Long-Term Results at 10 Years of Pouch Resizing for Roux-en-Y Gastric Bypass Failure

Round 1

Reviewer 1 Report

Dear author(s),

In terms of ways to develop this manuscript further, the most important things that you could do are:

1. Abstract. The abstract section should clearly state the contribution of this research and what research gap it addresses. It should bring in more details about methodology used. Include population and sampling, and data analysis approach. Describing the theoretical framework that was adapted to frame the study would improve the manuscript.
2. Introduction. The introduction needs to be developed further to clearly establish the justification/importance of the new initiative and articulate the research problem and objective; these need to be specifically linked to the associated issues and problems. The introduction would benefit from a succinct description of what the manuscript is about and a stronger emphasis on the problem addressed by the research.
3. Literature review. Coverage of other relevant work is partly provided, however there is a lack of comment and critical review of this work - it is just a 'matter-of-fact' listing of relevant literature. Including a wider critical overview of the most recent literature would significantly contribute to the quality of the manuscript and would strengthen its academic perspective and scientific foundation. Much more critical analysis needs to be undertaken of the relevant literature and key points/issues identified which will underpin the rest of the manuscript. Try to include some latest journal article references published from 2018-2021 in the specific areas to improve the relevance and currency of the research. Extended literature review would help you also with addressing the issue of contribution of the manuscript.
4. Discussion.

·       The discussion section does not effectively advance the themes that the manuscript sets out to address. Perhaps this is due to not providing specific research questions. Suggestion: Provide more specific research questions then integrate the literature with the finding to provide a coherent argument in favor of the proposed research provided.

5. Conclusion. Conclusion section should be expanded to highlight the unique contributions of the manuscript and limitations of the research. It should include all main results in compact form, comments and their implications. The finding should be related to results from previous literature. The discussion and conclusion should make it clear how the research findings contribute to new knowledge.

 Overview. The manuscript is not developed in a coherent way. The manuscript needs further documentation on both, theoretical and literature review levels, in order to enhance its contribution to the scientific area. Furthermore, the manuscript appears to miss significant issues with respect to focus, balance between theoretical background, literature review, and original research findings supporting this case study. My suggestion is that the manuscript needs extended restructuring in terms of

• more convincing arguments and documentation of the originality and the value of this particular research,
• the methodology and design of the research,
• a coherent presentation and interpretation of the findings and provide an argument that supports the significance of the research in comparison to what is already known about this research problem,
• the conclusions and implications for further research on this topic, i.e. how the results of the research can be used for future research and practice, and
• Plagiarism check results:
• /* Similarity check with iThenticate revealed a similarity index of 33%, which is considered not appropriate. A maximum of around 60 quoted words is accepted per paper. There are papers with over 60 words. No previously copyrighted material was used.

Best wishes

Comments for author File: Comments.zip

Author Response

Dear Reviewer,

Thank you for your appraisal.

Here you can find the answers to the suggested major revisions.

In terms of ways to develop this manuscript further, the most important things that you could do are:

1. Abstract. The abstract section should clearly state the contribution of this research and what research gap it addresses. It should bring in more details about methodology used. Include population and sampling, and data analysis approach. Describing the theoretical framework that was adapted to frame the study would improve the manuscript.

Background: Roux-en-Y gastric bypass is currently one of the most performed bariatric procedures and it is associated with rapid weight loss. However, weight loss failure and weight regain after RYGB occurs in approximately 30% and 3-5% of patients respectively and represent a serious issue. RYGB pouch resizing is a surgical option that may be offered to selected patients with RYGB failure. The aim of this study is to assess long-term results of pouch resizing for RYGB failure. As long result of this technique are lacking we aimed to asses the rate of failure at more than ten years in a prospective cohort of individuals undergoing pouch resizing.

Materials and Methods: From February 2009 to November 2011, 20 consecutive patients underwent gastric pouch resizing for RYGB failure in our tertiary bariatric center. The primary outcome of this study was the rate of failure (%EWL < 50% with at least one metabolic comorbidity) after at least 10 years from pouch resizing. The secondary endpoints were the assessment of the evolution of the associated medical problems including type 2 diabetes, hypertension, obstructive sleep apnea syndrome, osteo-artritis and gastroesophageal reflux disease (GERD). Data were retrieve from a prospective database and updated at the time of the study.

Results: Twenty patients (18 women (90%)) were included and seventeen (85%) joined the study. The failure rate of pouch resizing was 47%. Mean %EWL and mean BMI were 47%, and 35.1kg/m² respectively. Some of the persistent co-morbidities further improved or resolved after pouch resizing. Seven patients (41%) presented GERD requiring daily PPI with a significantly lower GERD-HQRL questionnaire score after pouch resizing (p<0.001).

Conclusion: Pouch resizing after RYGB results in a failure rate of 47% at 10-years follow-up while the resolution of comorbidities is maintained over time despite a significant weight regain. Results of this study should be confirmed in a larger multicentrer trial.

