Bariatric Surgery for Obesity

Overseen By Sarah Borden, MS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Columbia University

Must not be taking: Diabetes meds, Beta-blockers

Disqualifiers: Tobacco, Alcohol, Drug abuse, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

48 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore why weight-loss surgeries like Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) effectively treat obesity. Researchers measure changes in brain activity by analyzing certain chemicals in the cerebrospinal fluid before and after surgery, as well as after a very low-calorie diet (VLCD). The goal is to determine if surgery causes unique brain changes that aid long-term weight loss, potentially leading to new nonsurgical treatments. Individuals with a BMI between 35 and 55 who have not experienced significant weight changes in the past six months may be suitable candidates. As an unphased trial, this study offers participants the chance to contribute to groundbreaking research that could revolutionize obesity treatment.

Will I have to stop taking my current medications?

Yes, you will need to stop taking medications that affect body weight or blood sugar, as well as diabetes medications, beta-blockers, opiates, or glucocorticoids.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that weight-loss surgeries like Roux-en-Y Gastric Bypass and Sleeve Gastrectomy are generally safe for treating obesity. Studies indicate that Roux-en-Y Gastric Bypass can lead to significant weight loss and improvements in obesity-related health issues. However, risks include vitamin and mineral deficiencies and the possibility of needing additional surgeries later.

Sleeve Gastrectomy tends to have fewer long-term complications than Roux-en-Y, but there might be a higher chance of needing further surgery in the future. Both surgeries have a strong record of aiding weight loss and improving health over time.

The Very Low Calorie Diet (VLCD) is usually safe when supervised by a doctor. Research has shown that VLCDs can result in significant weight loss, but they may also cause side effects like gallstones and headaches. Medical supervision is important to reduce these risks.

In summary, all these treatments have proven effective and generally well-tolerated under medical care. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about these treatments for obesity because they offer diverse approaches to weight loss. Roux-en-Y Gastric Bypass (RYGB) is unique as it not only reduces stomach size but also changes the way the gut absorbs nutrients, potentially leading to significant long-term weight loss. Sleeve Gastrectomy (SG), on the other hand, involves removing a portion of the stomach, which limits food intake and impacts hunger hormones, making it different from RYGB. The Very Low Calorie Diet (VLCD) offers a non-surgical option, providing rapid weight loss through a strict dietary regimen that significantly cuts calorie intake. Each of these options provides a distinct pathway to tackle obesity, giving patients and doctors more tailored choices.

What evidence suggests that this trial's treatments could be effective for obesity?

This trial will compare Roux-en-Y Gastric Bypass (RYGB) surgery, Sleeve Gastrectomy (SG) surgery, and a Very Low Calorie Diet (VLCD) for obesity. Research has shown that RYGB surgery results in significant long-term weight loss, with patients maintaining an average of 23% weight loss even 20 years after surgery. Additionally, about 72% of patients maintained at least 20% of their weight loss after 10 years. SG surgery also leads to meaningful weight loss, with patients losing about 22.5% of their original weight over 5 years. VLCDs can cause quick weight loss initially, but long-term results often mirror more gradual diet plans. Overall, RYGB and SG are effective for lasting weight loss, while VLCDs offer short-term benefits. ^{6 7 8 9 10}

Who Is on the Research Team?

Sharon L Wardlaw, MD

Principal Investigator

Columbia University

Are You a Good Fit for This Trial?

This trial is for adults aged 18-65 with obesity, having a BMI between 35 and 55. Participants should not be on diabetes medications, beta-blockers, opiates or glucocorticoids; should have stable weight in the past six months; and must not use tobacco or abuse substances. Pregnant or breastfeeding individuals can't join the diet group.

Exclusion Criteria

No lactose intolerance

No recent weight change (+/-5%) within prior 6 months

No pregnancy, breastfeeding, or planning to become pregnant during the study (diet group only)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Pre-Intervention

Participants are assessed before the intervention, including lumbar puncture for CSF sampling and blood collection

1 week

1 visit (in-person)

Post-Surgery/Diet Weight Loss

Participants are assessed after achieving 10-15% weight loss, including lumbar puncture for CSF sampling and blood collection

12 weeks for diet participants, variable for surgery participants

1 visit (in-person)

12-Month Follow-up

Participants are assessed 12 months after surgery, including lumbar puncture for CSF sampling and blood collection

12 months

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Roux-en-Y Gastric Bypass (RYGB)
• Sleeve Gastrectomy (SG)
• Very Low Calorie Diet (VLCD)

Trial Overview The study compares brain changes in obese patients undergoing Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy (SG) to those following a Very Low Calorie Diet (VLCD). It measures cerebrospinal fluid to track appetite-regulating hormones before and after these interventions.

