|
 
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| ORIGINAL ARTICLE |
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| Year : 2023 | Volume
: 2
| Issue : 2 | Page : 68-78 |
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Patient pathways to bariatric surgery: What preoperative medical weight management programs exist globally – Results of an international survey
Danielle Clyde1, Maria Boland1, Leo R Brown1, Gerard McCabe1, William Cambridge1, Kerry Aitken2, Gillian Drummond3, Brian Joyce3, Andrew de Beaux1, Bruce Tulloh1, Osama Moussa4, Wah Yang5, Brij Madhok6, Peter J Lamb1, Kamal Mahawar7, Andrew G N. Robertson1
1 South East Scotland Bariatric Service, Royal Infirmary of Edinburgh; Clinical Surgery, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
2 Fife Adult Weight Management Service, Victoria Hospital, Kirkcaldy, United Kingdom
3 South East Scotland Bariatric Service, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
4 Division of Surgery, Imperial College London, St Marys Hospital, London, United Kingdom
5 Department of Metabolic and Bariatric Surgery, First Affiliated Hospital of Jinan University, Guangzhou, China
6 Department of General Surgery Royal Derby Hospital, Derby, United Kingdom
7 Bariatric Unit, South Tyneside and Sunderland NHS Foundation Trust, Sunderland, United Kingdom
| Date of Submission | 06-Feb-2023 |
| Date of Acceptance | 28-Mar-2023 |
| Date of Web Publication | 21-Jul-2023 |
Correspondence Address:
Mr. Andrew G N. Robertson
Department of General Surgery, Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, Scotland
United Kingdom
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/jbs.jbs_3_23
Introduction: Bariatric surgery is an accepted treatment worldwide for patients with obesity due to its proven metabolic effects. However, there are variations worldwide in clinical criteria that must be met to qualify for surgery. This study aims to explore globally established practice and opinions on preoperative workup for bariatric surgery. Materials and Methods: A review of literature and international guidelines was performed by a multidisciplinary team and used to develop an online questionnaire survey. This was distributed to bariatric professionals electronically. Results: Two hundred and forty-four bariatric health-care professionals from 224 medical centers across 57 countries completed the survey. The majority of respondents were surgeons (67.2%), and the remainder were other multidisciplinary professionals. Over half of medical centers were public hospitals (50.8%), with most performing over 200 procedures per year (30.3%). Only 68.4% (n = 167) of respondent hospitals used recognized referral guidelines; however, 81.9% felt that there should be written referral criteria (P < 0.001). In 71.3% (n = 172) of respondent units' patients underwent a Medical Weight Management Programme (MWMP) as part of their preparation for surgery. Significant differences were identified worldwide in the criteria used to determine progression to surgery (P < 0.001), time spent in MWMP prior to surgery (P < 0.001), and the roles of members forming the bariatric multidisciplinary team (P = 0.006). Conclusion: This study has identified significant variation in global bariatric surgery practices and highlights the responsibility that societies such as the International Federation for the Surgery of Obesity and Metabolic Disease (IFSO) and the Upper Gastrointestinal Surgery Society have in promoting universal clinical guidelines.
