and daily physical activity. A primary analysis was conducted according to intention-to-treat principles and the primary outcome was the between-group difference on lumbar spine BMD at 12 months post-BS. A secondary analysis was also performed to analyze if the exercise effect depended on training attendance. Twelve months post-BS, primary analysis results revealed that EG had a higher BMD at lumbar spine (+0.024 g∙cm^-2 [95% confidence interval (CI) 0.004, 0.044]; p = .015) compared with CG. Among total hip, femoral neck, and 1/3 radius secondary outcomes, only 1/3 radius BMD improved in EG compared with CG (+0.013 g∙cm^-2 [95% CI 0.003, 0.023]; p = .020). No significant exercise effects were observed on bone biochemical markers or bone material strength index. EG also had a higher lean mass (+1.5 kg [95% CI 0.1, 2.9]; p = .037) and higher number of high impacts (+51.4 [95% CI 6.6, 96.1]; p = .026) compared with CG. In addition, secondary analysis results suggest that exercise-induced benefits may be obtained on femoral neck BMD but only on those participants with ≥50% exercise attendance compared with CG (+5.3% [95% CI 2.0, 8.6]; p = .006). Our findings suggest that an exercise program is an effective strategy to ameliorate bone health in post-BS patients. © 2020 American Society for Bone and Mineral Research (ASBMR).

How Far Can Our Expectations Go on Revisional Bariatric Surgery After Failed Adjustable Gastric Banding?

PURPOSE

Bariatric surgery has proven its effectiveness in the treatment of obesity and related comorbidities. However, several procedures may be required to treat this chronic disease and/or complications after bariatric surgery. The most frequent revisional surgeries performed after failed laparoscopic adjustable gastric banding (AGB) have been Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). The aim of this study is to compare medium-term outcomes of primary and revisional bariatric procedures.

MATERIAL AND METHODS

Single institution, matched case-control study of obese patients submitted to bariatric surgery, divided into four groups of 50 patients: (A) primary RYGB; (B) primary SG; (C) revisional Roux-en-Y gastric bypass (rRYGB) after failed laparoscopic AGB; (D) revisional sleeve gastrectomy (rSG) after failed laparoscopic AGB. Demographic variables, surgical procedures characteristics and complications, weight loss outcomes and resolution of comorbidities were compared.

RESULTS

Mortality and morbidity were comparable between primary and revisional procedures. Weight loss outcomes were inferior in patients submitted to rRYGB when compared to those submitted to RYGB, with no significant differences found when comparing the other groups. Regarding comorbidities' outcomes, only patients submitted to rSG had lower odds of comorbidities' improvement. Patients submitted to rRYGB had an odd 7 times higher of comorbidities' improvement than those submitted to rSG, independent of weight loss outcomes.

CONCLUSION

Revisional surgeries are safe procedures with adequate weight loss outcomes in this difficult set of patients. The choice of revisional procedure may not influence weight loss outcomes, but rRYGB seems to be a better option regarding comorbidities' resolution.

Beta Cell Function as a Baseline Predictor of Weight Loss After Bariatric Surgery

BACKGROUND

Obesity is a multifactorial disease, which is strongly associated to other metabolic disorders. Bariatric surgery is the most effective treatment of morbid obesity. The role of beta cell function in weight loss after bariatric surgery is uncertain.

AIM

To evaluate the association between beta cell function and percentage of total body weight loss (TBWL%) 1, 2, 3, and 4 years after bariatric surgery in patients with morbid obesity.

METHODS

Retrospective longitudinal study in patients with morbid obesity followed in our center between January 2010 and July 2018. Patients were excluded if they had diabetes at baseline or missing data on the needed parameters. We evaluated baseline Homeostatic Model Assessment of IR, Homeostatic Model Assessment of β-cell function (HOMA-beta), Quantitative Insulin Sensitivity Check Index, and Matsuda and DeFronzo index, and TBWL% at years 1 to 4. Linear regression models were used to evaluate the association of indexes of insulin resistance with TBWL% (unadjusted and adjusted for age, sex, BMI, and type of surgery).

RESULTS

There were 1,561 patients included in this analysis. HOMA-beta was negatively associated with TBWL% at second, third, and fourth years post-surgery (β = -1.04 [-1.82 to -0.26], p<0.01; β = -1.16 [-2.13 to -0.19], p=0.02; β = -1.29 [-2.64 to 0.06], p=0.061, respectively). This was not observed in the first year post-surgery nor for the other indexes. Glycemia at baseline was positively associated to EWL% at second and third years post-surgery.

