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Understand the Role of Primary Care in Bariatric Surgery

Dr Toni Hazell Discusses the Management of Patients Undergoing Bariatric Surgery, Focusing in Particular on Aftercare for Patients Who Access Surgery Privately

Read This Article to Learn More About:
  • definitions of obesity and overweight, and the importance of nonstigmatising language
  • eligibility for bariatric surgery in the UK, with reference to clinical guidance
  • the role of primary care in the management of individuals who return from overseas after bariatric surgery.
Reflect on your learning and download our Reflection Record.

Obesity has been described as a public health emergency: around 60–80% of adults and 20–30% of children in most Western countries are now living with obesity or overweight.1 In 2021, the Health Survey for England estimated that 37.9% of adults in England were overweight but not obese, and 25.9% were classed as having obesity.2

Healthcare professionals may remember the days when private clinics gave out all manner of weight-loss ‘treatments’,3 including amphetamine-based drugs, thyroxine, and human chorionic gonadotrophin injections4—an area of prescribing that sometimes attracted the attention of the General Medical Council (GMC). In current practice, there are four options for the management of obesity in adults:5

  • diet and exercise
  • orlistat
  • glucagon-like peptide-1 receptor agonists (GLP-1 RAs)
  • surgery.
Bariatric surgery is the most effective intervention for weight loss, reducing not only weight, but also the risks of complications such as diabetes, hypertension, cardiovascular disease, and obstructive sleep apnoea.5–7 This article will focus on bariatric surgery, in particular recent changes in NHS access, and the difficult issue of safe and effective aftercare for those who access surgery privately, either in the UK or abroad. 

Defining Obesity and Overweight

Obesity and overweight are defined by body mass index (BMI), which is a patient’s weight in kilogrammes divided by their height in metres squared.8 The definitions of these weight categories are set out in the Table 1,5,8,9 and vary depending on whether the population is at a higher than average risk of obesity and overweight. Those with a South Asian, Chinese, other Asian, Middle Eastern, Black African, or African-Caribbean family background are considered to be at higher risk and prone to central adiposity.5 

Table 1: Classifying Overweight and Obesity in Adults5,8,9

Weight classBMI in kg/m2 (normal-risk population)BMI in kg/m2 (high-risk population[A])
Healthy weight 
Obesity class 1
Obesity class 2
Obesity class 3
[A] High-risk population refers to people of South Asian, Chinese, other Asian, Middle Eastern, Black African, or African-Caribbean family background—their referral requires using a lower BMI threshold (reduced by 2.5 kg/m2) compared with a normal-risk population
BMI=body mass index 

Issues with BMI

BMI is not a perfect measurement for a variety of reasons. It cannot be used in those who have had a limb amputated, and it does not consider the amount of fat versus muscle in the body or its distribution. Adding the use of waist circumference can sometimes improve risk assessment, as fat around the waist is more closely associated with metabolic risk than fat elsewhere.5,9,10 Healthcare professionals should consider this when presented with a professional athlete who apparently has obesity, but is in fact clearly very muscular with little body fat.

Use of Supportive Language

It is important to consider the language being used when engaging with individuals who are living with obesity or overweight. The term ‘morbid obesity’ is stigmatising, and should not be used;11 instead, when discussing weight with patients, supportive language should be used to avoid any weight bias or perceived discrimination, as stigmatising language may result in individuals avoiding seeking support.

Bariatric Surgery in the UK

In any healthcare system, access to bariatric surgery will be limited in one way or another; in the UK, this is due to decisions made by NICE and commissioning bodies,7 whereas in other systems, it may be influenced by the ability or willingness of the patient or their insurer to pay for the procedure. In July 2023, NICE carried out a review of the cost-effectiveness of its thresholds for bariatric surgery,12 which led to an update of NICE Clinical Guideline (CG) 189 on obesity.5 

Eligibility for Bariatric Surgery

Prior to July 2023, CG189 advised that those with a BMI of 40 kg/m2 or more (or 35–39.9 kg/m2 with related comorbidities) could be referred for bariatric surgery if all nonsurgical interventions had already been tried and the person was receiving management at a tier-3 obesity clinic.13 This created a barrier to referral that was, in some cases, insurmountable. A 2015 Public Health England survey showed that only 21% of clinical commissioning groups had a tier-3 weight-management service,14 and those that are available often have long waiting lists. Furthermore, until the current shortage of GLP-1 RAs resolves,15 there may be little that a tier-3 clinic can offer other than diet and exercise advice and orlistat, neither of which are an effective long-term strategy for significant weight loss.16

