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Updated: Jul 19, 2026
Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Predictors of weight status following laparoscopic gastric bypass
Yunsheng Ma1, Sherry L Pagoto, Barbara C Olendzki
1Division of Preventive and Behavioral Medicine, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA. Yunsheng.Ma@umassmed.edu
Background:
Weight loss after bariatric surgery varies and depends on many factors, such as time elapsed since surgery, baseline weight, and co-morbidities.
Methods:
We analyzed weight data from 494 patients who underwent laparoscopic Roux-en-Y gastric bypass (RYGBP) by one surgeon at an academic institution between June 1999 and December 2004. Linear regression was used to identify factors in predicting % excess weight loss (%EWL) at 1 year.
Results:
Mean patient age at time of surgery was 44 +/- 9.6 (SD), and the majority were female (83.8%). The baseline prevalence of co-morbidities included 24% for diabetes, 42% for hypertension, and 15% for hypercholesterolemia. Baseline BMI was 51.5 +/- 8.5 kg/m(2). Mean length of hospital stay was 3.8 +/- 4.6 days. Mortality rate was 0.6%. Follow-up weight data were available for 90% of patients at 6 months after RYGBP, 90% at 1 year, and 51% at 2 years. Mean %EWL at 1 year was 65 +/- 15.2%. The success rate (> or = 50 %EWL) at 1 year was 85%. Younger age and lower baseline weight predicted greater weight loss. Males lost more weight than females. Diabetes was associated with a lower %EWL. Depression did not significantly predict %EWL.
Conclusion:
The study demonstrated a 65 %EWL and 85% success rate at 1 year in our bariatric surgery program. Our finding that most pre-surgery co-morbidities and depression did not predict weight loss may have implications for pre-surgery screening.