CONCLUSION

β-cell function at baseline seems to be associated to long-term weight loss, explicitly after the first year post bariatric surgery. This might be a helpful predictor of weight loss in clinical practice.

Testing amino acid-codon affinity hypothesis using molecular docking

Genetic code refers to a set of rules that assign trinucleotides called codons to amino acids in the process of protein synthesis. Investigating the genetic code's logic and its evolutionary origin has always been both intriguing and challenging. While the correspondence rules between codons and amino acids in the genetic code are well-known, it is still unclear whether those assignments can be explained based on energetic or/and entropic arguments. As an attempt at deciphering basic thermodynamic rules governing DNA translation, we used molecular docking to investigate the ability of amino acids to bind to their corresponding anticodon compared to other codons. The total number of 1280 direct docking interactions have been performed for each amino acid-codon/anti-codon case to find whether the amino acids have a preference to bind to their cognate anticodons or codons. Based on docking scores which are expected to correlate with binding affinity, no correlation with genetic correspondence rules was observed suggesting a more subtle process, other than direct binding, to explain codon-amino-acid specificity.

Bariatric Surgery Induces Retinal Thickening Without Affecting the Retinal Nerve Fiber Layer Independent of Diabetic Status

PURPOSE

Obese patients have neurodegeneration of the optic nerve demonstrated by decreased peripapillary nerve fiber layer. Whether bariatric surgery reverses this neurodegenerative process has not been explored. We aimed to evaluate the impact of bariatric surgery in the structure of the retina and optic nerve.

METHODS

Multicentric observational study. Obese patients scheduled for bariatric surgery were consecutively recruited and included in the study and evaluated before and 6-12 months after the intervention. The retinal structure was evaluated as retinal thickness in the different retinal layers in the foveal, perifoveal, and parafoveal regions using optical coherence tomography. Choroidal thickness and optic nerve retinal nerve fiber layer thickness were also evaluated.

RESULTS

Eighty eyes from 40 participants were included. Globally, we found a significant thickening of the retina after bariatric surgery (foveal: 273.5 (21.5) μm vs 280.0 (28.8) μm, p < 0.001; parafoveal 332.4 ± 17.8 μm vs 336.6 ± 15.9 μm, p = 0.003; perifoveal: 293.4 ± 13.8 μm vs 295.7 ± 14.9 μm; p = 0.001), whereas no significant differences were found for the ganglion cell layer, choroid, or peripapillary nerve fiber layer thickness. The retinal thickening was confined to inner retinal layers and was independent of the diabetic status of the patients. After multivariate adjustment, HbA1c variation, preoperative C-peptide, preoperative hypertension, preoperative OSA, and preoperative LDL and TG levels seem to be clinical predictors of retinal thickening.

CONCLUSIONS

We found a significant thickening of the retina after bariatric surgery that was independent of the diabetic status. The thickening was confined to inner retinal layers and may represent and improve perfusion. The peripapillary nerve fiber layer remained unchanged after the surgery.

Laparoscopic sleeve gastrectomy in morbidly obese adolescents: Initial experience of a Pediatric Multidisciplinary Unit

INTRODUCTION

Childhood obesity is a significant health problem worldwide, associated with significant metabolic and cardiovascular morbidity. Recent evidence points to metabolic and bariatric surgery as a safe and effective treatment for morbidly obese adolescents. We aim to report the initial results after laparoscopic sleeve gastrectomy (LSG) for adolescent patients in a pediatric center.

MATERIAL AND METHODS

Retrospective data review of patients younger than 19 years who underwent LSG for treatment of morbid obesity between 2013 and 2019.

RESULTS

A total of 16 adolescents (12 female, 4 male) with a median age of 17.5 years underwent LSG. Median preoperative weight and body mass index were 129kg and 48.6kg/m^-2, respectively. All patients had at least one comorbidity. Median follow-up was 18.5 months. The overall percent total weight loss was 32.5% and percent excess weight loss was 68%. Resolution of comorbidities was noted in the majority of patients. No perioperative complications were reported.

CONCLUSIONS

Laparoscopic sleeve gastrectomy is a safe and effective option for treatment of morbidly obese adolescents, resulting in significant weight loss and comorbidity resolution with a low risk of complications.