Keywords: Bariatric and metabolic surgery, medical weight management services, pre-operative patient preparation
How to cite this article:
Clyde D, Boland M, Brown LR, McCabe G, Cambridge W, Aitken K, Drummond G, Joyce B, Beaux Ad, Tulloh B, Moussa O, Yang W, Madhok B, Lamb PJ, Mahawar K, N. Robertson AG. Patient pathways to bariatric surgery: What preoperative medical weight management programs exist globally – Results of an international survey. J Bariatr Surg 2023;2:68-78 |
How to cite this URL:
Clyde D, Boland M, Brown LR, McCabe G, Cambridge W, Aitken K, Drummond G, Joyce B, Beaux Ad, Tulloh B, Moussa O, Yang W, Madhok B, Lamb PJ, Mahawar K, N. Robertson AG. Patient pathways to bariatric surgery: What preoperative medical weight management programs exist globally – Results of an international survey. J Bariatr Surg [serial online] 2023 [cited 2023 Sep 29];2:68-78. Available from: http://www.jbsonline.org/text.asp?2023/2/2/68/382113 |
| Introduction | |  |
Worldwide obesity rates have tripled since 1975; in 2016, 650 million people worldwide were clinically obese.[1] This equates to 13% of all adults, with obesity and its consequences now responsible for more deaths than starvation.[2] Bariatric surgery was initially developed as a treatment for patients affected by obesity, with a body mass index (BMI) of 35 kg/m2 or higher.[3],[4] Extensive research has shown that bariatric surgery is a safe and effective intervention in this high-risk patient group and now more than 500,000 bariatric procedures are performed worldwide each year.[5],[6],[7]
Recently, the additional beneficial metabolic effects of bariatric surgery have been demonstrated in patients with concurrent comorbidities such as type 2 diabetes mellitus (T2DM).[8],[9] In this subset patient group, remission of T2DM – irrespective of weight loss – has been demonstrated, resulting in these operative interventions being considered under the universal term “bariatric and metabolic surgery” (BMS).[8],[9],[10]
Worldwide clinical guidelines on qualifying patient criteria vary; the prerequisite BMI is often set lower in countries with a predominantly Asian population where rates of obesity-related comorbidities are often higher than in a comparative Caucasian population.[11],[12] In addition to variations in patient qualifying criteria, worldwide variations in the use of preoperative screening, investigation, and the use of medical weight management programs (MWMPs) have also been reported.[13],[14] As a result, discrepancies in time and cost of preoperative workup are to be expected between health-care systems.[15] Successful patient participation in preoperative MWMPs forms a prerequisite to “qualify” for surgery in many bariatric surgery centers. Differing opinions on the value added by these programs is evident with some groups reasoning that they play a key role in preparing patients for BMS, while others argue that they exist only to ration access to surgery.[14]
Variation in worldwide practice reflects a lack of robust evidence of how patients being considered for BMS should be investigated and managed in the preoperative phase. In order to better determine what this should be, a greater understanding of currently established practices in countries across the world is required. This article will report the findings of a comprehensive global survey of health-care professionals involved in the provision of BMS to demonstrate notable differences in preoperative practices including patient preparation and criteria for progression to surgery.
| Materials and Methods | | |
Survey design
A multidisciplinary bariatric team, representing the Upper Gastrointestinal (GI) Surgery Society (TUGSS): A global GI community, developed an online questionnaire survey. This involved members of the weight management programs/preoperative workup programs in the UK. The survey was developed using the survey production website Google Forms™. The questionnaire was created from a literature search and from reviewing international guidelines for preparation for bariatric surgery. The survey was subsequently modified by multidisciplinary team members of TUGSS. The questions were adapted to help categorize the data succinctly for collection and analysis. The full questionnaire is provided in Appendix 1.
Survey distribution
TUGSS distributed the survey to international multidisciplinary professionals in bariatric surgical services, and advertisement of the survey was posted on social media accounts to increase participation. Survey participation was voluntary, and data were analyzed anonymously. A reminder E-mail was sent weekly and repeated advertisement on social media was posted. The survey was open for a period of 12 weeks (April 7, 2022–June 30, 2022), decided by rate of participation.
Survey analysis and statistics
Data were then exported to a Microsoft Excel (Redmond, Washington, USA) worksheet for further analysis. A Checklist for Reporting Results of Internet E-Surveys checklist for the study was completed [Appendix 2].[16]
Statistical analysis was performed using GraphPad Prism 9.0TM software (San Diego, CA, USA). Categorical variables were analyzed using Chi-square tests. Continuous variables were analyzed using paired t-tests. Results from the questionnaire are presented as percentages throughout. Statistically significant results were considered when P < 0.001.
| Results | | |
Respondent demographics
There were a total of 245 respondents to the survey [Appendix 1]. One response was excluded as the country was not identifiable and questionnaire was incomplete. A total of 244 respondents were included, each from a different medical center across 57 countries [Table 1]. Our study reports 71% of respondents felt that preoperative weight loss was a positive predictor for better surgical outcomes. Responses were received from units performing <50 bariatric procedures per year (20.1%), between 50 and 100 (25.4%), over 100 (22.5%), and over 200 procedures per year (30.3%).
