Factors Associated with Weight Loss After Metabolic Surgery in a Multiethnic Sample of 1012 Patients

Body Composition Changes and Factors Influencing the Total Weight Loss Rate After Laparoscopic Sleeve Gastrectomy

Objectives: While the effectiveness of metabolic/bariatric surgery has been confirmed, understanding the factors associated with weight loss is paramount for providing guidance in postoperative treatment strategies. Here, we aimed to examine the factors associated with long-term maintenance of weight loss after laparoscopic sleeve gastrectomy (LSG). Methods: This prospective observational cohort included patients who underwent LSG at a single academic health center between January 2017 and June 2022. We examined their body composition using InBody 720 or 770 and analyzed the factors associated with the percentage of total weight loss (%TWL) for 24 months. Results: The median body mass index (BMI) was 38.8 (interquartile range [IQR]: 35.6-46.7) preoperatively, 32.7 kg/m2 (IQR: 28.2-38.7) at 12 months postoperatively, and 33.9 kg/m2 (IQR: 29.1-40.1) at 24 months postoperatively. The lowest BMI was observed at 12 months (p < 0.001 vs. preoperative), followed by a significant increase at 24 months (p = 0.003). However, BMI remained significantly lower at 24 months than preoperatively (p < 0.001). The skeletal muscle mass to fat mass ratio (SMM/FM) was 0.59 (IQR: 0.50-0.71) preoperatively, 0.79 (IQR: 0.58-1.26) at 12 months, and 0.70 (IQR: 0.54-1.05) at 24 months, peaking at 12 months (p < 0.001 vs. preoperative) and decreasing significantly by 24 months (p < 0.001). Nevertheless, the SMM/FM ratio at 24 months remained higher than preoperative values (p < 0.001). Median body weight and %TWL were 86.0 kg and 15.6%, respectively, at 24 months after LSG. The SMM/FM ratio at 12 months was positively correlated with %TWL at 24 months after adjusting for age and sex. Conclusions: The effects of LSG persisted for up to 24 months postoperatively. The SMM/FM ratio 12 months after LSG was associated with the rate of weight loss at 24 months.

Use of polygenic risk scores to assess weight loss after bariatric surgery: a 5-year follow-up study

BACKGROUND

Bariatric surgery (BS) is currently the most effective long-term treatment of severe obesity. However, the interindividual variability observed in surgical outcomes suggests a moderating effect of several factors, including individual genetic background. This study aimed to investigate the contribution of the genetic architecture of body mass index (BMI) to the variability in weight loss outcomes after BS.

METHODS

A total of 106 patients with severe obesity who underwent Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy were followed up for 5 years. Changes in BMI (BMIchange) and percentage of total weight loss (%TWL) were evaluated during the postoperative period. Polygenic risk scores (PRSs), including 50 genetic variants, were calculated for each participant to determine their genetic risk of high BMI based on a previous genome-wide association study. Generalized estimating equation models were used to study the role of the individual's polygenic score and other factors on BMIchange and %TWL in the long term after surgery.

RESULTS

This study found an effect of the polygenic score on %TWL and BMIchange, in which patients with lower scores had better outcomes after surgery than those with higher scores. Furthermore, when analyzing only patients who underwent RYGB, the results were replicated, showing greater weight loss after surgery for patients with lower polygenic scores.

DISCUSSION

Our results indicate that genetic background assessed with PRSs, along with other individual factors, such as biological sex, age, and preoperative BMI, has an effect on BS outcomes and could represent a useful tool for estimating surgical outcomes in advance.

Reduced Risk of Cardiovascular Diseases after Bariatric Surgery Based on the New PREVENT Equations

Background

We applied the novel Predicting Risk of Cardiovascular Disease EVENTs (PREVENT) equations to evaluate cardiovascular-kidney-metabolic (CKM) health and estimated CVD risk, including heart failure (HF), after bariatric surgery.