Accelerometer-based prediction of skeletal mechanical loading during walking in normal weight to severely obese subjects

There is no objective way to monitor mechanical loading characteristics during exercise for bone health improvement. We developed accelerometry-based equations to predict ground reaction force (GRF) and loading rate (LR) in normal weight to severely obese subjects. Equations developed had a high and moderate accuracy for GRF and LR prediction, respectively, thereby representing an accessible way to determine mechanical loading characteristics in clinical settings.

INTRODUCTION

There is no way to objectively prescribe and monitor exercise for bone health improvement in obese patients based on mechanical loading characteristics. We aimed to develop accelerometry-based equations to predict peak ground reaction forces (pGRFs) and peak loading rate (pLR) on normal weight to severely obese subjects.

METHODS

Sixty-four subjects (45 females; 84.6 ± 21.7 kg) walked at different speeds (2-6 km·h^-1) on a force plate-equipped treadmill while wearing accelerometers at lower back and hip. Regression equations were developed to predict pGRF and pLR from accelerometry data. Leave-one-out cross-validation was used to calculate prediction accuracy and Bland-Altman plots. Actual and predicted values at different speeds were compared by repeated measures ANOVA.

RESULTS

Body mass and peak acceleration were included for pGRF prediction and body mass and peak acceleration transient rate for pLR prediction. All pGRF equation coefficients of determination were above 0.89, a good agreement between actual and predicted pGRFs, with a mean absolute percent error (MAPE) below 6.7%. No significant differences were observed between actual and predicted pGRFs at each walking speed. Accuracy indices from our equations were better than previously developed equations for normal weight subjects, namely a MAPE approximately 3 times smaller. All pLR prediction equations presented a lower accuracy compared to those developed to predict pGRF.

CONCLUSION

Walking pGRF and pLR in normal weight to severely obese subjects can be predicted with moderate to high accuracy by accelerometry-based equations, representing an easy and accessible way to determine mechanical loading characteristics in clinical settings.

Retinal Nerve Fiber Layer Thickness Decrease in Obesity as a Marker of Neurodegeneration

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a serious condition that is frequently associated with irreversibly vision loss, having a higher incidence among obese women. Our aims were to screen subclinical IIH in obese patients scheduled to bariatric surgery using peripapillary retinal nerve fiber layer (RNFL) thickness and to evaluate if the findings demand the possible need of a preoperative evaluation in this population.

METHODS

This study included 111 eyes from 36 obese patients (86% female, body mass index > 35 kg/m²) scheduled to bariatric surgery and 20 non-obese (body mass index < 25 kg/m²) age-matched controls. We measured sectorial and mean RNFL thickness in a 3.5-mm-diameter circular scan centered on the optic nerve head, using optical coherence tomography (Heidelberg Spectralis SD-OCT) in all participants. Multivariate linear regression was used for adjustments.

RESULTS

No patient had subclinical IIH corresponding to increased RNFL thickness. However, in obese individuals, global peripapillary RNFL was thinner than in controls (104 ± 6 μm versus 99 ± 12 μm, p = 0.005). Overall, RNFL thickness was superior in the control group for all sectors. The differences reached significance for the nasal, temporal, superior temporal, and inferior temporal sectors. These differences remained even after adjusting for possible confounders (hypertension, dyslipidemia, diabetes, age, sleep apnea syndrome, and sex).

CONCLUSIONS

Routine screening asymptomatic obese patients undergoing bariatric surgery for IIH using RNFL thickness was not clinically relevant in our study. However, we found that severe obesity is associated with neurodegeneration independently of the other components of the metabolic syndrome, what may justify future investigation on the need of monitoring these patients.

Accelerometry calibration in people with class II-III obesity: Energy expenditure prediction and physical activity intensity identification

BACKGROUND

Almost all accelerometer calibration studies were developed for non-obese people, which hampers an accurate prediction of energy expenditure (EE) and induces a misclassification of sedentary activity (SA) and physical activity intensities (PAI) in class II-III obese people.

RESEARCH QUESTION

The purpose of this study was to develop regression equations to predict EE and cut-points to classify SA and PAI in severe obese people based on several metrics obtained from hip and back accelerometer placement data.

