Ghrelin, glucagon-like peptide-1, and peptide YY secretion in patients with and without weight regain during long-term follow-up after bariatric surgery: a cross-sectional study

Endocrine and metabolic effects of GLP-1 receptor agonists on women with PCOS, a narrative review

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. This condition is associated with various hormonal, reproductive and metabolic alterations, including androgen excess, ovulatory disorders and a hyperinsulinemic state. A personalized therapeutic approach is necessary to improve PCOS, focusing on patients' main concerns, with the goal of addressing ovarian dysfunction, reducing hyperandrogenism and improving metabolic alterations, particularly through weight reduction. The therapeutic class of glucagon-like peptide-1 receptor analogues (GLP-1 RAs) represents an attractive option for PCOS due to its various beneficial effects, such as weight loss. In this review, we discuss the clinical and pathological aspects of PCOS, as well as the data and potential roles of GLP-1 RAs in managing this condition.

The role of relative fat mass in gallstone risk assessment: findings from the NHANES 2017-2020 survey

Background

Gallstones are a prevalent condition that can lead to significant morbidity and healthcare costs. Relative fat mass (RFM), as a potential marker of body fat distribution, may offer insights beyond traditional metrics like body mass index (BMI) and waist circumference. This study aims to investigate the association between RFM and gallstone prevalence in the U.S. population.

Methods

The study cohort comprised 6,881 participants obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 2017 and 2020. Participants were stratified into quartiles (Q1-Q4) based on their RFM. To evaluate the associations, multivariable logistic regression analyses were employed to assess odds ratios (OR) for gallstone risk across different quartiles of RFM. Additionally, restricted cubic spline analysis was conducted to ascertain the relationship trend while subgroup analyses examined interactions based on age, sex, race, education level, and lifestyle factors.

Results

The analysis revealed significant associations for participants within the higher RFM quartiles (Q3 and Q4), with ORs of 2.58 (95% CI: 1.65, 4.04) and 6.30 (95% CI: 3.63, 10.93), respectively, compared to Q1. The findings consistently indicated that RFM, particularly in Q4, is a strong predictor of gallstone risk, demonstrating superior predictive performance relative to waist circumference and BMI, as evidenced by an AUC of 0.702.

Conclusion

Elevated RFM is a noteworthy predictor of gallstone risk in the studied population, suggesting its potential utility in clinical risk assessment frameworks. Future research should focus on elucidating the underlying mechanisms driving this association and exploring RFM's applicability as a pragmatic tool in clinical practice for gallstone risk stratification.

Glucagon-Like Peptide-1 Receptor Agonists for the Treatment of Suboptimal Initial Clinical Response and Weight Gain Recurrence After Bariatric Surgery: a Systematic Review and Meta-analysis

BACKGROUND

Suboptimal initial clinical response (SICR) and weight gain recurrence (WGR) are challenging issues following bariatric surgery. Recently, the promising weight loss effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have been applied to bariatric patients. We aimed to conduct a systematic review and meta-analysis to evaluate the efficacy and safety of GLP-1 RAs in the treatment of SICR and WGR after bariatric surgery.

METHODS

A literature search was performed across online databases. The primary outcomes were percentage of total weight loss (%TWL) and absolute weight loss. Secondary outcomes included changes in biochemical markers and adverse effects (AEs).

RESULTS

Nineteen studies including 1290 patients were included. After at least 3 months of treatment, the pooled %TWL was 9.24% for liraglutide, 11.38% for semaglutide, and 15.50% for tirzepatide, with corresponding weight reductions of 8.56 kg, 11.62 kg, and 12.60 kg, respectively. Additionally, %TWL and weight loss with liraglutide use were 7.65% and 7.47 kg for ≤ 6 months, 10.22% and 9.30 kg for 6-12 months, and 10.80% and 9.72 kg for ≥ 12 months. For semaglutide, the %TWL and weight reduction were 10.18% and 9.43 kg at 6 months, and 13.15% and 14.68 kg at 12 months. Biochemical markers including triglycerides, total cholesterol, low-density lipoprotein cholesterol, glycated hemoglobin, and alanine aminotransferase levels showed significant reductions after GLP-1 RA treatment. Common AEs were nausea (23%), vomiting (6%), diarrhea (6%), constipation (10%), headache (6%), fatigue (8%), abdominal pain (2%), and abdominal bloating (2%). The proportion of patients who discontinued the treatment due to AEs was 3%.

