Pre-operative body shape concerns moderate excess weight loss trajectory in bariatric surgery patients: a 2-year longitudinal study.

PURPOSE: The main research aim was to inspect whether pre-operative body shape concerns and discomfort as Body Shape Questionnaire (BSQ) scores moderate post-operative weight loss trajectory in bariatric patients. METHODS: Two studies were conducted. Study 1 analyzed cross-sectional data and verified the structural validity of the 34-item BSQ questionnaire on a sample of 327 candidates for bariatric surgery. Study 2 examined longitudinal data, with objective Body Mass Index (BMI) recorded every 6 months, from surgery intervention on, with 5 measurement occasions, from 111 patients who initially completed BSQ as bariatric surgery candidates and then underwent periodic medical post-operative follow-ups, over 2 years. RESULTS: In Study 1, confirmatory factor analysis of a single-dimension model yielded acceptable fit indices and high internal consistency levels. Study 2 showed that post-operative excess BMI reduction trend was not linear and pre-operative BSQ scores moderated it, with a higher risk of weight regain in patients who initially were less concerned with their body shape. CONCLUSIONS: The present findings support the structural validity of the BSQ questionnaire in bariatric candidates and call attention on the role of pre-operative body shape concerns on post-operative weight loss trajectories over 2 years, in accordance with a pathoplasty model. They suggest the need for systematic attention on perceived body image and psychological paths aimed to help bariatric patients regain positive attitudes towards their own body. Level of evidence III, well-designed cohort.

Tissue-specific inflammation and insulin sensitivity in subjects with obesity.

Obesity is associated with low-grade inflammation and insulin resistance (IR). The contribution of adipose tissue (AT) and hepatic inflammation to IR remains unclear. We conducted a study across three cohorts to investigate this relationship. The first cohort consists of six women with normal weight and twenty with obesity. In women with obesity, we found an upregulation of inflammatory markers in subcutaneous and visceral adipose tissue, isolated AT macrophages, and the liver, but no linear correlation with tissue-specific insulin sensitivity. In the second cohort, we studied 24 women with obesity in the upper vs lower insulin sensitivity quartile. We demonstrated that several omental and mesenteric AT inflammatory genes and T cell-related pathways are upregulated in IR, independent of BMI. The third cohort consists of 23 women and 18 men with obesity, studied before and one year after bariatric surgery. Weight loss following surgery was associated with downregulation of multiple immune pathways in subcutaneous AT and skeletal muscle, alongside notable metabolic improvements. Our results show that obesity is characterised by systemic and tissue-specific inflammation. Subjects with obesity and IR show a more pronounced inflammation phenotype, independent of BMI. Bariatric surgery-induced weight loss is associated with reduced inflammation and improved metabolic health.

Impact of bariatric surgery on anthropometric, metabolic, and reproductive outcomes in polycystic ovary syndrome: a systematic review and meta-analysis.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in females. Modest weight loss improves reproductive and metabolic PCOS features. While lifestyle modifications and pharmacotherapies remain first-line weight loss strategies, bariatric surgery is emerging as a potentially effective treatment. We performed a systematic review and meta-analysis of published literature to examine the impact of bariatric surgery in PCOS to inform the 2023 International PCOS Evidence-based Guidelines. Electronic databases were searched for observational studies and trials comparing pharmacologic or lifestyle treatments to bariatric surgery in women with PCOS or bariatric surgery in women with or without PCOS. Anthropometric, reproductive, hormonal, and metabolic outcomes were included and, where possible, meta-analyzed using random-effects models. Risk of bias and evidence quality were assessed. Ten studies were included involving 432 women with and 590 women without PCOS. Comparisons between bariatric surgery and pharmacologic or lifestyle treatments were only reported in one study each, and most reproductive outcomes were limited to a single study; therefore, meta-analyses could not be performed. Meta-analysis found that women with PCOS experience similar improvements in anthropometric, hormonal, and metabolic outcomes after bariatric surgery compared to those without PCOS. Existing research is limited and of low quality with high risk of bias, especially in comparison to existing PCOS treatments and with respect to reproductive outcomes including pregnancy, highlighting the need for additional studies to inform clinical recommendations.