METHODS

43 class II-III obese participants performed a protocol that included sitting and standing positions and walking at several speeds. During the protocol participants wore an accelerometer at hip and back, and respiratory gas exchange was measured by indirect calorimetry. Accelerometer metrics analyzed were: activity counts, mean amplitude deviation and euclidean norm minus one. EE was predicted through linear mixed models while cut-points to classify SA and PAI were obtained applying receiver operating characteristic curves. Leave-one-out cross-validation data was used to calculate Bland-Altman plots, prediction accuracy, Kappa statistic and percent agreement.

RESULTS

All prediction models presented a quadratic equation that had as predictors body mass and one of the accelerometer metrics. Predicted EE indicated a good agreement and a root mean square error below 1.02 kcal min^-1. Global classification agreement from developed cut-points was categorized as almost perfect with a percent agreement above 84 %. Prediction accuracy and classification agreement were similar among accelerometer metrics in each position and between them in hip and back placement.

SIGNIFICANCE

Hip and back accelerometer data collected in severe obese people allow to accurately estimate EE and to correctly classify SA and PAI. These results enable future studies to adopt appropriate regression equations and cut-points developed for class II-III obese people rather than those established for non-obese people.

Erratum to "Gastroenteropancreatic Neuroendocrine Neoplasia Characterization in Portugal: Results from the NETs Study Group of the Portuguese Society of Endocrinology, Diabetes and Metabolism"

[This corrects the article DOI: 10.1155/2019/4518742.].

Gastroenteropancreatic Neuroendocrine Neoplasia Characterization in Portugal: Results from the NETs Study Group of the Portuguese Society of Endocrinology, Diabetes and Metabolism

BACKGROUND

The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) has been increasing in the last five decades, but there is no large-scale data regarding these tumours in Portugal. We conducted a cross-sectional, multicentric study in main Portuguese centers to evaluate the clinical, pathological, and therapeutic profile of GEP-NENs.

METHODS

From November, 2012, to July, 2014, data from 293 patients diagnosed with GEP-NENs from 15 centers in Portugal was collected and registered in an online electronic platform.

RESULTS

Median age at diagnosis was 56.5 (range: 15-87) years with a preponderance of females (54.6%). The most frequent primary sites were the pancreas (31.1%), jejunum-ileum (24.2%), stomach (13.7%), and rectum (8.5%). Data regarding hormonal status was not available in most patients (82.3%). Stratified by the tumour grade (WHO 2010 classification), we observed 64.0% of NET G1, 24.7% of NET G2, and 11.3% of NEC. Poorly differentiated tumours occurred mainly in older patients (p = 0.017), were larger (p < 0.001), and presented more vascular (p = 0.004) and lymphatic (p = 0.001) invasion. At the time of diagnosis, 44.4% of GEP-NENs presented metastatic disease. Surgery (79.6%) and somatostatin analogues (30.7%) were the most frequently used therapies of GEP-NENs with reported grading.

CONCLUSION

In general, Portuguese patients with GEP-NENs presented similar characteristics to other populations described in the literature. This cross-sectional study represents the first step to establish a national database of GEP-NENs that may aid in understanding the clinical and epidemiological features of these tumours in Portugal.

Phenotypic heterogeneity of hereditary diffuse gastric cancer: report of a family with early-onset disease

BACKGROUND AND AIMS

The time course for the development of clinically significant hereditary diffuse gastric cancer (HDGC) is unpredictable. Little is known about the progression from preclinical, indolent lesions to widely invasive, aggressive phenotypes. Gastroendoscopy often fails to detect early lesions, and risk-reducing/prophylactic total gastrectomy (PTG) is the only curative approach. We present an HDGC family with early-onset disease in which clinical and histologic findings provided insight into the understanding of different HDGC phenotypes.

METHODS

The proband was diagnosed at age 18 years with widely invasive, metastatic DGC. CDH1 genetic testing identified a pathogenic, germline CDH1 variant (c.1901C>T, p.Ala634Val). Thirty family members were tested, and 15 CDH1 carriers were identified.

RESULTS

Six family members had PTG, with negative preoperative workup. The proband's 14-year-old sister is the youngest patient, reported to date, to have PTG after negative preoperative biopsy sampling. Intramucosal HDGC foci were detected in all PTG specimens (1-33). In contrast to the "indolent" phenotype of these foci, the aggressive DGC from the proband showed pleomorphic cells, absent E-cadherin expression, increased proliferation (Ki-67 index), and activation of oncogenic events (p53, pSrc and pStat3 overexpression). All family members had Helicobacter pylori gastritis. Cag-A-positive strains were detected in all specimens, except in the proband's sister.

