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

Trial Summary

What is the purpose of this trial?

The goal of this project is to understand why bariatric surgery is such an effective treatment for obesity with a focus on brain mechanisms. Cerebrospinal fluid (CSF) neuropeptide, hormone and protein levels will be measured as a surrogate for changes in brain activity in participants before and after bariatric surgery as compared with participants before and after diet-induced weight loss. The investigators are studying neuropeptides and hormones that are know to be involved with the regulation of appetite and body weight to determine if some of the changes that are expected to occur after diet-induced weight loss do not occur after bariatric surgery. In addition, proteomic analysis will be used to uncover new protein biomarkers that are unique to surgical weight loss. The results of these studies will help explain why bariatric surgery is so effective in achieving long-term weight loss. Understanding how the central nervous system responds to bariatric surgery could help the development of alternative nonsurgical therapies for obesity and its metabolic complications.

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.

What data supports the effectiveness of the treatment Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) for obesity?

Research shows that Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are effective for long-term weight loss and improving obesity-related health issues. RYGB is considered a gold standard for sustained weight loss, and both surgeries lead to hormonal changes that help with diabetes remission and weight loss. ^{1 2 3 4 5}

Is bariatric surgery generally safe for humans?

Bariatric surgeries like Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are generally considered safe, but they can have complications. These procedures have improved safety over time, but some risks remain, such as gastrointestinal issues and potential complications after surgery. ^{6 7 8 9 10}

How does the treatment of Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) for obesity differ from other treatments?

Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) are surgical treatments for obesity that are considered more effective for long-term weight loss compared to other methods like very low calorie diets. RYGB is often used as a secondary procedure when other surgeries like gastric banding or sleeve gastrectomy do not yield satisfactory results, making it a unique option for patients needing further intervention. ^{5 11 12 13 14}

Research Team

Sharon L Wardlaw, MD

Principal Investigator

Columbia University

Eligibility Criteria

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

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

Treatment Details

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.

Participant Groups

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+

Findings from Research

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]

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]

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]

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]

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 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]

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) 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]

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]

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 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]

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]

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]

References

1. United States 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. [2018]

2. Netherlands 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. [2022]

3. England pubmed.ncbi.nlm.nih.gov

Updates in weight loss surgery and gastrointestinal peptides. [2018]

4. United States 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. [2021]

5. United States 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? [2018]

6. Italy 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. [2022]

7. Korea (South) pubmed.ncbi.nlm.nih.gov

Risk factors for early postoperative complications after bariatric surgery. [2022]

8. United States pubmed.ncbi.nlm.nih.gov

Gastrointestinal manifestations after Roux-en-Y gastric bypass surgery in individuals with and without type 2 diabetes. [2021]

9. Poland pubmed.ncbi.nlm.nih.gov

The role of alimentary and biliopancreatic limb length in outcomes of Roux-en-Y gastric bypass. [2022]

10. United States pubmed.ncbi.nlm.nih.gov

Is Bariatric Procedure Type Associated With Morbidity in Transplant Patients? [2022]

11. United States pubmed.ncbi.nlm.nih.gov

Unsatisfactory weight loss after vertical banded gastroplasty: is conversion to Roux-en-Y gastric bypass successful? [2004]

12. United States pubmed.ncbi.nlm.nih.gov

Conversion to Gastric Bypass After Either Failed Gastric Band or Failed Sleeve Gastrectomy. [2018]

13. United States pubmed.ncbi.nlm.nih.gov

Vitamin D status and supplementation before and after bariatric surgery: a comprehensive literature review. [2018]

14. United States 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. [2018]