Evaluation study of single-anastomosis duodenal-ileal bypass with sleeve gastrectomy in the treatment of Chinese obese patients based on efficacy and nutrition.

To evaluate the efficacy and nutrition of single-anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S) in Chinese obese patients in the first postoperative year. Clinical data of 66 obese patients who underwent SADI-S surgery at China-Japan Union Hospital of Jilin University from November 2018 to May 2022 were retrospectively collected. The weight, body mass index (BMI), percentage of excess weight loss (%EWL), and percentage of total weight loss (%TWL) were recorded at 3, 6, and 12 months after surgery. Moreover, metabolic disease remission and nutrient deficiencies were assessed at 1 year postoperatively. Overall, 66 patients (38 males and 28 females) were recruited, with a mean age of 35 (18-61) years and an average preoperative BMI of 42.94 kg/m2. Before surgery, 38 patients had type 2 diabetes mellitus (T2DM), 46 patients had hyperuricemia (HUA), 45 patients had hypertension (HTN), 35 patients had hyperlipidemia, 12 patients had hypercholesterolemia, 12 patients had hyper-low-density lipoproteinemia, and 14 patients had gastroesophageal reflux disease symptoms (GERD). All patients had undergone a DaVinci robotic or laparoscopic SADI-S surgery, and none converted to laparotomy or died. Four patients developed postoperative complications and were cured and discharged after conservative treatment or surgical treatment. At 3, 6 and 12 months, the average %EWL was 62.07 ± 26.56, 85.93 ± 27.92, and 106.65 ± 29.65%, %TWL was 22.67 ± 4.94, 32.10 ± 5.18, and 40.56 ± 7.89%, respectively. Fasting blood glucose (FBG), glycated hemoglobin (HbA1c), uric acid (UA), triglycerides (TG), blood pressure (BP), and other indexes were significantly lower after one year post-surgery compared with the preoperative period (P < 0.05). The remission rates of T2DM, HUA, HTN, hypertriglyceridemia, hypercholesterolemia, and hyper-low-density lipoproteinemia 1 year after surgery were 100, 65.2, 62.2, 94.3, 100, and100%, respectively. One year after surgery, the remission rate of GERD was 71.4% (10/14), the rate of new occurrence of GERD was 12.1% (8/66), and the overall incidence rate was 18.2% (12/66). Except for vitamin B12(vit B12), the other nutrient indexes were significantly decreased after 1 year of surgery relative to levels before surgery (P < 0.05). The deficiency rates for vitamin A (vit A), vitamin E (vit E), zinc ion (Zn), and folic acid (FA) were higher (45.5, 25.8, 24.2, and 16.7%, respectively); however, there were no related clinical symptoms. SADI-S had significant effects on weight loss and metabolic disease remission. The main nutrient deficiencies after SADI-S were vit A, vit E, Zn, and FA deficiencies. The long-term efficacy and safety of SADI-S warrant further follow-up.

Weight loss response to semaglutide in postmenopausal women with and without hormone therapy use.