Methods

Among 7804 patients (20-79 years) undergoing bariatric surgery at Vanderbilt University Medical Center during 1999-2022, CVD risk factors at pre-surgery, 1-year, and 2-year post-surgery were extracted from electronic health records. The 10- and 30-year risks of total CVD, atherosclerotic CVD (ASCVD), coronary heart disease (CHD), stroke, and HF were estimated for patients without a history of CVD or its subtypes at each time point, using the social deprivation index-enhanced PREVENT equations. Paired t-tests or McNemar tests were used to compare pre- with post-surgery CKM health and CVD risk. Two-sample t-tests were used to compare CVD risk reduction between patient subgroups defined by age, sex, race, operation type, weight loss, and history of diabetes, hypertension, and dyslipidemia.

Results

CKM health was significantly improved after surgery with lower systolic blood pressure, non-high-density-lipoprotein cholesterol (non-HDL), and diabetes prevalence, but higher HDL and estimated glomerular filtration rate (eGFR). The 10-year total CVD risk decreased from 6.51% at pre-surgery to 4.81% and 5.08% at 1- and 2-year post-surgery (relative reduction: 25.9% and 16.8%), respectively. Significant risk reductions were seen for all CVD subtypes (i.e., ASCVD, CHD, stroke, and HF), with the largest reduction for HF (relative reduction: 55.7% and 44.8% at 1- and 2-year post-surgery, respectively). Younger age, White race, >30% weight loss, diabetes history, and no dyslipidemia history were associated with greater HF risk reductions. Similar results were found for the 30-year risk estimates.

Conclusions

Bariatric surgery significantly improves CKM health and reduces estimated CVD risk, particularly HF, by 45-56% within 1-2 years post-surgery. HF risk reduction may vary by patient's demographics, weight loss, and disease history, which warrants further research.

Assessing the predictive value of the suppressed 1 mg overnight dexamethasone suppression test in success of bariatric surgery

Bariatric surgery has been proven to be a successful intervention for managing obesity. There are numerous studies in the literature aiming to predict the factors influencing the success of bariatric surgery. Our study aims to determine whether preoperative 1 mg overnight dexamethasone suppression test (1 mg-DST) serum cortisol levels can serve as predictors of the effectiveness of bariatric surgery in severe obese patients without Cushing syndrome. A total of 98 patients who underwent bariatric surgery were included in the study. The preoperative 1 mg-DST levels, insulin levels, thyroid function tests, and lipid profiles of the patients were recorded. The patients' preoperative, postoperative 3rd, and 6th month weights were recorded and the percent total weight loss (%TWL) is calculated. Patients were categorized into 2 groups based on their TWL at 6 months. The 1 mg-DST results were significantly lower in the high-TWL-6 group (0.93 ± 0.37 μg/dL) compared to the low-TWL-6 group (1.09 ± 0.36 μg/dL, P = .040). Similarly, Homeostatic Model Assessment for Insulin Resistance values were lower in the high-TWL-6 group (5.63 ± 2.21) compared to the low-TWL-6 group (6.63 ± 2.55, P = .047). The optimal cutoff value found for 1 mg-DST level was 0.97 µg/dL, providing 50% sensitivity and 70% specificity. This study is the first to examine the predictive role of suppressed 1 mg-DST levels on postoperative weight loss in nondiabetic patients. The most prominent result of this study was that we observed a negative correlation between 1 mg-DST levels and %TWL.

Sex- and operation-dependent effects on 5-year weight loss results of bariatric surgery

BACKGROUND

Weight loss response after bariatric surgery is highly variable, and several demographic factors are associated with differential responses to surgery. Preclinical studies demonstrate numerous sex-specific responses to bariatric surgery, but whether these responses are also operation dependent is unknown.

OBJECTIVE

To examine sex-specific weight loss outcomes up to 5 years after laparoscopic Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

SETTING

Single center, university, United States.