CONCLUSIONS

GLP-1 RAs are effective and safe for treating SICR and WGR after bariatric surgery.

Post metabolic bariatric surgery weight regain: the importance of GLP-1 levels

Weight regain and insufficient weight loss are essential problems after metabolic bariatric surgery (MBS) in people living with obesity. Changes in the level of glucagon-like peptide-1 (GLP-1) secreted from the gut after bariatric surgery are one of the underlying mechanisms for successful initial weight loss. Studies and meta-analyses have revealed that postprandial GLP-1 levels increase after the Roux-en-Y gastric bypass and sleeve gastrectomy, but fasting GLP-1 levels do not increase significantly. Some observational studies have shown the relationship between higher postprandial GLP-1 levels and successful weight loss after bariatric surgery. There is growing evidence that GLP-1-receptor agonist (GLP-1-RA) use in patients who regained weight after bariatric surgery has resulted in significant weight loss. In this review, we aimed to summarize the changes in endogenous GLP-1 levels and their association with weight loss after MBS, describe the effects of GLP-1-RA use on weight loss after MBS, and emphasize metabolic adaptations in light of the recent literature. We hypothesized that maintaining higher basal-bolus GLP-1-RA levels may be a promising treatment choice in people with obesity who failed to lose weight after bariatric surgery.

Critical Time Points for Assessing Long-Term Clinical Response After Sleeve Gastrectomy-A Retrospective Study of Patients with 13-Year Follow-Up

BACKGROUND

Weight loss after sleeve gastrectomy (SG) demonstrates significant diversity in the long term and the implicated mechanisms behind suboptimal clinical response (SCR) or recurrent weight gain (RWG) need to be scrutinized. This study retrospectively examines weight-loss trajectories, aiming to identify critical time points to optimize follow-up strategies and guide future prospective research.

METHODS

This is a single-center, retrospective study of 104 patients that underwent SG. Excess body weight loss (%EWL) was calculated at 1, 3, 6, 12, 24, 60, and at 160.4 ± 16 months, while RWG was defined as the difference between the body mass index (BMI) at evaluation and the minimum BMI achieved postoperatively. In accordance with the clinical response, patients were classified into good responders (Group A: %EWL ≥ 50 and RWG < 5 kg/m2), partial responders (Group B: %EWL ≥ 50 and RWG ≥ 5 kg/m2) and weak responders (Group C: %EWL < 50).

RESULTS

In the first postoperative month good responders achieved the highest %EWL 24.4 ± 6.5, compared to the other two groups (p < 0.05). After 24 months, all patients showed a decrease in %EWL, with good and partial responders following the same pattern until the fifth year. After the fifth year, EWL% was significantly decreased in partial responders (p = 0.014), while in good responders it remained relatively unchanged (p = 0.159).

CONCLUSION

The first postoperative month and the fifth postoperative year have been identified as potential critical periods for determining long-term clinical outcomes.

Awareness of Metabolic Bariatric Surgery Among Medical Students and House Officers in Lagos, Nigeria: A Cross-Sectional Online Survey