OBJECTIVE: To compare weight loss response and changes in cardiometabolic risk markers in postmenopausal women using semaglutide with and without menopause hormone therapy (HT) use. METHODS: Retrospective cohort study of postmenopausal women treated with semaglutide for overweight or obesity for ≥3 months. Endpoints: total body weight loss percentage (TBWL%) at 3, 6, 9, and 12 months after semaglutide initiation; and percentage of women achieving ≥5% and ≥10% TBWL and changes in cardiometabolic risk markers (glucose, blood pressure, and lipids) at 12 months. RESULTS: There were 16 women on HT and 90 on no-HT; mean age 56 ± 8 vs 59 ± 8 yr, P = 0.2 and mean BMI 36 ± 5 vs 39 ± 8 kg/m 2 , P = 0.1; respectively. Among women on no-HT, White race, dyslipidemia, and depression were more prevalent. Women on HT had a higher TBWL% at 3, 6, 9, and 12 months: 7 ± 3% vs 5 ± 4%, P = 0.01; 13 ± 6% vs 9 ± 5%, P = 0.01; 15 ± 6% vs 10 ± 6%, P = 0.02; and 16 ± 6% vs 12 ± 8%, P = 0.04; respectively. After adjusting for potential confounders, this association remained significant across time. At 12 months, a greater percentage of women on HT achieved ≥5% and ≥10% TBWL. Both groups experienced an improvement in cardiometabolic risk markers. CONCLUSION: In postmenopausal women with overweight or obesity treated with semaglutide, HT use was associated with an improved weight loss response. This association was maintained when adjusted for confounders. Larger studies should be conducted to confirm these results.

Control of Eating Attributes and Weight Loss Outcomes over One Year After Sleeve Gastrectomy.

PURPOSE: Sleeve gastrectomy (SG) is a commonly performed metabolic-bariatric surgery, but its effectiveness is variable and difficult to predict. Our study aimed to compare control of eating (CoE) attributes pre- and post-SG depending on the achievement of optimal weight loss target at 1 year post-SG. MATERIALS AND METHODS: A prospective longitudinal cohort study using the CoE Questionnaire, pre-SG, and postoperatively at 3, 6, and 12 months was conducted. Total weight loss (TWL) ≥ 25% at 12 months post-SG was set as an optimal weight loss target. RESULTS: Forty-one patients (80.5% females, mean age 41.7 ± 10.6) were included. Sex, age, baseline weight, BMI, and smoking status were all comparable. At 3 months post-SG, "difficulty to control eating" score became significantly different between ≥ 25%TWL and < 25%TWL groups (7 [0-50] vs. 17 [5-63], p = 0.042). At 6 months, it was followed by "feeling of fullness," "frequency of food cravings," and "difficulty to resist cravings" demonstrating significant differences between ≥ 25%TWL and < 25%TWL groups. At 12 months, significant differences between groups were observed in "feeling hungry," "difficulty to resist cravings," "eating in response to cravings," and difficulty to control eating scores. CONCLUSION: Individuals with obesity who achieved a target of ≥ 25%TWL at 1 year post-SG have an early improvement in overall eating control at 3 months that steadily persists at 6 and 12 months. Improvements in other aspects tend to follow later, at 6 and 12 months. These findings may assist in identifying individuals with inadequate response to help attain optimal weight loss targets and developing a prognostic model to identify predictors of successful weight loss.

Sex differences in insulin regulation of skeletal muscle glycogen synthase and changes during weight loss and exercise in adults.

OBJECTIVE: The authors sought to understand sex differences in muscle metabolism in 73 older men and women. METHODS: Body composition, VO2max, and insulin sensitivity (M) by 3-hour hyperinsulinemic-euglycemic clamp with vastus lateralis muscle biopsies were measured. RESULTS: Women had lower body weight, VO2max, and fat-free mass than men. Men had lower M, lower change (insulin minus basal) in muscle glycogen synthase (GS) activity, and lower change in AKT protein expression than women. M was associated with the change (insulin-basal) in GS activity and the change in AKT protein expression. Sex differences (n = 60) were tested with 6-month weight loss or 3×/week aerobic exercise training. The postintervention minus preintervention change (insulin-basal) (∆∆) in GS activity (fractional, independent, total) was higher in men than women in the weight loss group and ∆∆ in GS fractional activity was higher in women than men in the aerobic exercise group. In all participants, ∆∆ in GS fractional and independent activities was related to ∆∆ in AKT expression and glycogen content. CONCLUSIONS: Sex differences in insulin sensitivity may be explained at the cellular muscle level, and to improve skeletal muscle insulin action in older adults, it may be necessary to recommend different behavioral strategies depending on the individual's sex.