METHODS

Retrospective, observational cohort study including RYGB (n = 5057) and vertical SG (n = 2041) patients from a single, academic health center. Percentage total weight loss (TWL) over time was examined with generalized linear mixed models to determine the main and interaction effects of surgery type on weight loss by sex.

RESULTS

TWL demonstrated a strong sex-by-procedure interaction, with women having a significant advantage with RYGB compared with SG (adjusted difference at 5 yr: 8.0% [95% CI: 7.5-8.5]; P < .001). Men also experienced greater TWL over time with RYGB or SG, but the difference was less and clinically insignificant (adjusted difference at 5 yr: 2.9% [2.0-3.8]; P < .001; P interaction between sex and procedure type = .0001). Overall, women had greater TWL than men, and RYGB patients had greater TWL than SG patients (adjusted difference at 5 yr: 3.1% [2.4-3.2] and 6.9% [6.5-7.3], respectively; both P < .0001). Patients with diabetes lost less weight compared with those without (adjusted difference at 5 yr: 3.0% [2.7-3.2]; P < .0001).

CONCLUSIONS

Weight loss after bariatric surgery is sex- and procedure-dependent. There is an association suggesting a clinically insignificant difference in weight loss between RYGB and SG among male patients at both the 2- and 5-year postsurgery time points.

Analysis of correlation between BMI and TWL% outcome following metabolic and bariatric surgery: a retrospective study using restricted cubic spline

OBJECTIVE

This study aimed to examine the correlation between preoperative body mass index (BMI) and adequate percentage of total weight loss (TWL%) outcome and present evidence of tiered treatment for patients with obesity in different preoperative BMI.

METHODS

We included patients with complete follow-up data who underwent metabolic and bariatric surgery (BMS). We termed optimal clinical response as TWL% >20% at one year following MBS. To investigate dose-response association between preoperative BMI and optimal clinical response, preoperative BMI was analyzed in three ways: (1) as quartiles; (2) per 2.5 kg/m2 units (3) using RCS, with 3 knots as recommended.

RESULTS

A total of 291 patients with obesity were included in our study. The corresponding quartile odds ratios associated with optimal clinical response and adjusted for potential confounders were 1.00 (reference), 1.434 [95% confidence interval (95%CI)   =  0.589-3.495], 4.926 (95%CI   =  1.538-15.772), and 2.084 (95%CI   =  0.941-1.005), respectively. RCS analysis showed a non-linear inverted U-shaped association between preoperative BMI and optimal clinical response (Nonlinear P   =  0.009). In spline analysis, when preoperative BMI was no less than 42.9 kg/m2, the possibility of optimal clinical response raised as preoperative BMI increased. When preoperative BMI was greater than 42.9 kg/m2, the possibility of optimal clinical response had a tendency to decline as preoperative BMI increased.

CONCLUSION

Our research indicated the non-linear inverted U-shaped correlation between preoperative BMI and adequate weight loss. Setting a preoperative BMI threshold of 42.9 is critical to predicting optimal clinical outcomes.

Machine Learning Model in Obesity to Predict Weight Loss One Year after Bariatric Surgery: A Pilot Study

Roux-en-Y gastric bypass (RYGB) is a treatment for severe obesity. However, many patients have insufficient total weight loss (TWL) after RYGB. Although multiple factors have been involved, their influence is incompletely known. The aim of this exploratory study was to evaluate the feasibility and reliability of the use of machine learning (ML) techniques to estimate the success in weight loss after RYGP, based on clinical, anthropometric and biochemical data, in order to identify morbidly obese patients with poor weight responses. We retrospectively analyzed 118 patients, who underwent RYGB at the Hospital Clínico Universitario of Valencia (Spain) between 2013 and 2017. We applied a ML approach using local linear embedding (LLE) as a tool for the evaluation and classification of the main parameters in conjunction with evolutionary algorithms for the optimization and adjustment of the parameter model. The variables associated with one-year postoperative %TWL were obstructive sleep apnea, osteoarthritis, insulin treatment, preoperative weight, insulin resistance index, apolipoprotein A, uric acid, complement component 3, and vitamin B12. The model correctly classified 71.4% of subjects with TWL < 30% although 36.4% with TWL ≥ 30% were incorrectly classified as "unsuccessful procedures". The ML-model processed moderate discriminatory precision in the validation set. Thus, in severe obesity, ML-models can be useful to assist in the selection of patients before bariatric surgery.