CG189 now recommends that adults can be referred for an assessment of suitability for bariatric surgery if they have ‘a BMI of 40 kg/m2 or more, or between 35 kg/m2 and 39.9 kg/m2 with a significant health condition that could be improved if they lost weight’, the only other requirement being that the patient will ‘agree to the necessary long-term follow-up after surgery’—there is no requirement for any previous referrals or treatments to have been tried.5 NICE does however recommend that, for the referral of high-risk populations, lower thresholds are used (see Table 1).5 

Consequences of Long Waiting Times

The changes to CG189 will allow more patients to be referred for bariatric surgery, although this will make little difference to public health if referral only places them on an ever-growing waiting list. An expansion in capacity is needed for both surgery and the necessary physical and psychological preoperative assessments. NHS waiting times vary by area, but it can take around a year from referral to the date of bariatric surgery.17 It is therefore unsurprising that many patients opt to have their surgery done privately, and it is increasingly common for patients to travel abroad for weight-loss surgery, which is significantly cheaper than having it done in the UK even after travel costs are considered.18,19 

Patients Returning to the UK After Bariatric Surgery Abroad 

The return of a patient to the UK after bariatric surgery abroad can be problematic for primary care practitioners because:18–20

  • documentation is often lacking or not in English
  • it is unclear how much preoperative assessment and counselling was done, and whether the choice of procedure was driven by a thorough clinical assessment or purely by cost
  • the patient may have complications, such as venous thromboembolism, resulting from the need to travel long distances soon after a major surgical procedure
  • patients who have bariatric surgery on the NHS will receive follow up in secondary care for 2 years—this is unavailable to those who have travelled abroad for surgery, and they will have no access to their surgeon if a complication occurs. In addition, these first 2 years of care are not commissioned in primary care in the NHS, and are often outside of a GP’s areas of expertise.

How Should GPs Respond to Patients Who Have Had Bariatric Surgery Abroad?

Gathering Information

The first step is to obtain as much information as possible. The GMC guidance Good medical practice states that GPs ‘should make sure that arrangements are made, wherever possible, to meet patients’ language and communication needs’,21 but it is the ‘where possible’ in this statement that causes problems, as the practicalities of getting the notes or discharge summary translated may vary by area. 

Guidance on interpreting and translation issued by NHS England in 2018 states: ‘Where patients register with a practice and are in possession of documents in languages other than English that relate to their health, these should be translated into English as soon as possible where there is an identified clinical need.’22 However, it does not state who is responsible for organising or paying for this; in any case, these services are usually commissioned locally in England,22 and arrangements are likely to differ between the devolved nations of the UK. In many areas, there is no funding for document translation, with services available only if practices or individuals are willing to pay for them.23,24 It would be sensible for practices to check their local integrated care board (ICB) arrangements and to have a policy on this issue.20 If no NHS-funded translation is available, then this policy may have to be that medical documentation must be professionally translated into English at the patient’s expense.

If a patient has sought your advice before travelling abroad for surgery, this would be a useful area to cover. If asked to justify the decision to make patients pay for their own translation costs, GPs could point to the Medical and Dental Union of Scotland webpage, which states: ‘Doctors and dentists are under no obligation to translate treatment records provided in a foreign language by a patient returning from abroad. Any costs associated with translation should in most circumstances be met by the patient’,25 or the practice may wish to obtain written confirmation from its ICB that there is no NHS funding to meet such costs.20

Navigating Clinical and Medicolegal Issues

Once GPs have the translated paperwork in hand, they will probably find that it requests a variety of blood tests, some to be done as often as monthly, and possibly including tests that are not usually carried out in NHS primary care and for which expert advice on their interpretation is not readily available.19,20 As mentioned earlier, patients who undergo bariatric surgery on the NHS receive the first 2 years’ worth of follow-up care from the bariatric clinic, which would take responsibility for requesting and interpreting any blood tests needed,5,19,20 and this is therefore an area in which GPs may not be experienced. If a patient has gone abroad because they are not entitled to bariatric surgery on the NHS or are not happy to wait for NHS timescales, then they will not have access to this care on the NHS19,20—and this puts the GP in a difficult position. If the local NHS clinic will not accept patients for follow up who have had surgery elsewhere (and many will not), then the GP has to either try and provide this care themselves, or refuse and signpost the patient to private follow up in the UK; this risks a complaint or referral to the GMC if the patient comes to harm as a result of a lack of follow up.19,20 