Characteristics of changes in plasma proteome profiling after sleeve gastrectomy.

Bariatric surgery (BS), recognized as the most effective intervention for morbid obesity and associated metabolic comorbidities, encompasses both weight loss-dependent and weight loss-independent mechanisms to exert its metabolic benefits. In this study, we employed plasma proteomics technology, a recently developed mass spectrometric approach, to quantitatively assess 632 circulating proteins in a longitudinal cohort of 9 individuals who underwent sleeve gastrectomy (SG). Through time series clustering and Gene Ontology (GO) enrichment analysis, we observed that complement activation, proteolysis, and negative regulation of triglyceride catabolic process were the primary biological processes enriched in down-regulated proteins. Conversely, up-regulated differentially expressed proteins (DEPs) were significantly associated with negative regulation of peptidase activity, fibrinolysis, keratinocyte migration, and acute-phase response. Notably, we identified seven proteins (ApoD, BCHE, CNDP1, AFM, ITIH3, SERPINF1, FCN3) that demonstrated significant alterations at 1-, 3-, and 6-month intervals post SG, compared to baseline. These proteins play essential roles in metabolism, immune and inflammatory responses, as well as oxidative stress. Consequently, they hold promising potential as therapeutic targets for combating obesity and its associated comorbidities.

Obesity surgery and neural correlates of human eating behaviour: A systematic review of functional MRI studies.

Changes in eating behaviour including reductions in appetite and food intake, and healthier food cue reactivity, reward, hedonics and potentially also preference, contribute to weight loss and its health benefits after obesity surgery. Functional magnetic resonance imaging (fMRI) has been increasingly used to interrogate the neural correlates of eating behaviour in obesity, including brain reward-cognitive systems, changes after obesity surgery, and links with alterations in the gut-hormone-brain axis. Neural responses to food cues can be measured by changes in blood oxygen level dependent (BOLD) signal in brain regions involved in reward processing, including caudate, putamen, nucleus accumbens, insula, amygdala, orbitofrontal cortex, and top-down inhibitory control, including dorsolateral prefrontal cortex (dlPFC). This systematic review aimed to examine: (i) results of human fMRI studies involving obesity surgery, (ii) important methodological differences in study design across studies, and (iii) correlations and associations of fMRI findings with clinical outcomes, other eating behaviour measures and mechanistic measures. Of 741 articles identified, 23 were eligible for inclusion: 16 (69.6%) longitudinal, two (8.7%) predictive, and five (21.7%) cross-sectional studies. Seventeen studies (77.3%) included patients having Roux-en-Y gastric bypass (RYGB) surgery, six (26.1%) vertical sleeve gastrectomy (VSG), and five (21.7%) laparoscopic adjustable gastric banding (LAGB). The majority of studies (86.0%) were identified as having a very low risk of bias, though only six (27.3%) were controlled interventional studies, with none including randomisation to surgical and control interventions. The remaining studies (14.0%) had a low risk of bias driven by their control groups not having an active treatment. After RYGB surgery, food cue reactivity often decreased or was unchanged in brain reward systems, and there were inconsistent findings as to whether reductions in food cue reactivity was greater for high-energy than low-energy foods. There was minimal evidence from studies of VSG and LAGB surgeries for changes in food cue reactivity in brain reward systems, though effects of VSG surgery on food cue reactivity in the dlPFC were more consistently found. There was consistent evidence for post-operative increases in satiety gut hormones glucagon-like-peptide 1 (GLP-1) and peptide YY (PYY) mediating reduced food cue reactivity after RYGB surgery, including two interventional studies. Methodological heterogeneity across studies, including nutritional state, nature of food cues, post-operative timing, lack of control groups for order effects and weight loss or dietary/psychological advice, and often small sample sizes, limited the conclusions that could be drawn, especially for correlational analyses with clinical outcomes, other eating behaviour measures and potential mediators. This systematic review provides a detailed data resource for those performing or analysing fMRI studies of obesity surgery and makes suggestions to help improve reporting and design of such studies, as well as future directions.