Cardiometabolic Improvements After Metabolic Surgery and Related Presurgery Factors

Context

Metabolic surgery remains the most effective and durable treatment for severe obesity and related metabolic diseases.

Objective

We examined cardiometabolic improvements after metabolic surgery and associated presurgery demographic and clinical factors in a large multiracial cohort.

Methods

Included were 7804 patients (20-79 years) undergoing first-time metabolic surgery at Vanderbilt University Medical Center from 1999 to 2022. Pre- and 1-year postsurgery cardiometabolic profiles were extracted from medical records, including body mass index (BMI), blood pressure, blood lipids, glucose, and hemoglobin A1c. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk was estimated per American College of Cardiology/American Heart Association equations. Pre- to postsurgery cardiometabolic profiles were compared by paired t-test, and associated factors were identified by multivariable linear and logistic regression.

Results

Among 7804 patients, most were women and White, while 1618 were men and 1271 were Black; median age and BMI were 45 years [interquartile range (IQR): 37-53] and 46.4 kg/m2 (IQR: 42.1-52.4). At 1-year postsurgery, patients showed significant decreases in systolic blood pressure (10.5 [95% confidence interval: 10.1, 10.9] mmHg), total cholesterol (13.5 [10.3, 16.7] mg/dL), glucose (13.6 [12.9, 14.4] mg/dL), hemoglobin A1c (1.13% [1.06, 1.20]), and 10-year ASCVD risk (absolute reduction: 1.58% [1.22, 1.94]; relative reduction: 34.4% [29.4, 39.3]); all P < .0001. Older, male, or Black patients showed less reduction in 10-year ASCVD risk and lower odds of diabetes/hypertension/dyslipidemia remission than younger, female, or White patients. Patients with a history of diabetes, hypertension, dyslipidemia, or cardiovascular disease showed less cardiometabolic improvements than those without. Results were similar with or without further adjusting for weight loss and largely sustained at 2-year postsurgery.

Conclusion

Metabolic surgery results in significant cardiometabolic improvements, particularly among younger, female, or White patients and those without comorbidities.

Follow-up after bariatric surgery: is it time to tailor it? Analysis of early predictive factors of 3-year weight loss predictors of unsuccess in bariatric patients

Bariatric surgery (BS) is the most effective treatment strategy for obesity. Nevertheless, a subset of patients does not reach a successful weight loss or experience long-term weight regain. Conflicting evidence exists regarding predictors of BS outcomes. We aimed to define the early factors linked to 3 year unsuccessful weight loss in order to promote a tailored close follow-up. We enrolled 443 patients who underwent BS from January 2014 to December 2018 with a 3 year follow-up. An unsuccessful BS outcome was defined as a percentage of total weight loss (%TWL) < 20. We compared the characteristics between successful and unsuccessful patients in order to identify predictor factors of unsuccess after surgery. We found that the proportion of patients with unsuccessful weight loss progressively increased from one to three years after BS. In a multiple regression model, only 1 month %TWL and sleeve gastrectomy (SG) were significantly associated with 3 year unsuccessful weight loss. We stratified our cohort in four groups according to the risk of BS unsuccess, in terms of 1 month %TWL and type of surgery (SG vs gastric bypass). Interestingly, groups showed a significant difference in terms of %TWL at each follow-up point. Patients submitted to SG with lower 1 month %TWL must be considered at higher risk of future weight regain; consequently, they require a tailored and closer follow-up.