1. Introduction. The introduction needs to be developed further to clearly establish the justification/importance of the new initiative and articulate the research problem and objective; these need to be specifically linked to the associated issues and problems. The introduction would benefit from a succinct description of what the manuscript is about and a stronger emphasis on the problem addressed by the research. 

Bariatric surgery (BS) has developed enormously over the last two decades in concomitance with the obesity epidemic (1,2). Prospective studies have shown that BS is associated with significant and sustained weight loss, remission or improvement of obesity associated medical problems as well as reduced mortality, stroke, and cancer risk (2). Several longitudinal studies have shown the short- and medium-term efficacy of Roux-en-Y gastric bypass (RYGB) and these results have been confirmed by meta-analyses (3). However, very few data are available concerning the results of the RYGB beyond 10 years. Weight loss failure or regain are common in the long-term (30% and 3-5% respectively) (4,5) and they are often associated with the recurrence or the development of new obesity associated medical problems (4,6). The definition of failure is not consensual in the literature; however, most of the authors agree on a loss of excess weight (%EWL) of less than or equal to 50%, associated with the recurrence of one or more obesity-related medical problems (3,6). The prevalence of bariatric surgery failure is largely unclear, mainly because an all-encompassing, unambiguous definition is still lacking. Adams et al reported in a controlled study that 30% out of 418 participants with a RYGB showed <20% of total body weight loss at 12 years from surgery (7). A recent study based on the Scandinavian Obesity Surgery Registry showed that the prevalence of RYGB failure 5 years after surgery was 23% (8). These figures indicate that RYGB failure at mid- and long-term is an important issue in bariatric surgery.

Gastric pouch resizing (GPR) is a surgical option that may be offered to selected patients with RYGB failure. The principle is to restore restriction by decreasing the capacity of the stomach. Given the high number of RYGB performed yearly worldwide, the fact that this procedure has been introduced more than four decades now, the rate of failure that increases with time from the index surgery, the possibility of restore restriction has been explored by bariatric surgeons in the past. .However, there is conflicting evidence in the literature regarding the efficacy and the safety of GPR (9,10). Furthermore, the results of this surgical option have never been reported in the long-term. 

As we previously reported the results of GPR We have previously reported the short-term results of this technique in a series of 20 consecutive patients (11), we aimed in this study, to investigate the rate of failure in this same cohort of individuals  report the long-term results of GPR in the same patients with a minimum follow-up of 10 years.

We thank the reviewer for her/his remark. The introduction has the classical funnel shape and we added a few sentences to strengthen the main topic, namely the large load of RYGB procedures that have been performed, the need to offer therapeutical alternative to individuals with failure and the goal of the paper that reports the results at 10 years of this surgical option. We also stressed that this information is lacking in the literature. This is we think the paper may “fill the gap” of knowledge in this field.

1. Literature review. Coverage of other relevant work is partly provided, however there is a lack of comment and critical review of this work - it is just a 'matter-of-fact' listing of relevant literature. Including a wider critical overview of the most recent literature would significantly contribute to the quality of the manuscript and would strengthen its academic perspective and scientific foundation. Much more critical analysis needs to be undertaken of the relevant literature and key points/issues identified which will underpin the rest of the manuscript. Try to include some latest journal article references published from 2018-2021 in the specific areas to improve the relevance and currency of the research. Extended literature review would help you also with addressing the issue of contribution of the manuscript.

We thank the reviewer for her/his remark but the literature on this topic is extremely scanty and there is no report of GPR at 10 years follow-up as in the present study. We added critical comments to what previously reported as demanded.

1. Discussion. 

• The discussion section does not effectively advance the themes that the manuscript sets out to address. Perhaps this is due to not providing specific research questions. Suggestion: Provide more specific research questions then integrate the literature with the finding to provide a coherent argument in favor of the proposed research provided.

We thank the reviewer for her/his remark. The research questions were settled in the M&M section, i.e. primary and secondary outcomes of the study. The critically reviewed selective part of the discussion to strengthen what the paper adds to the current knowledge filling the gap on the long-term results of this technique. We believe that these results may be of help for the clinician dealing with individuals presenting with RYGB failure that may be candidate to GPR.

1. Conclusion. Conclusion section should be expanded to highlight the unique contributions of the manuscript and limitations of the research. It should include all main results in compact form, comments and their implications. The finding should be related to results from previous literature. The discussion and conclusion should make it clear how the research findings contribute to new knowledge.

 Overview. The manuscript is not developed in a coherent way. The manuscript needs further documentation on both, theoretical and literature review levels, in order to enhance its contribution to the scientific area. Furthermore, the manuscript appears to miss significant issues with respect to focus, balance between theoretical background, literature review, and original research findings supporting this case study. My suggestion is that the manuscript needs extended restructuring in terms of

• more convincing arguments and documentation of the originality and the value of this particular research,

The main originality of this study is that there is no other report in the literature with such a long follow-up and with a prospective baseline data. This point has been stressed throughout the paper as suggested.

• the methodology and design of the research,

The structure of M&M section was changed and a paragraph on study design was added insisting on the type of study, patients’ cohort, endopoints and methods used to collect data.