Association of postoperative dietary macronutrient content and quality with total weight loss and fat-free mass loss at midterm after sleeve gastrectomy.

OBJECTIVES: This study aimed to investigate the associations of macronutrient quantities and qualities with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss in adults undergoing sleeve gastrectomy. METHODS: This cross-sectional study included 146 patients on postoperative time since sleeve gastrectomy of 2 to 4 y. Diet was assessed using a food frequency questionnaire. Macronutrient quality index, carbohydrate quality index, fat quality index, and healthy plate protein quality index were calculated. The associations of dietary variables with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss were determined using linear regression. Logistic regression was used to estimate the odds of non-response (percentage total weight loss < 25%) and excessive fat-free mass loss (percentage of fat-free mass loss relative to total weight loss > 28%) based on dietary intakes. RESULTS: Forty-six (31.5%) were non-responders, and 49 (33.6%) experienced excessive fat-free mass loss. The fully adjusted model showed a 0.75 decrease in percentage total weight loss per 5% carbohydrate increase (95% CI, -1.45 to -0.05). The odds of non-response were 53% lower per 5% increase in protein (95% CI, 0.23-0.94). Each 5-g higher intake of fat was associated with 0.29 higher percentage of fat-free mass loss relative to total weight loss (95% CI, 0.03-0.55). The odds of excessive fat-free mass loss were reduced by 5% per gram of fiber intake (95% CI, 0.90-0.99). Each 5% increment in energy intake from protein that was isocalorically substituted for either carbohydrate or fat was associated with lower odds of nonresponse. Macronutrient quality indices had no significant associations. CONCLUSIONS: Adherence to a high-protein, high-fiber diet after sleeve gastrectomy may enhance surgical success by improving total weight loss and preventing excessive fat-free mass loss.

Beyond Weight Loss: the Emerging Role of Incretin-Based Treatments in Cardiometabolic HFpEF.

PURPOSE OF REVIEW: Incretin-based drugs are potent weight-lowering agents, emerging as potential breakthrough therapy for the treatment of obesity-related phenotype of heart failure with preserved ejection fraction (HFpEF). In this review article, we will discuss the contribution of weight loss as part of the benefits of incretin-based medications in obese patients with HFpEF. Furthermore, we will describe the potential effects of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonists on the heart, particularly in relation to HFpEF pathophysiology. RECENT FINDINGS: In the STEP-HFpEF trial, the GLP-1 receptor agonist semaglutide significantly improved quality of life outcomes in obese HFpEF patients. Whether the beneficial effects of semaglutide in obese patients with HFpEF are merely a consequence of body weight reduction is unclear. Considering the availability of other weight loss strategies (e.g., caloric restriction, exercise training, bariatric surgery) to be used in obese HFpEF patients, answering this question is crucial to provide tailored therapeutic options in these subjects. SUMMARY: Incretin-based drugs may represent a milestone in the treatment of obesity in HFpEF. Elucidating the contribution of weight loss in the overall benefit observed with these drugs is critical in the management of obese HFpEF patients, considering that other weight-lowering strategies are available and might represent potential alternative options for these patients.

Plasma SHBG Levels as an Early Predictor of Response to Bariatric Surgery.