How Is the Trial Designed?

Group I: Roux-en-Y Gastric Bypass Surgery Active Control 1 Intervention

Group II: Sleeve Gastrectomy Surgery Active Control 1 Intervention

Group III: Very Low Calorie Diet Active Control 1 Intervention

Roux-en-Y Gastric Bypass (RYGB) is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Roux-en-Y Gastric Bypass for:

• Obesity
• Type 2 Diabetes
• Gastroesophageal Reflux Disease (GERD)
• Sleep Apnea

Approved in European Union as Roux-en-Y Gastric Bypass for:

• Obesity
• Type 2 Diabetes
• Hypertension
• Hyperlipidemia

Approved in Canada as Roux-en-Y Gastric Bypass for:

• Obesity
• Type 2 Diabetes
• Gastroesophageal Reflux Disease (GERD)
• Sleep Apnea

Who Is Running the Clinical Trial?

Columbia University

Lead Sponsor

Trials

1,529

Recruited

2,832,000+

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Collaborator

Trials

2,513

Recruited

4,366,000+

Published Research Related to This Trial

Vitamin D deficiency (VDD) is highly prevalent in bariatric surgery patients, with preoperative rates ranging from 13% to 90%, and postoperative rates remaining similarly high, especially after Roux-en-Y gastric bypass (RYGB).

Current vitamin D supplementation regimens post-surgery, often below 800 IU daily, are generally insufficient to raise serum 25(OH)D levels above the optimal threshold of 30 ng/mL, indicating a critical need for more effective and personalized supplementation strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Vitamin D status and supplementation before and after bariatric surgery: a comprehensive literature review. Peterson, LA., Zeng, X., Caufield-Noll, CP., et al.[2018]

Secondary Roux-en-Y gastric bypass (RYGB) after adjustable gastric banding (AGB) or vertical banded gastroplasty (VBG) resulted in significantly lower long-term weight loss compared to primary RYGB, with %Total Weight Loss (%TWL) of 7.56% versus 24.51% and %Excess Weight Loss (%EWL) of 17.15% versus 55.61%.

While secondary RYGB had a similar rate of obesity-related comorbidity improvement and quality of life scores compared to primary RYGB, it was associated with a higher incidence of gastroesophageal reflux disease (GERD) at 43.75% compared to 25% in primary RYGB.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Primary Roux-en-Y Gastric Bypass Results in Greater Weight Loss at 15-Year Follow-Up Compared with Secondary Roux-en-Y Gastric Bypass After Failure of Gastric Band or Mason McLean Vertical Gastroplasty. Etienne, JH., Petrucciani, N., Goetschy, M., et al.[2021]

Converting from open vertical banded gastroplasty (VBG) to Roux-en-Y gastric bypass (RYGB) is a feasible and safe procedure, with an acceptable complication rate of 8.9% and high patient satisfaction (86.4% would repeat the conversion).

Patients experienced significant weight loss after conversion, achieving an average excess weight loss of 78.0% after one year, which remained substantial over six years, demonstrating the long-term efficacy of the procedure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Conversion of Open Vertical Banded Gastroplasty to Roux-en-Y Gastric Bypass: a Single-Center, Single-Surgeon Experience with 6 Years of Follow-up. Gys, B., Haenen, F., Ruyssers, M., et al.[2018]

In a study of 178 patients who underwent conversion to Roux-en-Y gastric bypass (RYGB) after either adjustable gastric banding (AGB) or sleeve gastrectomy (SG), the rates of postoperative complications were similar between the two groups, indicating a comparable safety profile.

Both groups experienced similar total body weight loss after 2 years, with no significant difference, suggesting that conversion from either AGB or SG to RYGB can be effective for addressing weight regain or insufficient weight loss.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Conversion to Gastric Bypass After Either Failed Gastric Band or Failed Sleeve Gastrectomy. van Wezenbeek, MR., van Oudheusden, TR., de Zoete, JP., et al.[2018]

Roux-en-Y gastric bypass (RYGB) was found to be more effective than sleeve gastrectomy (SG) in resolving obesity-related health issues like type 2 diabetes, hypertension, and hypercholesterolemia, based on a meta-analysis of 32 studies involving 6526 patients.