Preoperative protocols
Respondents were asked about the current practice of proceeding to surgery in their bariatric units. The majority of centers (85.2%) required approval following multidisciplinary team (MDT) discussion, 58.6% of centers required patients to achieve a weight loss target (this varied between centers), and 73.4% of centers required evidence of smoking cessation. A further 86.1% required participation in psychology assessment, with this being routine in 71.3% of centers. Details about the exact content of the psychology assessment are out with the remit of this study.
There were significantly higher rates of psychology approval (P = 0.027) requirements in the public sector; however, weight loss targets (P = 0.056), smoking (P = 0.381), and MDT approval (P = 0.720) did not vary based on unit's funding status. The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) and/or national guidelines were formally followed by 81.6% (199/244) of respondent centers, with 51.6% (126/244) of centers modifying these guidelines in some way. The results of current international practices are summarized in [Table 2] and [Table 3]. | Table 3: Summary of current international bariatric practice and opinion by continent
Click here to view |
Time spent in preparation for surgery also varied between the centers. Respondents reported that more than 27.8% (n = 67) of patients currently undergo 6 months or greater preparation prior to surgery, while only 17.1% (n = 41) thought that this was an acceptable period of time. Overall respondents believed that preparation time should be significantly shorter than current practice [P = 0.0223, [Figure 1]]. Comparison between public and privately funded systems showed that the time spent in preparation for surgery was significantly shorter in the private sector (P < 0.001). | Figure 1: Representation of perceived required perioperative preparation time
Click here to view |
Desired mandatory prerequisites to surgery
Study respondents were asked what they felt should be a mandatory requirement for progression to surgery and how this compared with current practice [Figure 2]. The main differences in professional views and current practices lay in whether the use of psychological assessment (P < 0.001), delivery of perioperative education program (P < 0.001), and patient participation in a MWMP (P = 0.043) should be mandatory prior to consideration of surgery. | Figure 2: Current criteria for patients to progress from MWMS to bariatric surgery. MWMS: Medical weight management services
Click here to view |
Weight management programs
In 71.3% (n = 172) of respondent units' patients underwent a Medical Weight Management Programme (MWMP) as part of their preparation for surgery. Preoperative weight management programs were more commonly utilized in public (77.9%) than mixed (67.9%) or private sector units (60.9%, P = 0.045). Educational elements were used in 69.7% of respondent programs, with these being routine practice in 59.0% of these centers. The education program was delivered in a number of ways including multisession, one-to-one teaching, seminars, and online modules. The individuals delivering this educational program also varied including dietitians, consultant surgeons, psychologists, nurses, and perioperative care practitioners. The provision of educational classes (P = 0.357) and coaching (P = 0.449) did not vary between public and private sectors.
Multidisciplinary team members
Variation between centers was also seen in the individuals delivering the bariatric service. Publicly funded bariatric units had higher representation of specialist nursing (P = 0.043) where bariatric anesthetists were more frequently in attendance at multidisciplinary meetings in the private sector (91.5% vs. 73.2%, P = 0.006). Survey respondents were asked to identify the clinical team members who participate in MDT meetings, as well as those clinicians they believe should attend MDT discussions prior to bariatric surgery. Almost all survey respondents, 96.7% (n = 227), stated that bariatric surgeons currently attend the MDT, while 97.9% (n = 233) felt that they should attend. The biggest difference seen between those who currently attend MDT discussions and those who believed valuable at these discussions was seen for bariatric coaches. Overall, 34.8% of respondents stated that they did while 49.4% of respondents believe that they should attend. Similarly, only 57.8% and 48.1% of respondents stated that nurse specialists and exercise therapists, respectively, attend their MDT. However, 71.5% believed that nurse specialists should attend MDT discussions, and 61.4% believed that exercise therapists should attend [Figure 3]. | Figure 3: Representation of perceived required members of a bariatric surgery service. MDT: Multidisciplinary team
Click here to view |
Service structure
In the 183 centers where more than one hospital filtered into a single bariatric unit, only 50.3% (n = 92) of the referral guidelines were standardized between the tributary hospitals. Only 68.4% (167/244) of respondent hospitals had formal written referral guidelines; however, 82.0% (200/244) of centers felt that there should be formal written referral criteria (P < 0.001).
| Discussion | | |
This study has demonstrated significant differences in international practices regarding patient preparation for bariatric surgery and referral criteria to progress from medical weight management services (MWMS) to operative management. This is one of the only international multidisciplinary studies focusing on patient preoperative preparation and referral criteria, which also sought the opinion of the specialist audience.