Preoperative Prediction of Body Mass Index of Patients with Type 2 Diabetes at 1 Year After Laparoscopic Sleeve Gastrectomy: Cross-Sectional Study

Background: Very few models predict weight loss among type 2 diabetes mellitus (T2D) patients after laparoscopic sleeve gastrectomy (LSG). This retrospective study undertook such a task. Materials and Methods: We identified all patients >18 years old with T2D who underwent primary LSG at our institution and had complete data. The training set comprised 107 patients operated upon during the period April 2011 to June 2014; the validation set comprised 134 patients operated upon during the successive chronological period, July 2014 to December 2015. Sex, age, presurgery BMI, T2D duration, number of T2D medications, insulin use, hypertension, and dyslipidemia were utilized as independent predictors of 1-year BMI. We employed regression analysis, and assessed the goodness of fit and "Residuals versus Fits" plot. Paired sample t-tests compared the observed and predicted BMI at 1 year. Results: The model comprised preoperative BMI (β = 0.757, P = 0.026) + age (β = 0.142, P < 0.0001) with adjusted R² of 0.581 (P < 0.0001), and goodness of fit showed an unbiased model with accurate prediction. The equation was: BMI value 1 year after LSG = 1.777 + 0.614 × presurgery BMI (kg/m²) +0.106 × age (years). For validation, the equation exhibited an adjusted R² 0.550 (P < 0.0001), and the goodness of fit indicated an unbiased model. The BMI predicted by the model fell within -3.78 BMI points to +2.42 points of the observed 1-year BMI. Pairwise difference between the mean 1-year observed and predicted BMI was not significant (-0.41 kg/m², P = 0.225). Conclusions: This predictive model estimates the BMI 1 year after LSG. The model comprises preoperative BMI and age. It allows the forecast of patients' BMI after surgery, hence setting realistic expectations which are critical for patient satisfaction after bariatric surgery. An attainable target motivates the patient to achieve it.

Development and validation of a scoring system for pre-surgical and early post-surgical prediction of bariatric surgery unsuccess at 2 years

Bariatric surgery (BS) is an effective treatment for morbid obesity. However, a simple and easy-to-use tool for the prediction of BS unsuccess is still lacking. Baseline and follow-up data from 300 consecutive patients who underwent BS were retrospectively collected. Supervised regression and machine-learning techniques were used for model development, in which BS unsuccess at 2 years was defined as a percentage of excess-weight-loss (%EWL) < 50%. Model performances were also assessed considering the percentage of total-weight-loss (%TWL) as the reference parameter. Two scoring systems (NAG-score and ENAG-score) were developed. NAG-score, comprising only pre-surgical data, was structured on a 4.5-point-scale (2 points for neck circumference ≥ 44 cm, 1.5 for age ≥ 50 years, and 1 for fasting glucose ≥ 118 mg/dL). ENAG-score, including also early post-operative data, was structured on a 7-point-scale (3 points for %EWL at 6 months ≤ 45%, 1.5 for neck circumference ≥ 44 cm, 1 for age ≥ 50 years, and 1.5 for fasting glucose ≥ 118 mg/dL). A 3-class-clustering was proposed for clinical application. In conclusion, our study proposed two scoring systems for pre-surgical and early post-surgical prediction of 2-year BS weight-loss, which may be useful to guide the pre-operative assessment, the appropriate balance of patients' expectations, and the post-operative care.

Racial disparities in bariatric surgery postoperative weight loss and patient satisfaction

BACKGROUND

A growing body of evidence has demonstrated racial disparities in bariatric surgery (BS) outcomes. We aimed to investigate the impact of race on postoperative percent excess weight loss (%EWL) and patient satisfaction.

METHODS

Single center retrospective study of patients who underwent BS January 2012 to November 2017. Statistical analysis utilized Chi-squared, ANOVA and multivariable regression.

