Page 17 - When surgery alone won’t cut it - Valerie Maureen Monpellier

Weight loss after RYGB
Weight loss after bariatric surgery was frequently described as percentage excess weight loss (%EWL), which is calculated with the following formula 65:
%EWL = preoperative weight - current weight x 100% preoperative weight - ideal weight*
* ideal weight is defined as body weight at BMI: 25kg/m2
However, more recently, %EWL is being replaced by the percentage total weight loss (%TWL), because %TWL is less influenced by the preoperative BMI of the patient 65-67. For the calculation of %TWL the following formula is used:
%TWL = preoperative weight - current weight x 100% preoperative weight
Weight loss after RYGB shows a specific pattern. Patients lose most of their weight in the first 3-6 months, after that the weight loss gradually declines until weight is stabi- lized around 18 months after surgery 2. At 18 months after surgery there is a plateau phase 2. At this point, patients who have undergone a RYGB show a mean EWL of about 60-70% and mean TWL of about 20-30% 2,3,7,68. Like all other bariatric proce- dures, a RYGB has a significant positive effect on diabetes mellitus, hypertension, cancer incidence and cardiovascular disease 2,3,7,68. Furthermore, it seems to have a positive influence on patients’ well-being 69.
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