Study design.

This is a single-center longitudinal cohort study. The short-term results of this cohort have been published previously and this study replicates the long-term follow-up of this longitudinal cohort (11). Data were retrieved retrospectively from a prospective held database in our tertiary referral bariatric center and updated with a minimum follow-up of 10 years. This study was declared to the Commission Nationale Informatique et Liberté (CNIL 6009701).

From February 2009 to November 2011, 20 consecutive patients underwent GPR for RYGB failure. All patients in our study had the RYGB performed with a 150 cm long alimentary limb and a 50 cm long biliopancreatic limb and a 10-12 mm hand-sewn gastro-jejunostomy. The indications for GPR were progressive weight regain with recurrence of at least one comorbidity in 13 patients (65%) and insufficient weight loss (%EWL <50%) in 7 patients (35%). Both RYGB and GPR were performed laparoscopically in all patients. All data were collected prospectively.

All patients were examined in the outpatient’s clinic between July and September 2021 after 10-years follow-up from GPR, to evaluate weight loss and obesity medical associated problems evolution.

The primary endpoint was the long-term failure rate of GPR, defined as a composite endpoint including <50% of excess weight loss (%EWL), and/or the presence of at least one obesity medical associated problem (persistent, recurrent after remission or improvement, or de novo) among type 2 diabetes (T2D), dyslipidemia, hypertension (HT); osteoarthritis (OA), obstructive sleep apnea syndrome (OSAS). The secondary endpoints were the assessment of the evolution of the associated medical problems (T2D; HT; OSAS, OA, GERD). The presence of associated medical problems was classified as recurrence (in patients for whom a remission had been proven during follow-up) or de novo onset (in patients not presenting the comorbidity before surgery).

Patients’ informed consent was obtained in all cases. To investigate Gastroesophageal Reflux Disease (GERD) patients were also asked to complete the Gastroesophageal Reflux Disease (GERD-HRQL) Health-Related Quality of Life Scale (Appendix 1) which focuses on pyrosis-like symptoms, dysphagia, effects of medication and consequences of GERD on patients' daily life (12). All patients who regained weight after RYGB underwent psychiatric and nutritional assessment prior to re-operation. Data on %EWL after GPR were calculated from the preoperative weight at the time of RYGB. The method to realize the volumetric assessment of the gastric pouch was reported previously (11).

• a coherent presentation and interpretation of the findings and provide an argument that supports the significance of the research in comparison to what is already known about this research problem,

We implemented the discussion adding a more critical review of other authors’ studies and insisted on the major strength of the present study which is the long term follow-up. We would also like to stress that literature is quite scanty in bariatric surgery long-term follow-up where long term is > 10 years. When treatment of failed cases is considered no long-term data are available.

• the conclusions and implications for further research on this topic, i.e. how the results of the research can be used for future research and practice, and

We suggested in the conclusion the need for further series reporting long-term results in patents experiencing failure after RYGB.

5. Conclusions

     GPR may be an attractive option for failed weight loss in selected patients with a dilated gastric pouch. The efficacy of this option has been proven in the short term and this study shows that 53% of patients still have good results in the long term when considering weight loss. Moreover, a substantial improvement in GERD related symptoms and in obesity associated medical problems has been highlighted after GPR. Larger, multicentric, long-term follow-up studies should be performed to confirm these results.

• Plagiarism check results:
• /* Similarity check with iThenticate revealed a similarity index of 33%, which is considered not appropriate. A maximum of around 60 quoted words is accepted per paper. There are papers with over 60 words. No previously copyrighted material was used. 

The results of the iTheticate revealing similarity are certainly because the M&M section of this study overlaps with other studies of our group on bariatric surgery. The section on comorbidities, weight loss and the definition of failure was extensively reformulated.

Reviewer 2 Report

Drai and colleagues resent data on 10 year follow up of patients that received pouch resizing following RYGB.  The data demonstrate mixed outcomes with a failure rate of 47% as defined by their criteria.  A strength of the paper despite the small sample size is the length of the follow up. I have only one suggestion.  The authors state that the indications for GPR were progressive weight regain with recurrence of at least one comorbidity in 13 patients (65%) or insufficient weight loss (%EWL <50%) in 7 patients (35%).  It would be interesting to present the results for these two groups separately as well.  Did the effect of GPR vary depending on the criteria reached for inclusion?

Author Response

Dear Reviewer,

Thank you for the time and effort she/he put in reviewing our work.

We tried to compare the two population but results were not consistent with any substantial difference mainly due to the small size of the sample.

We believe that this question should be investigated in a larger multicenter study as it may be possible that patient showing good initial results may behave differently from those who present with primary insufficient weight loss.

Round 2

Reviewer 1 Report

Overall, the revised manuscript adds and improves upon the first. I was generally satisfied with the authors' responses to my questions and comments. Therefore, I recommend publishing this article as it has the necessary scientific and methodological entity that would contribute to the creation and advancement of knowledge in the discipline.