RESULTS

A total of 378 patients were included. African American patients lost significantly less weight compared to Caucasian and Hispanic patients (39.0 %EWL, 53.4 %EWL and 52.3 %EWL, respectively). A significant difference remained after adjustment for possible confounders. No difference in postoperative satisfaction was found.

CONCLUSIONS

Our study adds to the existing literature demonstrating racial disparities in BS postoperative EWL, despite adjusting for possible confounders, while contributing to the limited literature examining Hispanic patients. Furthermore, we examined an understudied outcome in postoperative patient satisfaction and found no racial disparity despite disparity in EWL.

Endoscopic intragastric balloon therapy for 15 years in Japan: Results of nationwide surveys

INTRODUCTION

Endoscopic intragastric balloon (IGB) placement has been performed in Japan since 2004. The nationwide surveys were repeatedly carried out to confirm the effectiveness and safety of IGB in Japan. We herein present the accumulated results.

METHODS

Twenty-six Japanese endoscopists personally imported products of the BioEnterics Intragastric Balloon (BIB)/Orbera system after completing the training courses in Japan. Mail surveys were posted to them every 2 years from 2010. This study included the accumulated data of the six surveys, and excluded data from non-Japanese patients and the Orbera365 data.

RESULTS

Between 2004 and 2019, 399 obese Japanese patients underwent IGB treatment using the BIB/Orbera system. The incidence rates of early removal of IGB within 1 week and complications due to IGB were 4.8% and 6.1%, respectively. The average percent excess weight loss (%EWL) and percent total weight loss (%TWL) at IGB removal were 46.6% and 11.5%, and successful weight loss, defined as %EWL ≥ 25% or %TWL ≥ 10%, was achieved in 65.6% or 54.5% of the patients, respectively. Multivariate analyses revealed that older age and larger saline filling volume were independent predictors of successful weight loss. At 1 year after IGB removal, successful weight loss defined by the %EWL and %TWL was maintained in 44.7% and 34.1% of the patients, respectively.

CONCLUSION

IGB therapy using the BIB/Orbera system has been safely and effectively performed in Japan. The successful weight loss may be associated with older age and larger saline filling volume.

Racial disparities in bariatric surgery postoperative weight loss and co-morbidity resolution: a systematic review

While bariatric surgery is an accepted treatment for morbid obesity, the impact of race on surgical outcomes remains unclear. This systematic review aims to compare differences in weight loss and co-morbidity outcomes among various races after bariatric surgery. PubMed, Medline, and SCOPUS databases were queried to identify publications that included more than 1 racial group and reported weight loss outcomes after bariatric surgery. A total of 52 studies were included. Non-Hispanic black (NHB) patients comprised between 5.5% and 69.7% and Hispanic patients comprised between 4.7% and 65.3% of the studies' populations. Definitions of weight loss success differed widely across studies, with percent excess weight loss being the most commonly reported outcome, followed by percent total weight loss and change in body mass index (BMI). Statistical analyses also varied, with most studies adjusting for age, sex, preoperative weight, or BMI. Some studies also adjusted for preoperative co-morbidities, including diabetes mellitus, hypertension, and hyperlipidemia, or socioeconomic status, including income, education, and neighborhood poverty. The majority of studies found less favorable weight loss in NHB compared to Hispanic and non-Hispanic white (NHW), patients while generally no difference was found between Hispanic and NHW patients. The trend also indicates no association between race and resolution of obesity-related co-morbidities. Racial minorities lose less weight than NHW patients after bariatric surgery, although the factors associated with this discrepancy are unclear. The heterogeneity in reporting weight loss success and statistical analyses amongst the literature makes an estimation of effect size difficult. Generally, racial disparity was not seen when examining co-morbidity resolution after surgery. More prospective, robust, long-term studies are needed to understand the impacts of race on bariatric surgery outcomes and ensure successful outcomes for all patients, regardless of race.

