Background: Rates of weight normalization and obesity remission after Roux-en-Y gastric bypass (GB) are unknown. This study evaluated weight loss, rates of achieving body mass index (BMI) <25 or 30 kg/m2, recidivism, and predictors of success following GB.
Methods: We retrospectively studied weight and BMI at baseline, 2 and 6 months, and annually at 1-7 years in 219 patients undergoing GB at the University of Michigan from January 2008 to November 2010.
Results: Follow-up was excellent for a population traditionally associated with high attrition rates with data availability of 157/219, 145/219, 144/219, 134/219, 123/219, 82/161, and 29/64 patients at 1-7 years, respectively. Mean baseline BMI was 47.0 kg/m2. Weight normalization (BMI <25 kg/m2) occurred in 2.3-6.8% of patients. More importantly, 47% of patients achieved remission of obesity (BMI <30 kg/m2) at some time point and 24% (52/219) at the last observed time point. BMI <30 kg/m2 was associated with a lower initial BMI and follow-up for more than 2 years.
Conclusions: Rates of weight normalization are low after GB; however, a large number of patients achieved BMI <30 kg/m2. While the percent total weight loss and excess weight loss are both quite high in the entire cohort and this is likely associated with significant health benefits, our results still underscore the need to address obesity with intensive clinical attention earlier in its course.
Keywords: Bariatric surgery; Gastric bypass; Metabolism; Obesity; Weight loss; Weight normalization.