Despite its effectiveness, RYGB was associated with a higher rate of complications and reoperations, as well as longer surgery times, making SG a safer option overall.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of the long-term results of Roux-en-Y gastric bypass and sleeve gastrectomy for morbid obesity: a systematic review and meta-analysis of randomized and nonrandomized trials. Li, JF., Lai, DD., Lin, ZH., et al.[2018]

In a study of 772 patients undergoing vertical sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB), several independent predictors of severe complications were identified, including male gender, open and revisional surgery, hypertension, and hypoalbuminemia.

Hypoalbuminemia was particularly linked to deep surgical site infections and leaks, while open surgery was associated with both superficial and deep infections as well as respiratory complications, highlighting the importance of recognizing these risk factors to improve surgical outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Risk factors for early postoperative complications after bariatric surgery. Husain, F., Jeong, IH., Spight, D., et al.[2022]

Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy lead to significant hormonal changes that enhance weight loss and improve diabetes management by increasing the secretion of appetite-regulating hormones like GLP-1 and peptide YY.

These surgeries improve glucose metabolism through mechanisms such as increased insulin sensitivity and better beta-cell function, highlighting their effectiveness in promoting long-term weight loss and glycemic control.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Updates in weight loss surgery and gastrointestinal peptides. Svane, MS., Bojsen-Møller, KN., Madsbad, S., et al.[2018]

In a study of 213 type 2 diabetes patients with a BMI of 25 to 32.5 kg/m2, Roux-en-Y gastric bypass (RYGB) was found to be more effective than medical treatment in achieving significant metabolic improvements, with 23.9% of RYGB patients meeting the triple endpoint compared to only 7.0% in the medical group.

However, RYGB was associated with a higher rate of complications (36 vs. 22), highlighting the need to weigh the benefits of improved metabolic outcomes against the risks of surgical complications when considering treatment options for patients with lower BMI.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Two-year outcomes of Roux-en-Y gastric bypass vs medical treatment in type 2 diabetes with a body mass index lower than 32.5 kg/m2: a multicenter propensity score-matched analysis. Ling, J., Tang, H., Meng, H., et al.[2022]

Roux-en-Y gastric bypass (RYGB) surgery led to significant weight loss (average -21.6%) and improvements in cardiovascular risk factors among 30 participants, including those with and without type 2 diabetes.

However, the surgery also resulted in increased levels of inflammatory markers in fecal samples, suggesting a potential risk for gastrointestinal inflammation and possibly linking RYGB to higher risks of inflammatory bowel disease and colorectal cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gastrointestinal manifestations after Roux-en-Y gastric bypass surgery in individuals with and without type 2 diabetes. Härma, MA., Adeshara, K., Istomin, N., et al.[2021]

Roux-en-Y gastric bypass (RYGB) is a safe and effective bariatric surgery for achieving long-term weight loss in obese Chinese patients with a BMI under 35 kg/m2, with 37% of patients maintaining significant weight loss after 5 years.

Early weight loss, specifically a total body weight loss of 24.39% at 6 months, is a strong predictor of successful weight maintenance at 5 years, indicating that monitoring early outcomes can help assess long-term success.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Weight loss at six months is the surrogate of long-term treatment outcomes for obese Chinese with a BMI less than 35 kg/m2 undergoing Roux-en-Y gastric bypass. Du, D., Wang, L., Chen, W., et al.[2022]

In a study of 54 patients who converted from vertical banded gastroplasty (VBG) to Roux-en-Y gastric bypass (RYGB), the procedure was found to be safe with no perioperative deaths and a low complication rate (13%).

After an average follow-up of 6.1 years, patients experienced significant weight loss, with mean BMI decreasing from 46 kg/m² to 35 kg/m², and 90% reported satisfaction with the results, along with improvements in weight-related health issues.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Unsatisfactory weight loss after vertical banded gastroplasty: is conversion to Roux-en-Y gastric bypass successful? Cordera, F., Mai, JL., Thompson, GB., et al.[2004]

In a study of 422 patients undergoing either Roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG), those who had RYGB experienced greater weight loss at both 1 and 2 years post-surgery compared to those who had VSG, with median percentage weight changes of -31.5% and -31.2% for RYGB versus -25.3% and -23.3% for VSG, respectively.