Background Obesity poses a significant public health challenge globally as it is a risk factor for many non-communicable diseases (NCDs). Metabolic bariatric surgery (MBS) has proven to be a reliable method for ensuring sustained weight loss and sometimes resolution of obesity-related diseases. However, its uptake and utilization in Nigeria are low due to a variety of reasons, one of which may be insufficient knowledge and exposure to surgical methods of weight loss in medical school curricula. This study evaluated knowledge and attitudes regarding MBS among final-year medical students and house officers (HOs) in Lagos, Nigeria, who represent primary sources of health information for patients. Methods A cross-sectional study was conducted using a 19-point structured online questionnaire, which was divided into the following sections: demographics, knowledge assessment, and attitude measurement. This was distributed electronically using a convenience sampling technique to final-year medical students and HOs across Lagos teaching hospitals (April-July 2024). Ethical approval was not required for this study. Data analysis was performed using SPSS v27.0.1 (IBM Corp., Armonk, NY). Results A total of 203 responses were received. Of these, 117 respondents were female (57.6%), and 86 were male (42.4%). Final-year medical students accounted for 130 (64%), while HOs made up the remaining 73 (36%). Only eight respondents (3.9%) correctly identified all three primary indications for MBS. The failure of conservative methods of weight loss was the most correctly identified indication for MBS, selected by 66% of participants (n=134). Recognition of gastric bypass and sleeve gastrectomy was moderate, with 66.5% (n=135) and 63.5% (n=129) of respondents aware of these methods, respectively. However, only 29.6% (n=60) of respondents were aware of endoscopic balloon insertion. Notably, 94.6% (n=192) were unaware of bariatric services at their institutions, and 41.9% (n=85) reported no exposure to bariatric surgery in their medical school curriculum. There was significant uncertainty regarding surgical risk, with 47.3% (n=96) unable to compare MBS risks to common abdominal procedures. Additionally, 47.3% (96) anticipated social stigma associated with surgical weight loss interventions. Conclusion Nigeria is confronting a growing obesity epidemic that underscores the urgent need for a comprehensive national strategy. Central to this approach is the enhancement of medical education on obesity and MBS through targeted curriculum updates, ongoing professional development programs, and specialized training workshops. Such measures are essential to improving patient care and addressing the escalating burden of obesity in Nigeria.

Outcomes and complications after long versus short gastric pouch Roux-en-Y gastric bypass in patients with severe obesity

Roux-en-Y gastric bypass (RYGB) is the second most common metabolic and bariatric surgery (MBS) globally. The impact of pouch size on weight loss outcomes and complications remains unclear. This study aims to compare the weight loss outcomes and complications in long pouch versus short pouch RYGB in patients with severe obesity. This retrospective study, conducted in 2021 in two academic tertiary Hospitals, included patients aged 18-65 with severe obesity who underwent RYGB with two different methods. Demographic data, past medical history, and surgical details were assessed. The study outcome was postoperative metrics at 12 months including weight loss outcomes and complications like marginal ulceration, and leaks. A total of 219 patients, who were included in this study, were divided into two groups: 107 with long gastric pouches and 112 with short gastric pouches. The average age was 41.33 ± 10.26 and 42.45 ± 11.70 in long and short gastric pouches, respectively. Patients with long gastric pouches had a mean weight of 113.29 ± 16.52 kg and mean Body Mass Index (BMI) of 42.97 ± 4.15 kg/m2, and patients with short gastric pouches had a mean weight of 118.39 ± 12.80 kg and mean BMI of 45.21 ± 5.10 kg/m2. At 12 months after surgery, substantial weight loss was noted in all participants (37.8 ± 10.7 kg in patients with long gastric pouch; 48.1 ± 11.3 kg in patients with short gastric pouch; P = 0.033). Delta BMI (P = 0.072), and TWL% (P = 0.061), were more pronounced in patients with short pouches, however the difference was not significant. Remission of underlying diseases and endoscopic findings were comparable for short and long gastric pouch groups. Both long and short-pouch gastric bypass surgeries are effective and safe for weight loss and remission of obesity-associated medical problems in patients with severe obesity and exhibited similar rates for remission of underlying diseases and endoscopic findings. More studies are needed to individualize surgical approaches based on patient characteristics.

Association between ideal cardiovascular health and bowel conditions among US adults

Objective

The aim of this study is to explore the relationship between ideal cardiovascular health (CVH), as assessed using the Life's Essential 8 (LE8), and bowel conditions.

Methods

This cross-sectional study selected 11,108 participants aged ≥20 years from 2005 to 2010 National Health and Nutrition Examination Survey. LE8 scores (range 0-100) were measured according to American Heart Association definitions and were divided into health behavior and health factor scores. Bowel conditions including chronic diarrhea, constipation, and fecal incontinence were diagnosed by the Bowel Health Questionnaire. Weighted logistic regression and restricted cubic spline models were used for correlation analysis.