BACKGROUND: Obesity is a growing global health problem, and currently, bariatric surgery (BS) is the best solution in terms of sustained total weight loss (TWL). However, a significant number of patients present weight regain (WR) in time. There is a lack of biomarkers predicting the response to BS and WR during the follow-up. Plasma SHBG levels, which are low in obesity, increase 1 month after BS but there is no data of plasma SHBG levels at long term. We performed the present study aimed at exploring the SHBG role in predicting TWL and WR after BS. METHODS: Prospective study including 62 patients with obesity undergoing BS. Anthropometric and biochemical variables, including SHBG were analyzed at baseline, 1, 6, 12, and 24 months; TWL ≥ 25% was considered as good BS response. RESULTS: Weight loss nadir was achieved at 12 months post-BS where maximum SHBG increase was reached. Greater than or equal to 25% TWL patients presented significantly higher SHBG increases at the first and sixth months of follow-up with respect to baseline (100% and 150% respectively, p = 0.025), than < 25% TWL patients (40% and 50% respectively, p = 0.03). Also, these presented 6.6% WR after 24 months. The first month SHBG increase predicted BS response at 24 months (OR = 2.71; 95%CI = [1.11-6.60]; p = 0.028) and TWL in the 12th month (r = 0.330, p = 0.012) and the WR in the 24th (r = - 0.301, p = 0.028). CONCLUSIONS: Our results showed for the first time that increase in plasma SHBG levels within the first month after BS is a good predictor of TWL and WR response after 2 years.

Nutritional Considerations for Patients With Renal Failure Undergoing Sleeve Gastrectomy.

Obesity is highly prevalent in patients with renal disease, as it contributes to or accelerates the progression of kidney disease and is frequently a barrier to kidney transplantation. Patients with renal disease have unique dietary needs due to various metabolic disturbances resulting from altered processing and clearance of nutrients. They also frequently present with physical disability, resulting in difficulty achieving adequate weight loss through lifestyle modifications. Therefore, kidney transplant candidates may benefit from bariatric surgery, particularly sleeve gastrectomy (SG), as the safest, most effective, and long-lasting weight loss option to improve comorbidities and access to transplantation. However, concerns regarding nutritional risks prevent broader dissemination of SG in this population. No specific guidelines tailored to the nutritional needs of patients with renal disease undergoing SG have been developed. Moreover, appropriate monitoring strategies and interventions for muscle loss and functional status preservation, a major concern in this at-risk population, are unknown. We aimed to summarize the available literature on the nutritional requirements of patients with renal disease seeking SG as a bridge to transplantation. We also provide insight and guidance into the nutritional management pre and post-SG.

The impact of bariatric surgery on liver enzymes in people with obesity: A 5-year observational study.

BACKGROUND AND PURPOSE: Non-alcoholic fatty liver disease (NAFLD) has increasing worldwide prevalence, fuelled by rising obesity rates, and weight reduction is the mainstay of its management. We sought to study the effect of bariatric surgery, the most effective long-term treatment for obesity and associated metabolic disorders, on liver function in people with obesity. METHODS: We performed a retrospective longitudinal cohort study of 511 patients who had undergone bariatric surgery (71 sleeve gastrectomy and 440 gastric bypass) over 60 months of follow-up. Patients were stratified into groups based on their baseline alanine aminotransferase (ALT) into Group A (ALT < 40 U/L) and Group B (ALT > 40 U/L). Postoperative follow-up weight loss, liver function tests, HbA1c, blood pressure and lipid profiles were collected. FINDINGS: Bariatric surgery resulted in nadir total weight loss of 33.1% by 24 months (p < 0.001) with no significant difference between groups. In people with raised baseline ALT (Group B), ALT and gamma glutamyl transferase (GGT) levels decreased significantly by 4 months postoperatively (p < 0.001) and sustained over 60 months of follow-up. There was also significant and sustained reduction in HbA1c, blood pressure, total cholesterol, and non-HDL cholesterol overall with no differences between groups. CONCLUSIONS: Bariatric surgery results in significant weight loss, improves liver function tests and metabolic outcomes in people with obesity. Bariatric surgery could be a therapeutic consideration for patients with NAFLD associated with severe obesity who have otherwise been unresponsive to conservative management.