What predicts the unsuccess of bariatric surgery? An observational retrospective study

PURPOSE

Bariatric surgery (BS) has been recognized as an effective treatment for most patients with morbid obesity, but a variable range of patients failed to achieve a successful weight-loss. Controversial data are available about predictors of unsuccess. We aimed to retrospectively assess whether clinical baseline characteristics of patients submitted to sleeve gastrectomy (SL) or gastric bypass (GBP) were associated with unsuccessful weight-loss after 12 and 24-month follow-up.

METHODS

Three hundred patients who underwent BS from the 1st January 2016, with at least 24-months follow-up, were enrolled. Patients were divided according to their percentage of excess weight-loss (%EWL) either < 50% or ≥ 50% after 12 and 24-month follow-up.

RESULTS

None of the patients was lost at follow-up; 56 (18.7%) patients showed a %EWL < 50% at 24 months. Age, neck circumference, obstructive sleep apnea (OSA) were significantly higher, while total cholesterol and %EWL 6-months lower in those with %EWL < 50% at 12-months. Age, neck circumference, male and OSA rates were increased, while %EWL at 6-months lower in patients with %EWL < 50% at 24-months. In a multiple regression model, age (OR = 1.076; 95% CI 1.029-1.125; p = 0.001; OR = 1.066; 1.027-1.107; p < 0.001) and %EWL at 6-months (OR = 0.876; 0.840-0.913; p < 0.001; OR = 0.950; 0.928-0.972; p < 0.001) were associated with %EWL < 50% both at 12- and 24-months, respectively, and neck circumference (OR = 1.142; 1.011-1.289; p = 0.032) with %EWL < 50% at 24-months.

CONCLUSION

Older age, larger neck circumference, and %EWL at 6-months were significantly associated with BS unsuccess, showing almost 90% of those patients an unsuccessful weight-loss early after surgery. Further larger studies with longer follow-up are needed to confirm these results.

Six-year bariatric surgery outcomes: the predictive and incremental validity of presurgical psychological testing

BACKGROUND

Research identifying preoperative psychosocial predictors of bariatric surgery outcomes has yielded inconsistent results with minimal examination of longer-term outcomes. Utilizing a broadband measure of personality and psychopathology during the preoperative evaluation helps to identify preoperative risk factors for suboptimal bariatric surgery outcomes.

OBJECTIVE

Examine predictors of outcome and the incremental contribution of presurgical psychological testing to various long-term bariatric surgery outcomes.

SETTING

Academic medical center.

METHOD

A total of 168 postoperative patients (average of 6 postoperative years) consented to participate in the outcome study. Participants were weighed by the trained research/clinical staff and completed a battery of self-report questionnaires, including measures assessing eating attitudes and behaviors and weight-related quality-of-life (QoL). Patients had completed the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) as part of the institution's routine preoperative psychosocial evaluation. Weight loss was calculated as percent total weight loss (%TWL) and percent weight regain (%WR) was calculated as a percentage of maximum weight loss. Other preoperative data were obtained from a review of each patient's electronic medical record (EMR). From the initial sample, 145 patients were retained for analyses in the present study.

RESULTS

Preoperative problematic eating variables predicted long-term postoperative problematic eating behaviors and body image concerns. Scores on preoperative MMPI-2-RF scales measuring Demoralization, Dysfunctional Negative Emotions, Antisocial Behaviors, and Hypomanic Activation were consistent incremental predictors of 6-year outcomes, accounting for an additional 3%-24% of the variability in postoperative eating behaviors and QoL.

CONCLUSIONS

The preoperative psychological evaluation can be used to identify predictors of long-term bariatric surgery outcomes. Identification of these risk factors provides important targets for pre- and postoperative clinical interventions to maximize surgical outcomes.