This study has demonstrated significant differences in current bariatric surgery practice worldwide. One noticeable difference was the role of members included in the Bariatric MDT; only 57.8% of respondents had nurse specialists, 48.1% had exercise therapists and 59.0% had bariatric specialist physicians. Variation in resources and the subspecialist nature of bariatric surgery likely reflects these observed differences. Despite these differences, the general consensus was that bariatric coaches, nurse specialists, and exercise therapists should be included in the bariatric MDT.
Evidence from systematic reviews and meta-analyses are generally supportive of the beneficial effects of a bariatric MDT team.[17],[18] A systematic review found that intensive MDT input preoperatively and postoperatively increased postoperative weight loss, in addition to improving symptoms of depression and anxiety, quality of life, diastolic blood pressure, and resting heart rate.[18] While the benefits of both bariatric surgery and the utilization of an MDT are well recognized, there is no consensus over which members should make up the team. Recently published guidance from the British Obesity and Metabolic Surgery Society and the American Society for Metabolic and Bariatric Surgery recommend that a metabolic physician, bariatric surgeon, and dietitian should be integral members of the MDT team.[19],[20],[21] These societies recognize that in addition to these core members, there are a number of additional personnel who often have an important role in the multidisciplinary management of bariatric patients including bariatric anesthetists, psychologists, clinical nurse specialists, gastroenterologists, and many others.[20],[21] However, a lack of research on the impact that each individual member adds to the MDT has limited any recommendation that these individuals should be included in the core bariatric MDT.
For patients progressing from MWMS to obesity surgery, criteria again varied worldwide. While the majority required a majority MDT decision, significant differences in requirements for psychological assessment, smoking cessation, participation in perioperative education programs, and application of weight loss targets were observed.
Evidence regarding the value of mandatory preoperative weight loss targets is conflicting. Evidence regarding the value of mandatory preoperative weight loss targets in order to progress to surgical management is conflicting. Our study reports that 71% of respondents felt that if patients could demonstrate evidence of preoperative weight loss then this would predict better surgical outcomes. Preoperative weight loss can be used as a surrogate marker of motivation and compliance with the MWMP.[22],[23] It has been reported that preoperative weight loss is associated with greater weight loss postoperatively and can be used to help to identify patients who would have better compliance after surgery.[22],[23] In contrast, when focusing on operative outcomes and complication rates, evidence suggests that there is no benefit from the application of mandatory preoperative weight loss.[24]
Mental health disease is well recognized in individuals seeking bariatric surgery.[25],[26] The goal of presurgical psychological assessment is not limited to identifying any psychiatric illness but to evaluate the mental health stability of the patients to undergo surgery, assess their level of motivation for the surgery, and evaluate their level of the adherence to the presurgical lifestyle modifications.[25],[26] Psychological assessment was another observed variation in routine practice among our respondent centers; 89% required patient participation in psychology assessment to proceed to surgery, while only 72% felt that this should be mandatory to proceed to surgery. Previous meta-analysis has suggested that there is inconsistent evidence regarding the association between preoperative mental health conditions and postoperative weight loss.[25] However, a separate systematic review suggested that behavioral interventions appear to improve weight loss at 12 months after bariatric surgery.[27]
An interesting observation was the significant difference in time spent in preparation for surgery between public and private health-care systems. While this is unsurprising with access to treatment in the public health-care systems likely to be subject to rationing in order to meet the demands of an entire population, in the private settings, these limitations in resources will be less significant. This observation raises an important issue surrounding access to surgery; bariatric surgery has been proven to be an effective treatment for patients with obesity, with associated improvement or reversal of associated comorbid conditions.[8],[9],[10] This questions whether mandatory time spent participating in MWMPs prior to progression for consideration of surgery is appropriate for this patient population.