In this difficult clinical and medicolegal situation, any guidance is welcome and, in recent months, several local medical committees (LMCs) have published information for their constituent GPs.26,27 The advice is to tell the patient to seek private bariatric follow up in the UK for 2 years;27 some LMCs provide template letters to patients to explain the rationale behind this request,26 which reassure the patient that new symptoms that may be related to the surgery will be dealt with appropriately and that emergency treatment is available for any surgical complications, but that routine follow-up for the first 2 years is not available on the NHS. 

The medical defence organisations have also recognised that this is an emerging issue, and some have provided information for GPs in this situation.19,20 The Medical Protection Society (MPS)19 notes that the GMC21 advises GPs to ‘work within the limits of your competence’, and directs GPs to refer patients if postsurgery care is not within their competence. The MPS also highlights the risks involved in sharing care with a private clinician abroad, which may be increased as a result of differences in guidelines and regulatory requirements as well as a language barrier.19 A Medical Defence Union publication gives similar advice, adding that GPs should check what is commissioned locally and ask for this information in writing so that they can demonstrate that they have explored the NHS options before asking a patient to self-fund private care.20 Finally, the British Medical Association states that ‘if follow up is of a specialist nature, or not within normal general practice remit, the patient should be referred to the appropriate service in the UK for this follow up. If an appropriate service is not available, or rejects the referral, this should be directed to the local commissioner whose responsibility it is to commission the service’.28

Consulting Guidance and Seeking Specialist Advice

If a practice does choose to provide this follow up (which would usually be unresourced, unless there is a local enhanced service), then it may be wise to seek advice from a consultant, as the British Obesity & Metabolic Surgery Society (BOMSS) guidance only covers patients 2 years or more after surgery.29 The BOMSS guideline is useful for patients who have been discharged after their 2-year follow up, and gives clear advice about who needs which blood tests depending on the type of bariatric surgery they have had;29 this guidance should be read in conjunction with individualised advice from the patient’s surgical unit. 


Bariatric surgery is the most effective treatment for obesity, and has the potential to save lives and healthcare expenditure by preventing many of the medical complications of obesity. However, surgery is just one part of a larger treatment plan that involves physical and psychological care before and after surgery. It is important that patients who fund their own surgery, either in the UK or abroad, understand that they need to factor in the costs of this aftercare and that, without it, their surgery may be less effective. Support from LMCs should enable practices to be clear on what they do and do not have funding for, and to have the confidence to signpost patients to the private sector when NHS aftercare is not available. 

Useful Resources

For GPs:

For patients:BOMSS=British Obesity & Metabolic Surgery Society; GMC=General Medical Council 
Key Points
  • Obesity is a public health emergency, impacting around 60–80% of adults and 20–30% of children in most Western countries
  • There are currently four options for the management of obesity—diet and exercise, orlistat, GLP-1 RAs, and surgery
  • Bariatric surgery is the most effective intervention for weight loss, and also reduces the risks of complications such as diabetes and cardiovascular disease
  • Obesity and overweight are defined according to BMI thresholds
  • Individuals of South Asian, Chinese, other Asian, Middle Eastern, Black African, or African-Caribbean heritage are at increased risk of obesity
  • BMI is imperfect as it does not consider the amount of fat versus muscle in the body or its distribution; using waist circumference in addition can improve risk assessment
  • When discussing weight with patients, supportive language should be used, as stigmatising language may prevent individuals from seeking support.
  • Adults can now be referred for assessment if they have a BMI of 40 kg/m2 or more, or between 35 kg/m2 and 39.9 kg/m2 with a significant health condition
  • An increasing number of patients are having surgery privately in the UK or abroad, creating a complex clinical and medicolegal situation for GPs when they return
  • GPs should work within their competence, and refer patients if postsurgery care is outside their areas of expertise.

GLP-1 RA=glucagon-like peptide-1 receptor agonist; BMI=body mass index

Declaration of Interests

Dr Hazell contributed to the Patient website’s information for patients on this topic.