Results

Logistic regression results showed that LE8 scores were negatively associated with chronic diarrhea and fecal incontinence, but the difference with chronic constipation was not statistically significant. The health behaviors subscale was also negatively correlated with chronic diarrhea, chronic constipation, and fecal incontinence, but health factors were negatively related to chronic diarrhea and fecal incontinence and positively related to chronic constipation. The RCS was consistent with the trend of the logistic regression findings. Sensitivity analyses reconfirmed these outcomes.

Conclusion

LE8 is highly associated with chronic diarrhea and fecal incontinence, not with chronic constipation. Encouraging optimization of CVH levels may be beneficial for bowel disorders, and prevention of bowel disorders may enhance CVH.

Efficacy of single anastomosis sleeve-ileal bypass in weight control and resolution of type 2 diabetes mellitus - a retrospective cohort study

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder exacerbated by obesity. Single Anastomosis Sleeve-Ileal Bypass (SASI) has emerged as a promising metabolic bariatric procedure that combines sleeve gastrectomy and ileal bypass, facilitating substantial weight loss and T2DM remission through restrictive and malabsorptive mechanisms. This study aims to evaluate the effects of SASI on T2DM remission, weight loss, and safety in one year follow-up. A retrospective cohort study analyzed 31 patients with obesity and T2DM who underwent SASI. Data collected included demographic characteristics, preoperative and postoperative BMI, HbA1c levels, and bariatric outcomes, including %TWL and T2DM changes. The mean age was 45 years, with a mean preoperative BMI of 40.7 kg/m². One year postoperatively, the mean %EWL was 85.6% and %TWL was 31.7%. T2DM remission was achieved in 24 (77.4%) patients, improvement in 4 (12.9%), and no change in 3 (9.7%). Hypertension improved in 21 (87.5%) patients, with 12 (50%) achieving remission. Significant reductions in BMI and HbA1c levels were observed (p < 0.001). Responders (R) and non-responders (NR) groups showed significant differences in postoperative BMI and %EWL (p = 0.007, p = 0.023). One patient experienced a Clavien-Dindo Grade III complication; no deaths occurred. SASI is an effective and safe procedure for treating T2DM, resulting in significant weight loss and metabolic improvements over a one-year follow-up. SASI seems to be a favorable option for T2DM management in metabolic bariatric surgery.

RNA sequencing unravels novel L cell constituents and mechanisms of GLP-1 secretion in human gastric bypass-operated intestine

AIMS/HYPOTHESIS

Roux-en-Y gastric bypass surgery (RYGB) frequently results in remission of type 2 diabetes as well as exaggerated secretion of glucagon-like peptide-1 (GLP-1). Here, we assessed RYGB-induced transcriptomic alterations in the small intestine and investigated how they were related to the regulation of GLP-1 production and secretion in vitro and in vivo.

METHODS

Human jejunal samples taken perisurgically and 1 year post RYGB (n=13) were analysed by RNA-seq. Guided by bioinformatics analysis we targeted four genes involved in cholesterol biosynthesis, which we confirmed to be expressed in human L cells, for potential involvement in GLP-1 regulation using siRNAs in GLUTag and STC-1 cells. Gene expression analyses, GLP-1 secretion measurements, intracellular calcium imaging and RNA-seq were performed in vitro. OGTTs were performed in C57BL/6j and iScd1-/- mice and immunohistochemistry and gene expression analyses were performed ex vivo.

RESULTS

Gene Ontology (GO) analysis identified cholesterol biosynthesis as being most affected by RYGB. Silencing or chemical inhibition of stearoyl-CoA desaturase 1 (SCD1), a key enzyme in the synthesis of monounsaturated fatty acids, was found to reduce Gcg expression and secretion of GLP-1 by GLUTag and STC-1 cells. Scd1 knockdown also reduced intracellular Ca2+ signalling and membrane depolarisation. Furthermore, Scd1 mRNA expression was found to be regulated by NEFAs but not glucose. RNA-seq of SCD1 inhibitor-treated GLUTag cells identified altered expression of genes implicated in ATP generation and glycolysis. Finally, gene expression and immunohistochemical analysis of the jejunum of the intestine-specific Scd1 knockout mouse model, iScd1-/-, revealed a twofold higher L cell density and a twofold increase in Gcg mRNA expression.