CONCLUSIONS

HDGC is a heterogeneous disease regarding clinical behavior, endoscopic findings, histopathologic features, and immunophenotypic/molecular profile. The presence of bizarre, pleomorphic cells in endoscopic biopsy specimens is suggestive of advanced disease and should prompt clinical intervention. The involvement of a full multidisciplinary team is essential for the management of these patients.

Gallstones and Bariatric Surgery: To Treat or Not to Treat?

BACKGROUND

Obesity and rapid weight loss after bariatric surgery are risk factors for gallstone disease.

OBJECTIVES

The present study sought to evaluate the feasibility of selective concomitant cholecystectomy only in patients with symptomatic disease and study risk factors for the development of symptomatic gallstones after bariatric surgery.

METHODS

Between January 2010 and December 2012, 734 consecutive patients presenting to our institution underwent bariatric surgery. From these, 81 patients were excluded due to prior or concurrent cholecystectomy. The remaining 653 patients with in situ gallbladder were followed for 12 months and were clinically screened for symptomatic or complicated cholelithiasis. Clinical and demographic characteristics were compared at baseline and 12 months after surgery.

RESULTS

Of the 653 patients with in situ gallbladder, only 24 (3.3 %) developed symptomatic gallstones and only nine presented complicated disease. None of the patients with asymptomatic disease at the time of surgery progressed to symptomatic or complicated disease. Patients who developed symptomatic disease were not significantly different, although there was a trend toward longer obesity evolution, lower insulin levels, and lower hepatic enzymes level. A multivariate regression analysis revealed that patients with gastric sleeve were more likely to develop symptomatic gallstones.

CONCLUSIONS

Although further studies are required, the management of gallstones in morbidly obese patients should not be different from normal-weight patients. Therefore, performing a laparoscopic cholecystectomy only in symptomatic patients is an effective approach and asymptomatic gallstones should not be treated at the time of bariatric surgery.

Assessment of bariatric surgery efficacy on Obstructive Sleep Apnea (OSA)

A worldwide rise in weight and obesity is taking place, associated with an increase in several comorbid conditions, such as Obstructive Sleep Apnea (OSA). Bariatric surgery is an effective treatment approach for obesity, with resultant improvement in obesity-related comorbidities. However, the relationship between this type of treatment and OSA is not well established. This systematic review aims to assess and characterize the impact that different types of bariatric surgery have on obese OSA patients. 22 articles with stated preoperative apnea-hypopnea index (AHI), apnea index (AI) or respiratory disturbance index (RDI) were analyzed in this review. A significant improvement in AHI/AI/RDI occurred after surgery, in addition to the foreseeable reduction in body mass index (BMI). Moreover, almost every study stated a postoperative reduction of the AHI to < 20/h and/or a >50% postoperative reduction of AHI, with few exceptions. The interventions with a combined malabsorptive and restrictive mechanism, like roux-en-Y gastric bypass (RYGB), were more efficacious in resolving and improving OSA than purely restrictive ones, like laparoscopic adjustable gastric banding (LAGB). In conclusion, bariatric surgery has a significant effect on OSA, leading to its resolution or improvement, in the majority of cases, at least in the short/medium term (1-2 years). However, the different results must be interpreted with caution as there are many potential biases resulting from heterogeneous inclusion criteria, duration of follow-up, diagnostic methodology and assessed variables.

Laparoscopic Adjustable Gastric Band: Complications, Removal and Revision in a Portuguese Highly Differentiated Obesity Treatment Center

INTRODUCTION

Our objective is to determine which complications lead to reoperation, and the outcomes of reoperation using laparoscopic adjustable gastric banding, laparoscopic Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy at Centro Hospitalar de São João.

MATERIAL AND METHODS

Observational study. Patients included were aged 18 to 65 years at first gastric banding, underwent removal from March 21st 2007 to January 23rd 2014 and were subsequently converted to gastric banding, gastric bypass or sleeve gastrectomy. Women who got pregnant during the initial gastric banding follow-up and patients that performed more than one conversion were excluded.

