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What is the criteria for weight within NHSGGC

  • BMI ≥ 35 to ≤ 60kg/m2 
    • aged ≥ 18 to < 55 years old
    • Type 2 diabetes (confirmed diagnosis)
    • Type 2 diabetes diagnosed < 10 years
    • HbA1c ≤ 75 mmol/mol (9%)
  • BMI ≥ 35 to ≤ 60kg/m2 
    • sleep apnoea (confirmed diagnosis)
    • aged ≥ 18 to < 45 years old

Criteria last revised December 2021.

In addition to the above:

  • Complete a 12 week SWMS lifestyle programme, demonstrating a weight loss of at least 5kgs (11 pounds)
  • Attend a multidisciplinary pre-surgery assessment process, including seeing a dietitian, a nurse, psychology screening and a surgeon.
  • The surgeon will make the final decision if a patient is suitable. This will take into account a patient’s past medical history and other health professional recommendations.

Occasionally, you may be considered for surgery out with this criteria. For example; if you have an extenuating health or clinical issue which would be improved by weight loss surgery. This would be considered following a discussion with the SWMS team and the bariatric multi-disciplinary exceptional referral group.

What is the route for weight loss surgery?

Attendance at SWMS is the only way to be referred for weight loss surgery.

 Please see our referral section.

What type of surgery is offered?

  • Sleeve Gastrectomy – This involves converting your stomach into a long thin tube or ‘sleeve’. The stomach is stapled along its length in a vertical direction. The surgeon removes about 70% of your stomach during the procedure. The smaller stomach pouch, or sleeve, will reduce your ability to eat large portions. This should help you feel satisfied for longer with smaller food portions. This is a permanent procedure and cannot be reversed.
  • One Anastomosis Gastric Bypass (OAGB) – A smaller stomach is created which will restrict your food intake. A section (about a 1/3,) of your intestine is bypassed. The bypass surgery helps you lose weight by reducing the amount of calories your body can absorb. The surgery reduces hunger and creates fullness quickly, so the amount you can eat is less. Fewer vitamins and minerals (especially iron,) are absorbed as food passes through the intestine. This is a permanent procedure and highly unlikely to be reversed. The OAGB will only be offered to some individuals. This surgery may not be considered if you have a BMI >45 kg/m2 .

How is the surgery performed?

You will need to have laparoscopic (keyhole) surgery under a general anaesthetic.

What are the potential benefits of weight loss surgery

  • Long term weight reduction
  • Remission or improvement of type 2 diabetes
  • Improved cholesterol levels
  • Reduced blood pressure
  • Improved obstructive sleep apnoea (disturbed sleep)
  • Less joint pain
  • Better mobility
  • Reduction in medications
  • Improvement in mood and general quality of life 

How are you referred for surgery?

If you meet the criteria outlined above, and completed the SWMS 12 week lifestyle programme – demonstrating a loss of least 5kgs  (11 pounds,) you will be invited to a Surgery Information Session (SIS). Following this session, if you wish to proceed, you will be appointed for a surgical assessment with a Specialist Dietitian. If indicated, you may also see a Clinical Psychologist.

What happens next?

Following surgical assessment a report will be sent to the surgeon.

The surgeon will assess if you are suitable for surgery considering your past medical history and clinical risk. You will also require a pre-operative nursing assessment.

It is the surgeon who makes the final decision on surgery.

How does SWMS prepare you for weight loss surgery?

You will be required to attend “preparation for surgery groups”. These groups focus on dietary, eating behaviours and physical activity changes that will be required after surgery.

The surgery team physiotherapist can offer you advice about activity or mobility issues. In addition, there are Physiotherapy led SWMS activity classes at both chair based and moderate intensity levels available.

Some patients require pre-surgery psychological support if indicated.

What follow up support is offered after surgery?

SWMS offers an intensive 2 year follow up package. This includes individual and group appointments and also a patient support group.

Those who have had surgery via SWMS have the option of lifelong follow up after surgery if required.

How much weight loss can be expected after surgery?

The majority of weight loss after surgery happens within the first 6 months to 1 year. Often weight loss can be slower over the second year. On average, people can lose:

50-60% ‘excess’ body weight with a gastric sleeve

60-70% ‘excess’ body weight with a bypass

How much weight a person loses completely depends on the changes they make to their diet, activity levels and behaviour. Some can lose more weight than this; others may lose less.

It is not guaranteed that having weight loss surgery will reduce your weight/BMI to within the healthy range. Predicted weight loss outcomes are calculated individually using the patient’s pre-op weight/BMI.

If I have been through the SWMS Programme and been discharged – Can I Be referred directly for surgery?

No, all patients who meet criteria must be re-referred and complete the 12 week lifestyle programme demonstrating a loss of at least 5kgs (11 pounds,) during their current episode of care.

I have had weight loss surgery privately – Can I access follow up through SWMS?

Unfortunately, SWMS does not offer routine post-surgical follow up care for those who have had private weight loss surgery. SWMS can offer weight management support via the lifestyle programme, for those who have had private surgery if the person is; struggling to lose weight, at least 1 year post-op and medically stable.

Other factors to consider when thinking about weight loss surgery?

  • Smoking – tobacco use is a well documented surgical risk factor. Smoking can increase the risk of post-operative complications. The surgeon will not operate on a patient who is smoking or using electronic cigarettes (vapes). NHS Smoking Cessation can provide support.
  • Pregnancy – it is recommended that a female should not become pregnant until at least 12-18 months post-op. This allows time for weight loss to stabilise and ensure that they are able to eat a varied nutritious diet. Losing weight can increase fertility in some women, therefore contraception should be considered and discussed with your GP/Practice Nurse if appropriate.

Further information and useful links can be found below:

  • BOMSS – British Obesity and Metabolic Surgery Society.
  • BOSPA – British Obesity Surgery Patient Association. 
  • WLS Info – Weight Loss Surgery Information. 
  • BEAT – British charity for disordered eating.

For GP’s/Healthcare professionals: the link below provides guidance on nutritional pre/post op monitoring and supplementation, from the British Metabolic and Obesity Surgery Society (BOMSS).

British Obesity and Metabolic Surgery Society Guidelines on perioperative and postoperative biochemical monitoring and micronutrient replacement for patients undergoing bariatric surgery—2020 update – O’Kane – 2020 – Obesity Reviews – Wiley Online Library

If you have any questions about weight loss surgery after reading this information please contact a member of the SWMS team.