CONCLUSIONS/INTERPRETATION

RYGB caused robust alterations in the jejunal transcriptome, with genes involved in cholesterol biosynthesis being most affected. Our data highlight SCD as an RYGB-regulated L cell constituent that regulates the production and secretion of GLP-1.

Suboptimal Weight Loss 13 Years After Roux-en-Y Gastric Bypass Is Associated with Blunted Appetite Response

PURPOSE

Bariatric surgery remains the most efficient treatment to achieve a sustained weight loss. However, a large proportion of patients experience suboptimal weight loss (SWL). The exact mechanisms involved remain to be fully elucidated, but the homeostatic appetite control system seems to be involved. The aim of this study was, therefore, to compare the plasma concentration of gastrointestinal hormones, and appetite ratings, between those experiencing SWL and optimal weight loss (OWL) after Roux-en-Y gastric bypass (RYGB).

MATERIALS AND METHODS

Fifty participants from the Bariatric Surgery Observation Study (BAROBS) experiencing either SWL or OWL (< or ≥ 50% of excess weight loss (EWL), respectively) > 13 years post-RYGB were compared to 25 non-surgical controls. Plasma concentrations of acylated ghrelin (AG), total glucagon-like peptide-1 (GLP-1), total peptide YY (PYY), cholecystokinin (CCK), and subjective ratings of hunger, fullness, desire to eat (DTE), and prospective food consumption (PFC) were assessed in the fasting and postprandial (area under the curve (AUC)) states.

RESULTS

Those experiencing OWL presented with higher basal AG and GLP-1 iAUC, and lower AG iAUC compared with SWL and controls. Additionally, both bariatric groups presented with higher PYY and CCK iAUC compared to controls. PFC tAUC was also lower in OWL compared to the SWL group. Total weight loss was positively correlated with GLP-1 tAUC and negatively correlated with fasting and tAUC DTE and PFC tAUC.

CONCLUSIONS

SWL > 13 years post-RYGB is associated with lower basal ghrelin, as well as a weaker satiety response to a meal. Future studies should investigate the causality of these associations.

Diabetes Remission After LRYGBP With and Without Fundus Resection: a Randomized Clinical Trial

BACKGROUND

Glycemic control, after metabolic surgery, is achieved in two stages, initially with neuroendocrine alterations and in the long-term with sustainable weight loss. The resection of the gastric fundus, as the major site of ghrelin production, is probably related with optimized glucose regulation. The aim of the present study is to investigate whether the modification of laparoscopic Roux-en-Y gastric bypass (LRYGBP) with fundus resection offers superior glycemic control, compared to typical LRYGBP.

MATERIALS AND METHODS

Participants were 24 patients with body mass index (BMI) ≥40kg/m2 and type II diabetes mellitus (T2DM), who were randomly assigned to undergo LRYGBP and LRYGBP with fundus resection (LRYGBP+FR). Gastrointestinal (GI) hormones [ghrelin, glucagon-like-peptide-1 (GLP-1), peptide-YY (PYY)] and glycemic parameters (glucose, insulin, HbA1c, C-peptide, insulinogenic index, HOMA-IR) were measured preoperatively, at 6 and 12 months during an oral glucose tolerance test (OGTT).

RESULTS

Ninety-five percent of patients showed complete remission of T2DM after 12 months. LRYGBP+FR was not related with improved glycemic control, compared to LRYGBP. Ghrelin levels were not significantly reduced at 6 and 12 months after LRYGBP+FR. GLP-1 and PYY levels were remarkably increased postprandially in both groups at 6 and 12 months postoperatively (p<0.01). Patients who underwent LRYGBP+FR achieved a significantly lower BMI at 12 months in comparison to LRYGBP (p<0.05).

CONCLUSION

Fundus resection is not associated with improved glycemic regulation, compared to typical LRYGBP and the significant decrease in BMI after LRYGBP+FR has to be further confirmed with longer follow-up.