RESULTS

A total of 103 patients were included. Fifteen underwent revision to gastric banding, 71 to gastric bypass and 17 to sleeve gastrectomy. Respectively, percentage of excess weight loss at 1 month were 1.9 ± 12.2% in 6 patients, 36.9 ± 18.2% in 49 patients and 27.1% (13.3 - 68.6) in 11 patients (laparoscopic adjustable-gastric banding-laparoscopic Roux-en-Y gastric bypass p < 0.001, laparoscopic adjustable-gastric banding-laparoscopic sleeve gastrectomy p = 0.002 and laparoscopic Roux-en-Y gastric bypass-laparoscopic sleeve gastrectomy p = 0.474). At 3 months there were 12.8% (5.7 - 84.8) in 6 patients, 44.8 ± 19.7% in 24 patients and 48 ± 20.1% in 8 patients (laparoscopic adjustable-gastric banding-laparoscopic Roux-en-Y gastric bypass p = 0.017, laparoscopic adjustable-gastric banding-laparoscopic sleeve gastrectomy p = 0.039 and laparoscopic Roux-en-Y gastric bypass-laparoscopic sleeve gastrectomy p = 0.691).

DISCUSSION

At revision, ages and body mass indices are higher than other studies. Gastric bypass is the preferred revision surgery, because combines restriction and malabsorption, surgeons have more experience and long term outcomes are better described.

CONCLUSIONS

The main indications for reoperation were inadequate weight loss (37.4%) and band slippage (30%). At short term, in our patients, gastric banding as a revision surgery was not effective, as opposed to gastric bypass and sleeve gastrectomy.

Beyond central adiposity: liver fat and visceral fat area are associated with metabolic syndrome in morbidly obese patients

BACKGROUND

Despite its widespread clinical use, both body mass index (BMI) and waist circumference have been reported as inaccurate methods to measure abdominal obesity. The main objective of this study was to determine the relation between visceral fat area and fatty liver infiltration with the expression of metabolic syndrome (MS) in morbidly obese patients.

METHODS

We recruited a random selection of 100 morbidly obese patients on pre-operative evaluation for bariatric surgery. A pre-operative CT slice at L4-L5 level, was performed to measure visceral fat and at T12 level to measure hepatic attenuation.

RESULTS

Patients with MS had lower hepatic attenuation values (median 49.9 vs 55.5HU; p = .018) and had more VAT (242 vs 172 cm(2);p = .001). Conventional measures (BMI: p = .729 and waist circumference: p = .356), were not useful in discriminating morbidly obese patients with MS. By multivariable logistic regression, fatty liver infiltration (OR = 5.3; p = .03) and age (OR = 1.08; p = .04) were the only factors independently related to the presence of MS. MS prevalence was 100%, 71% and 55%, respectively for patients with both fatty liver and visceral adiposity; one; or none of this findings (AUC - .715; p = .016).

CONCLUSION

CT scan seems to measure 2 important markers of MS: visceral adiposity and hepatic fatty infiltration. In morbidly obese patients, both visceral adiposity and hepatic fatty infiltration increase the risk for the presence of MS.

Fasting glycemia: a good predictor of weight loss after RYGB

BACKGROUND

Preoperative prediction of weight loss after Roux-en-Y gastric bypass (RYGB) could help surgeons in managing surgical lists and patients' expectations. The objective of this study was to understand if preoperative metabolic control might improve surgical results.

METHODS

Prospective cohort of 163 consecutive patients who underwent RYGB with at least 1 year of follow-up.

RESULTS

Most patients were female (90.2%), with a mean age of 38 (19-60) and a BMI of 46.0 (34.3-59.9) kg/m(2). After 12 months, the mean body mass index (BMI) was 29.7 kg/m(2) (21.5-39.9) with a corresponding percentage of excess weight lost (%EWL) of 78.8% and a percentage of weight loss (%WL) of 35.1%. Patients with the highest preoperative fasting blood glucose (FBG) were older (42 versus 36; P<.001); were more likely to have type 2 diabetes (T2 DM, 40% versus 6.8%; P<.001) and metabolic syndrome (89% versus 25%; P<.001), had a slightly higher BMI (30.8 versus 29.3 kg/m(2); P = .03), and had achieved a significantly lower %EWL and %WL at 12 months (72.5% versus 81.2%; P = .004; 33.2 versus 35.9%; P = .03, respectively). We observed a dose-response effect with increasing FBG (<85 mg/dL, 85-100 mg/dL, and ≥ 100 mg/dL, respectively), with 83.5%, 80.0%, and 72.5% (P = .009) of %EWL at 12 months. By multivariate logistic regression, initial BMI and FBG>100, were the only variables related (inversely) with the probability of achieving a %EWL>80 or %WL>35. This effect was not detected in patients receiving oral antidiabetic medications.

