Study Suggests Gastric Bypass Surgery Generates Significant Weight Loss, Especially for Caucasian and Female Veterans
BACKGROUND:
Bariatric surgical procedures have been shown to result in dramatic weight loss, resolution of comorbidities, and improved survival. However, an ongoing point of debate is whether there is heterogeneity in the outcomes of bariatric surgery across different subpopulations of severely obese adults. U.S. Veterans represent one important population, and it is estimated that more than 165,000 Veterans who use VA healthcare have a body mass index (BMI) ≥40 (morbid obesity). Also, compared with the average bariatric surgery patient in the United States, Veterans are typically older and more likely to have multiple comorbid conditions. The purpose of this study is to describe the weight loss experience in a multicenter cohort of Veterans — and to examine the determinants of significant weight loss one year after gastric bypass surgery to elucidate subpopulations of Veterans who experience better and worse weight loss outcomes. Investigators identified 370 Veterans who had gastric bypass surgery in one of 12 VA bariatric centers in 2000-2006, and who had one or more post-operative weight measures. Bariatric patients were identified from a database of major surgical procedures performed in VAMCs and maintained by the VA Surgical Quality Improvement Program (VASQIP). In addition to weight loss, investigators examined predictor variables of gender, age, race, marital status, super obesity (BMI ≥50), American Society of Anesthesiology (ASA) physical classification status (1-4: 1=healthy, 4=severe systemic disease), smoking status at time of surgery, diabetes treatment status, and whether or not the patient underwent a laparoscopic procedure.
FINDINGS:
- Gastric bypass surgery yields significant weight loss for most patients in VAMCs, but is particularly effective for female and Caucasian patients. Average estimated weight loss was 76 pounds at 6 months and 109 pounds at one year.
- Based upon estimated individual weight trajectories, 58% of the sample had lost a significant (30% or more) amount of weight one year after surgery, and < 1% lost < 10% of their baseline weight at 1 year. Veterans were more likely to lose 30% or more of their baseline weight if they were female or Caucasian.
- A majority of Veterans in this study were male (75%), Caucasian (79%), and in ASA class 3 (82%).
LIMITATIONS:
- The size of this study cohort is relatively small.
- Weight change could only be tracked for one year.
AUTHOR/FUNDING INFORMATION:
This study was funded by HSR&D (IIR 05-201; SHP 08-137). Dr. Maciejewski also is supported by an HSR&D Research Career Scientist Award. Drs. Olsen and Maciejewski and Ms. Smith are part of HSR&D's Center for Health Services Research in Primary Care, Durham, NC. The authors would like to acknowledge the VA Surgical Quality Data Use Group (SQDUG) for its role as scientific advisors and for the critical review of data use and analysis presented in this manuscript, and PCS (SQDUG, NCP) for support of this project.
Arterburn D, Livingston E, Olsen M, Smith V, Kavee A, Kahwati L, Henderson W, and Maciejewski M. Predictors of Initial Weight Loss after Gastric Bypass Surgery in Twelve Veterans Affairs Medical Centers. Obesity Research and Clinical Practice March 12, 2012;e-pub ahead of print.