Significance of Hormone Alteration Following Bariatric Surgery

The prevalence of obesity has increased significantly over the last several decades, and with its increase comes a wide variety of comorbidities, such as diabetes and cardiovascular disease. Traditionally, diet and exercise have been prescribed for individuals to try and regain control of their weight and health status. Despite this successful method, the compliance rate is significantly below the desired amount. Over the last few decades, a new treatment has been offered to significantly decrease an individual's weight to an optimal BMI between 18 and 25 kg/m2. Bariatric surgery has been proposed to be the most appropriate treatment for obesity, and there are several different types of bariatric surgery: Roux-en-Y gastric bypass (RYGB), biliopancreatic diversion with duodenal switch (BPD-DS), adjustable gastric band (AGB), and sleeve gastrectomy (SG). Hormones may be significantly involved in losing and maintaining weight loss. This paper aims to evaluate hormone changes in appetite suppression, appetite activation, glycemic control, and lipid metabolism and how these impact overall weight loss concerning the most prominent surgeries. The hormones assessed were ghrelin, insulin, leptin, GLP-1, PYY, and adiponectin, and their levels before and after each surgery were compared. RYGB is one of the most successful types of bariatric surgeries, and this correlates with it having the most suppressed levels of ghrelin, insulin, and leptin following surgery with a slow return to normal. RYGB has also led to the most significant increased levels of PYY, pre- and post-prandial GLP-1, and adiponectin. Hormones following SG followed the hormone trend after RYGB but were not as prominent. BDP-DS has the highest success rate. However, numerous adverse effects have limited the amount of studies assessing the surgery. What was present was not as significant as RYGB, possibly due to manipulation.

Prevalence of hyperuricemia among type 2 diabetes mellitus patients in Africa: a systematic review and meta-analysis

BACKGROUND

Hyperuricemia increases morbidity and mortality in type 2 diabetic individuals. It is linked to the expansion of diabetes and cardiovascular diseases indicators, as well as being a significant predictor of coronary artery disease. It also leads to a poor prognosis and increment of diabetic complications including diabetic neuropathy, retinopathy, and nephropathy. Therefore, this systematic review and meta-analysis was aimed to determine the pooled prevalence of hyperuricemia among type 2 diabetes mellitus patients in Africa.

METHODS

We conducted a systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. To identify relevant articles, we searched electronic databases such as PubMed, Google Scholar, African Journal Online, Science Direct, Embase, ResearchGate, Scopus, and Web of Sciences. The quality of the included studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. Statistical analysis was performed using Stata 14.0 software. To evaluate heterogeneity, we utilized Cochran's Q test and I² statistics. Publication bias was assessed through the examination of a funnel plot and Egger's test. The pooled prevalence was estimated using a random effect model. Furthermore, sub-group and sensitivity analyses were conducted.

RESULTS

The overall pooled prevalence of hyperuricemia among type 2 diabetic patients in Africa was 27.28% (95% CI: 23.07, 31.49). The prevalence was highest in Central Africa 33.72% (95% CI: 23.49, 43.95), and lowest in North Africa 24.72% (95% CI: 14.38, 35.07). Regarding sex, the pooled prevalence of hyperuricemia among female and male type 2 diabetic patients was 28.02% (95% CI: 22.92, 33.48) and 28.20% (95% CI: 22.92, 33.48), respectively.

CONCLUSION

This systematic review and meta-analysis showed a high prevalence of hyperuricemia among type 2 diabetic patients. So, regular screening and diagnosis of hyperuricemia required for preventing its pathological effects and contribution to chronic complications of diabetes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (2022: CRD42022331279).

Definition, Mechanisms and Predictors of Weight Loss Failure After Bariatric Surgery

It has been proven that surgery is more effective than non-surgical treatment in obese patients. However, this approach has several disadvantages, especially long-term weight loss. Weight loss failures can be broadly classified into two categories; insufficient weight loss (poor responder) and weight regain. However, a unified definition has not been established yet for each category, and there is no clear standard for the post-surgery time point to be used to assess weight loss failure. In addition, analyzing factors that contribute to weight loss failure will lead to strategies for reducing it. Therefore, many researchers have been interested in this subject and have published conflicting results. This review presents a definition for and describes the mechanisms and predictors of weight loss failure after bariatric surgery.