Nomograms for Predicting Non-remission in Patients Who Underwent Bariatric Surgery: A Multicenter Retrospective Study in China

BACKGROUND

As a reflection of the increasing global incidence of obesity, there is a corresponding increase in the proportion of obese patients undergoing bariatric surgery. This study reviewed the factors and outcomes of patients who underwent bariatric surgical procedures and determined the relationships and developed a nomogram to calculate individualized patient risk.

METHODS

The nomogram was based on a retrospective study on 259 patients who underwent bariatric surgery at the Chengdu Third People's Hospital from June 2017 to June 2019. The predictive accuracy and discriminative ability of the nomogram were determined by the ROC curve and C-index, respectively. The results were validated using bootstrap resampling and a retrospective study on 121 patients operated on from May 2015 to May 2019 at the Tenth People's Hospital of Shanghai.

RESULTS

The predictors contained in the prediction nomogram included age, sex, surgical approach, hyperlipidemia, blood pressure (BP), hyperuricemia, body mass index (BMI), and waist circumference (WC). The 6-month model displayed good discrimination with a C-index of 0.765 (95% CI: 0.756 to 0.774) and good calibration. The 1-year model reached a C-index of 0.768 (95% CI, 0.759 to 0.777) in the training cohort.

CONCLUSIONS

The proposed nomogram resulted in more accurate non-remission prediction for patients with obesity after bariatric surgery and may provide a reference for the preoperative choice of surgical methods.

Relationship of estrogen synthesis capacity in the brain with obesity and self-control in men and women

Gonadal hormones are linked to mechanisms that govern appetitive behavior and its suppression. Estrogens are synthesized from androgens by the enzyme aromatase, highly expressed in the ovaries of reproductive-aged women and in the brains of men and women of all ages. We measured aromatase availability in the amygdala using positron emission tomography (PET) with the aromatase inhibitor [¹¹C]vorozole in a sample of 43 adult, normal-weight, overweight, or obese men and women. A subsample of 27 also completed personality measures to examine the relationship between aromatase and personality traits related to self-regulation and inhibitory control. Results indicated that aromatase availability in the amygdala was negatively associated with body mass index (BMI) (in kilograms per square meter) and positively correlated with scores of the personality trait constraint independent of sex or age. Individual variations in the brain's capacity to synthesize estrogen may influence the risk of obesity and self-control in men and women.

Outcomes of Bariatric Surgery in African Americans: an Analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Data Registry

Background

The incidence of obesity is disproportionally high in African Americans (AA) in the United States. This study compared outcomes for AA patients undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) with non-AA patients.

Methods

The MBSAQIP database was reviewed for RYGB and SG patients (2015–2017). Patients were identified as AA or non-AA and grouped to RYGB or SG. Combined and univariate analyses were performed on unmatched/propensity matched populations to assess outcomes.

Results

After applying exclusion criteria, 75,409 AA and 354,305 non-AA patients remained. Univariate analysis identified AA-RYGB and AA-SG patients were heavier and younger than non-AA patients. Overall, AA patients tended to have fewer preoperative comorbidities than non-AA patients with the majority of AA comorbidities related to hypertension and renal disease. Analysis of propensity matched data confirmed AA bariatric surgery patients had increased cardiovascular-related disease incidence compared with non-AA patients. Perioperatively, AA-RYGB patients had longer operative times, increased rates of major complications/ICU admission, and increased incidence of 30-day readmission, re-intervention, and reoperation, concomitant with lower rates of minor complications/superficial surgical site infection (SSI) compared with non-AA patients. For SG, AA patients had longer operative times and higher rates of major complications and 30-day readmission, re-intervention, and mortality, coupled with fewer minor complications, superficial/organ space SSI, and leak.

Conclusion

African American patients undergoing bariatric surgery are younger and heavier than non-AA patients and present with different comorbidity profiles. Overall, AAs exhibit worse outcomes following RYGB or SG than non-AA patients, including increased mortality rates in AA-SG patients.