Projection of gut microbiome pre and post bariatric surgery to predict surgery outcome

Bariatric surgery is often the preferred method to resolve obesity and diabetes, with ~800,000 cases worldwide yearly and high outcome variability. The ability to predict the long-term BMI change following surgery has important implications on individuals and the health care system in general. Given the tight connection between eating habits, sugar consumption, BMI and the gut microbiome, we tested whether the microbiome before any treatment is associated with different treatment outcomes, as well as other intakes (HDL, Triglycerides, etc.). A projection of the gut microbiome composition of obese (sampled before and after bariatric surgery) and slim patients into principal components reveals 3 different microbiome profiles belonging to slim subjects, obese and obese who underwent bariatric surgery, as opposed to the current conjecture that there are only two profiles – slim and obese. The same projection allows for a prediction of BMI loss following bariatric surgery, using only the pre-surgery microbiome, which may upgrade the decision-making process of whether to undergo the procedure or not. A different projection is associated with sugar metabolism and A1C levels. These results may be translated into better clinical management of obese individuals planning to undergo metabolic surgery.