Younger patients tended to lose more weight than older patients after surgery, but psychological factors such as depression and anxiety did not significantly influence weight loss outcomes for either surgical method.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Guiding Patients Toward the Appropriate Surgical Treatment for Obesity: Should Presurgery Psychological Correlates Influence Choice Between Roux-en-Y Gastric Bypass and Vertical Sleeve Gastrectomy? Ames, GE., Heckman, MG., Diehl, NN., et al.[2018]

In a study of 313 morbidly obese patients who underwent Roux-en-Y gastric bypass (RYGB), the length of the biliopancreatic limb (BPL) and alimentary limb (AL) did not significantly affect %excess weight loss (%EWL) after 12 months.

However, after 36 months, patients with a longer BPL experienced a significantly higher %EWL compared to those with a shorter BPL, suggesting that BPL length may play a role in long-term weight loss outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The role of alimentary and biliopancreatic limb length in outcomes of Roux-en-Y gastric bypass. Darabi, S., Pazouki, A., Hosseini-Baharanchi, FS., et al.[2022]

In a study of 678 patients with a history of solid organ transplantation, Roux-en-Y Gastric Bypass (RYGB) was found to be associated with significantly higher overall morbidity and surgical complications compared to Sleeve Gastrectomy (SG).

After adjusting for patient characteristics, RYGB showed a trend towards increased readmissions related to surgery, indicating that SG may be a safer option for this patient population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Is Bariatric Procedure Type Associated With Morbidity in Transplant Patients? Fagenson, AM., Mazzei, M., Swaszek, L., et al.[2022]

Citations

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Evaluating the Effectiveness and Long-term Outcomes of ... Results: RYGB was associated with more significant long-term weight loss and superior T2DM remission rates. SG had a lower risk of nutritional ...

2. asmbs.org asmbs.org/news_releases/new-study-shows-long-term-effectiveness-of-gastric-bypass-in-treating-type-2-diabetes-and-obesity/

New Study Shows Long-term Effectiveness of Gastric ... Peak weight loss of 31.8% was achieved after 18 months and stabilized at 23% after 10 years and up to the 20-year mark. The overall 15-year ...

3. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/26720434/

10-Year Outcomes After Roux-en-Y Gastric Bypass Annual % reduction in excess body mass index significantly improved over time, peaking at 74% by 24 months, with a slow trend down to 52% at 10 years (all P < ...

4. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2819400

Ten-Year Outcomes Following Roux-en-Y Gastric Bypass ... At 10 years, 70% of patients with RYGB still had a BMI of 40 or greater. The DS procedure conferred some benefits related to lipid and glycemic ...

5. nejm.org nejm.org/doi/full/10.1056/NEJMoa1700459

Weight and Metabolic Outcomes 12 Years after Gastric ... Furthermore, at 10 years, 72% of the patients who had undergone Roux-en-Y gastric bypass had maintained at least a 20% weight loss from baseline ...

6. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/37140720/

a Systematic Review of Bariatric and Metabolic Surgery The rationale of this systematic review is to compare the safety and efficacy between Roux-en-Y gastric bypass (RYGB), one anastomosis gastric ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC1421184/

Outcomes After Laparoscopic Roux-en-Y Gastric Bypass for ... Roux-en-Y gastric bypass (RYGBP) has been shown to produce significant weight loss in patients with clinically severe obesity: most studies report a weight loss ...

8. sciencedirect.com sciencedirect.com/science/article/abs/pii/S0039606024001818

Comprehensive outcomes after Roux-en-Y gastric bypass ... The maximum mean percentage total weight loss achieved at 1 year was 31.5% ± 5.7% and was consistently >20% throughout follow-up. Sustained resolution of ...

9. jamanetwork.com jamanetwork.com/journals/jamasurgery/article-abstract/2830466

Long-Term Outcomes of Laparoscopic Roux-en-Y Gastric ... The SM-BOSS randomized clinical trial found no significant difference in weight loss between SG and RYGB in the intention-to-treat analysis.

10. thelancet.com thelancet.com/journals/landia/article/PIIS2213-8587(25)00025-7/fulltext

Roux-en-Y gastric bypass, adjustable gastric banding, or ... Metabolic and bariatric surgery can lead to 20–30% total weight loss. Trials show that obesity management medications can lead to reductions of ...