Metabolite signature of diabetes remission in individuals with obesity undergoing weight loss interventions.

OBJECTIVE: This observational study investigated metabolomic changes in individuals with type 2 diabetes (T2D) after weight loss. We hypothesized that metabolite changes associated with T2D-relevant phenotypes are signatures of improved health. METHODS: Fasting plasma samples from individuals undergoing bariatric surgery (n = 71 Roux-en-Y gastric bypass [RYGB], n = 22 gastric banding), lifestyle intervention (n = 66), or usual care (n = 14) were profiled for 139 metabolites before and 2 years after weight loss. Principal component analysis grouped correlated metabolites into factors. Association of preintervention metabolites was tested with preintervention clinical features and changes in T2D markers. Association between change in metabolites/metabolite factors and change in T2D remission markers, homeostasis model assessment of ß-cell function, homeostasis model assessment of insulin resistance, and glycated hemoglobin (HbA1c) was assessed. RESULTS: Branched-chain amino acids (BCAAs) were associated with preintervention adiposity. Changes in BCAAs (valine, leucine/isoleucine) and branched-chain ketoacids were positively associated with change in HbA1c (false discovery rate q value ≤ 0.001) that persisted after adjustment for percentage weight change and RYGB (p ≤ 0.02). In analyses stratified by RYGB or other weight loss method, some metabolites showed association with non-RYGB weight loss. CONCLUSIONS: This study confirmed known metabolite associations with obesity/T2D and showed an association of BCAAs with HbA1c change after weight loss, independent of the method or magnitude of weight loss.

The Evaluation of Gastric Emptying Using Nuclear Scintigraphy Compared to Three-Dimensional Multi-detector Computed Tomography (3D-MDCT) Gastric Volumetry in the Assessment of Poor Weight Loss Following Sleeve Gastrectomy.

BACKGROUND: Poor weight loss and weight regain are principal challenges following laparoscopic sleeve gastrectomy (LSG). There is a lack of standardised assessments and diagnostic tests to stratify the status post-LSG and determine whether anatomical or physiological problem exists. We aimed to compare nuclear scintigraphy gastric emptying with CT volumetric analysis of sleeve anatomy and determine the impact of anatomy on physiological function and its correlation with weight loss. MATERIALS AND METHODS: Patients greater than 12 months post-LSG were categorised into optimal weight loss (OWL) (n = 29) and poor weight loss groups (PWL) (n = 50). All patients underwent a protocolised nuclear scintigraphy and three-dimensional multi-detector computed tomography (3D-MDCT) gastric volumetry imaging. RESULTS: Post-operative % total weight loss in OWL was 26.2 ± 10.5% vs. 14.2 ± 10.7% in the PWL group (p value < 0.0001). The PWL group had significantly more delayed gastric emptying half-time than OWL (34.1 ± 18.8 vs. 19.5 ± 4.7, p value < 0.0001). Gastric emptying half-time showed statistically significant correlations with weight loss parameters (BMI; r = 0.215, p value 0.048, %EWL; r = - 0.336, p value 0.002 and %TWL; r = - 0.379, p value < 0.001). The median gastric volume on 3D-MDCT did not differ between the OWL (246 (IQR 50) ml) and PWL group (262 (IQR 129.5) ml), p value 0.515. Nuclear scintigraphy gastric emptying half-time was the most highly discriminant measure. A threshold of 21.2 min distinguished OWL from PWL patients with 86.4% sensitivity and 68.4% specificity. CONCLUSION: Nuclear scintigraphy is a potentially highly accurate tool in the functional assessment of sleeve gastrectomy physiology. It appears to perform better as a diagnostic test than volumetric assessment. Gastric volume did not correlate with weight loss outcomes. We have established diagnostic criteria of greater than 21 min to assess sleeve failure, which is linked to suboptimal weight loss outcomes.