CONCLUSION

Higher preoperative FBG is independently related to a poorer weight loss 12 months after RYGB; this suggests the need to offer earlier surgical intervention for severely obese patients with impairment of glucose metabolism. The potential for less weight loss in patients with a higher FBG should not discourage RYGB, given the significant metabolic improvement after surgery.

Acute improvement in insulin resistance after laparoscopic Roux-en-Y gastric bypass: is 3 days enough to correct insulin metabolism?

BACKGROUND

Although medium- to long-term improvement in insulin resistance and T2DM after Roux-en-Y gastric bypass (RYGB) is well documented, few studies have analyzed the acute effects after surgery. Understanding these effects might help explain the physiologic adjustments after surgery and help in managing insulin resistance and controlling the hypoglycemic treatment for bariatric patients.

METHODS

We recruited a prospective cohort of 55 consecutive female patients that underwent primary laparoscopic RYGB between January and June/2011. Blood samples were collected preoperatively and at the first, third, and fifth post-operative days after an overnight fast.

RESULTS

There was a significant increase in homeostasis model assessment for insulin resistance (HOMA-IR) on day 1 (2.36 vs 3.12; p = 0.032), followed by a rapid decrease from day 3 onward (3.12 vs 1.70; <0.001). We found a statistically significant difference (p < 0.05) at all time points compared with baseline. HOMA-IR levels at POD5 were 47 % lower than baseline values and were not significantly different from values at 6 months (1.24 vs 0.93; p = 0.09). The blood levels of glucose and insulin closely matched those of HOMA-IR.

CONCLUSIONS

RYGB results in a rapid improvement in insulin resistance and a clinically significant decrease in fasting glucose and insulin levels. This improvement is significant at the 3rd post-operative day, and by the 5th day, patients express insulin resistance levels that are similar to those expressed at 6 months after surgery. This work highlights the acute metabolic impact of surgery. Understanding the behavior of insulin and glucose after surgery might improve our knowledge of the pathophysiology of diabetes and lead to novel therapies and tailored surgical approaches.

Petersen's space hernia: A rare but expanding diagnosis

BACKGROUND

Petersen's space hernia is caused by the herniation of intestinal loops through the defect between the small bowel limbs, the transverse mesocolon and the retroperitoneum, after any type of gastrojejunostomy. The laparoscopic approach facilitates the occurrence of this type of hernia, due to the lack of post-operative adhesions which prevent bowel motility and hence, herniation.

CASE REPORT

We report the case of a 46 year-old male submitted to an open antrectomy and vagotomy with a Roux-en-Y reconstruction six-years before, for the treatment of bleeding gastric ulcer.He presented with epigastric abdominal pain radiating to the back and alimentary vomiting with a 3 days evolution, with an episode of hematemesis 2 h before admission. His abdomen was bloated and tender at the epigastric region. The laboratory exams revealed mild leucocytosis and CRP elevation with normal pancreatic tests. The abdominal CT scan revealed an intestinal occlusion. An exploratory laparotomy was performed, disclosing an incarcerated Petersen space hernia of the common limb, with obstruction and dilatation of the biliary limb.

CONCLUSION

The knowledge of this anatomic post-operative defect and a low threshold for diagnosis are crucial to its management, since its nonspecific clinical and laboratory findings. Early operative intervention is warranted in order to avoid the severe complications of bowel necrosis.

Early gastric cancer: The importance of early diagnosis on prognosis of gastric carcinoma

29

Background: The aim of this study was to evaluate the characteristics of early gastric cancer (EGC) in comparison to advanced tumors and its role in patient's prognosis.

Methods: This study was related to 1,272 patients admitted with gastric or gastroesophageal junction carcinoma in our department, between January 1988 and December 2008. During this period the incidence of EGC was 12.68% (3.62% T0, 42.75% T1a and 53.62% T1b). Several clinical, pathological and staging parameters were evaluated according to classification in EGC and advanced tumors.

