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Mal Fobi’s Corner

Rediscovering the wheel in reporting on weight loss and other outcomes after BMS

What differentiates surgical treatments from lifestyle changes; diets, pharmacotherapy and behavior modification are long-term weight loss maintenance and long-term amelioration of comorbidities

Publications on outcomes of bariatric metabolic surgeries (BMS) are going through the phase of rediscovering the wheel. Obesity is a life long disease. From the later half of the 70s through the early nineties, the field of BMS was characterised by introduction of surgical procedures that were claimed to be effective and popularised because of observed initial significant weight loss in the first year only to be discarded a few years later because of poor weight loss maintenance and/or significant weight loss regain. What differentiates surgical treatments from lifestyle changes; diets, pharmacotherapy and behavior modification are long-term weight loss maintenance and long-term amelioration of co morbidities.

This article was authored by Mal Fobi MD, Mohak Bariatric and Robotic Surgery Centre and Saims Jio University Indore, India

It became obvious to bariatric surgeons in the 90s that most BMS are characterised by a honeymoon period of rapid weight loss during the first year that may or may not be maintained thereafter. We needed more than a one year follow up result in order to advocate wide use of any BMS. This was due to many factors. In most bariatric programmes there is a period when the patient is being reintroduced to eating after BMS.

The patient is started on ice chips initially, then a diet of water, then clear liquids, then soups, followed by pureed food and then regular solid foods. During this re-introductory period to food which ranges from three months to one year after the different bariatric metabolic surgeries, depending on the programme, the average patient rarely consumes more than seven hundred calories of food a day.

"Those who have not learnt from or cannot remember the past are condemned to repeat it." (Philosopher George Santaya)

With such a limitation in caloric intake, most patients loose significant amount of weight rapidly. This effect is independent of the particular bariatric procedure. This effect is enhanced by four other factors:

  1. It takes time for any patient to adjust to eat small quantities as prescribed after most BMS.
  2. Patients are afraid of complications and as such are very compliant.
  3. It is also at this time when patients with BMS are most motivated. For most patients, surgery is the last-ditch effort at addressing their obesity that has been recalcitrant to nonsurgical treatment and finally
  4. This first year is the time when the patients have the most contacts with members of the bariatric surgery multi-disciplinary team (MDT). This contact with the MDT has been well documented to enhance motivation, compliance, weight loss and weight loss maintenance.

Patients regain weight after the first two years because of either the operation or patient factors. There is the loss of restrictive effects of some of the procedures. There is altered eating habits by the patients who learn to adopt and can ingest high caloric liquids. After a year, the fear to eat is gone, the patients are less compliant, their motivation is less and there is decreased contact time with the members of the MDT. Finally, the body adapts to the initial weight loss with alteration of the physiologic set point.

Based on these observations and understanding, an unwritten agreement was reached among bariatric surgeons to only publish outcomes with new procedures with at least a five-year follow up. Surgeons were admonished to use procedures with less than five years data only on investigative basis and for collecting more data. Obesity is a life long disease, and treatment should not be advocated based on short-term outcomes.

"Paradigm changing ideas are usually met with derision and the proponent the object of ridicule."(MAL Fobi)

This unwritten agreement to wait for five-year follow up data was adhered to until the introduction of the laparoscopic adjustable gastric banding and later the sleeve gastrectomy in the USA around 2000 that were popularised without five years data. See where we are now!  It is not uncommon to see publications of outcomes in either Obesity Surgery Journal or Surgery for Obesity and Related Diseases based on twelve months data.

It is apparent that many surgeons do not know or have not learnt that most bariatric operations will effect good weight loss and remission of co morbidities in the first year only to fail after two years and beyond. That is why most comparative studies based on one to two years outcome do not show significant difference. We are experiencing popularisation and acceptance of operations like SADI, SGIT, SASI, SAGI and endoscopic gastroplasty with short term results.

It is time to go back and honor the principle of waiting for outcomes after five years in order to come to any conclusion about BMS procedures. Editors and reviewers of manuscripts for publications need to take  This into account when accepting manuscripts with only one or two-year follow up data for publications.

Examples of distortions can be seen in a comparative study of two procedures with malabsorptive components. At one year there were no differences in deficiencies because during that period the body is using up existing body stores of the nutrients to maintain a normal blood level. Blood test at one year will show no difference in the deficiencies whereas blood tests three or four years later shows a significant difference. We know that the protein caloric malnutrition after one anastomosis gastric bypass or single anastomosis duodeno-ileostomy with a sleeve gastrectomy is a slow insidious process that may not be easily recognized in the first year.

"There is a tendency to reject new theories when they contradict established practice or understanding." (The Semmelweis reflex)

Unfortunately, it is easy to collect test after the first year of surgery but beyond that it is rare for patients to afford the same tests at two, three, four and more years. The limitations of reporting outcomes after one year is apparent when a review of a prospective study like the stampede study by Schauer et al that demonstrates the almost equivalency of the SG and RYGB at the first year disappears by the fifth year of follow up.

In prospective studies on diabetes remission there are a lot of reports on recurrence after three years whereas in published series with one year follow up the resolution is in the high seventies to nineties.

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