A limitation of our study design means that there is a lack of validation of submitted data with true clinical practice within each respondent unit. In addition to this, we are not able to give a precise response rate due to the relative anonymity of our questionnaire design. However, the objective of this study was to capture variations in current international practice, and with a response rate of 244 from 57 countries/regions, we believe that our results are a good reflection of global practice.
| Conclusion | | |
This international study has demonstrated significant differences in bariatric surgery practice worldwide. It has also highlighted differences in what bariatric professionals feel is important for patients to achieve prior to progression to surgery as well as who they believe should make up the MDT. Although we have presented results reflecting current common international practice, we would caution that this may not necessarily reflect gold standard practice. We hope that our results will create new opportunities for research to address this gap in the literature as well as empower international surgical societies such as the International Federation for the Surgery of Obesity and Metabolic Disease (IFSO) to promote guidelines demonstrating best practice.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
| Appendixes | | |
Appendix 1: Survey questions (formatted from Google Forms™)
Do you work in a bariatric surgical service?
Yes No
What is your job role?
Consultant/fully trained bariatric surgeon
Dietician
Nurse Specialist
Psychologist
GP
Bariatric Physician
Exercise therapist/therapy
Other
If selected other above please specify
What country do you work in?
What is the name of your unit? (this will be anonymized)
Is your practice private/public or mixed?
Number of surgical bariatric procedures performed by unit a year (pre-COVID)
0–50
50–100
100–200
Over 200
Do your patients have to complete a Medical Weight Management Program in your service?
Yes No
Do you think patients should have to complete a Medical Weight Management Program in your service?
Yes No
What is your criteria for patients to be able to have bariatric surgery?
Achieve a weight loss target
Smoking cessation
Psychology assessment
MDT meeting
IFSO/national guidelines
Modified IFSO/national guidance
Completing an educational program
Other criteria (please specify)
If achieving weight loss is required, what is the target?
Weight maintenance
2.5%
5%
10%
Other (please specify)
If psychology assessment is required, is this routine or selective?
If psychology assessment is selective, how are these patients identified?
Do your patients have to attend an educational program?
Yes No Selective
Please expand on what your educational program includes if your unit has one
Do your patients have to have an OGD?
Yes No Selective
Does your patient preparation include
Dietician
Nurse Specialist
Psychologist
GP
Bariatric physician
Exercise therapist/therapy
Bariatric surgeon
Bariatric anesthetist
Educational classes
Coaching
Other (please specify)
On average, how long is preparation per patient (excluding COVID delays)?
<1 month
1–3 months
3–6 months
6–12 months
>12 months
How long do you think patient preparation should be (excluding COVID delays)?
<1 month
1–3 months
3–6 months
6–12 months
>12 months
Does your service have written referral criteria for surgery?
Yes No
Do you think your service should have written referral criteria for surgery?
Yes No
How many hospitals/regions drain into your service?
1
2–3
>3
Are those referral pathways standardized?
Yes
No
What do you believe should be the minimum criteria to progress to bariatric surgery?
Weight maintenance
Weight loss 2.5%
Weight loss 5%
Weight loss 10%
Weight loss other (please specify)
Mandatory psychological assessment
Selective psychological assessment
Mandatory smoking cessation
IFSO criteria
National guidelines/criteria
Modified IFSO/national guidelines
Unanimous MDT agreement
Majority MDT agreement
Routine OGD
Selective OGD
Education program
Coaching
Do you think meeting weight loss criteria predicts a better postoperative outcome?
Yes
No
If your service has weight loss targets, what happens to people who fail to meet those targets?
Remain in service
Transfer to a follow on service
Leave the service
Who are the minimum members you think are required for patient preparation for surgery?
Dietician
Nurse specialist
Psychologist
GP
Bariatric physician
Exercise therapist/therapy
Bariatric surgeon
Bariatric anesthetist
Coaches
Other (please specify)
This checklist has been modified from Eysenbach G. Improving the quality of Web surveys: the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). J Med Internet Res. 2004 Sep 29;6(3):e34 [erratum in J Med Internet Res. 2012; 14(1): e8.]. Article available at https://www.jmir.org/2004/3/e34/; erratum available https://www.jmir.org/2012/1/e8/. Copyright© Gunther Eysenbach. Originally published in the Journal of Medical Internet Research, 29.9.2004 and 04.01.2012.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/2.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3]
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