Results: Significant differences were observed in location (p<0.001); type of resection surgery (p<0.001) and of lymphadenectomy (p=0.008 for Siewert and p<0.001 for Japanese classifications) with less radical surgery in EGC patients. This type of tumors presented characteristics associated with a better prognosis in the following pathological parameters: tumor dimensions (p<0.001), macroscopic form (p<0.001), Ming's classification (p<0.001), venous invasion (p<0.001) and lymphatic permeation (p<0.001). The 5-year survival rate of this series was 33.7%. There were significant differences in survival curves according to classification in EGC and advanced tumors (73% at 5 years and 26% at 5 years, respectively). Cox-regression analysis identified age, T and lymph node ratio as independent prognostic factors. There was no significant differences in age (cut-off 45 years), but there was significant differences in lymph node metastasis (p<0.001). In 23.87% of EGC there was lymph node involvement, with significant differences (p=0.002) according to the depth wall invasion [T0 (100% N0), T1a (91.5% N0, 8.5% N1), T1b (60.8% N0, 21.6% N1, 13.5% N2, 4.1% N3a)].

Conclusions: The EGC percentage in our series was lower in comparison with other countries with high incidence of gastric cancer. The prognosis of the patients with gastric carcinoma continues to be gloomy mainly due to the late diagnosis and, given that the surgical treatment doesn't seem plausible of achieving a margin of significant additional progression, the need for an early diagnosis emerges if an improvement in patient survival is desired.

No significant financial relationships to disclose.

Early-onset gastric cancer: A distinct clinical entity with a different prognosis?

22

Background: This study aimed to evaluate the early onset gastric cancer (EOGC), considered as gastric cancer in a patient younger than 45 years, as a distinct entity with a different prognosis.

Methods: This study is related to 1,256 patients admitted with gastric or gastroesophageal junction carcinoma in our department between January 1988 and December 2008. There were 10.59% (133 cases) of EOGC in our series. The following clinical, pathological and staging parameters were studied: age, gender, tumor location, ressecability, type of resection surgery, type of resection, type of lymphadenectomy (Siewert and Japanese classifications), number of lymph nodes studied, tumor dimensions, macroscopic form, histological classification (Lauren and Ming), venous invasion, lymphatic permeation, perineural invasion, depth wall invasion (T), lymph node metastases (N) – TNM and Japanese classification and lymph node ratio – distance metastases (M) and stage.

Results: Significant differences were observed in the type of resection surgery (p<0.001) and type of lymphadenectomy (p=0.008), with more radical surgery performed in EOGC patients. Some tumor characteristics also showed significant differences: tumor dimensions (p=0.004), with EOGC usually smaller; diffuse type according to Lauren's classification (p<0.001); infiltrative type according to Ming's classification (p=0.001); less venous invasion (p=0.005); less lymphatic permeation (p=0.029). There were no significant differences in the staging parameters. There were significant differences in the survival rate (p<0.001), with 5-year survival rate of 44% in patients with EOGC compared with 31% in older patients. Cox-regression analysis revealed that age was an independent prognostic factor (HR 2,166, 1,133-4,139 CI 95%, p = 0.019), as well as depth wall invasion (T) and lymph node ratio.

Conclusions: In this study, EOGC revealed to be a distinct clinical entity that presented differences in various clinico-pathological parameters. Despite EOGC presented more aggressive pathological characteristics, there was a better survival in this group, probably because the physical status of younger patients which allowed a more aggressive treatment.

No significant financial relationships to disclose.

Malnutrition among hospitalized patients. A problem of physician awareness

Between 25% and 50% of patients admitted to an acute medical service are malnourished. Physicians are often unaware which patients are admitted at nutritional risk and make no attempt to arrest further nutritional decline until a dramatic deterioration has occurred. We studied all patients admitted to an acute medical ward service before and after their physicians were taught to recognize nutritional deficiency early and to intervene appropriately. During the initial period, the house staff correctly identified two (12.5%) of 16 patients as being malnourished. During the posteducation period, physicians correctly identified all 14 patients admitted at nutritional risk (100%), using a simple screening device that required only routine admission data. In all cases, the appropriate nutritional intervention was subsequently made. Results were further validated using a pretest and posttest, showing a significant improvement in nutritional knowledge. We conclude that physicians are not presently being taught to recognize malnutrition, that such malnutrition is latrogenically worsened in the hospital, and that physician education can effectively correct this problem.