Background: Despite accumulating evidence of the important health benefits of bariatric surgery in morbidly obese patients in general, bariatric surgery outcomes are less clear in higher-risk, high-priority populations of patients with BMI ≥ 50 kg/m2. To help the Department of Veterans Affairs (VA) Health Services Research & Development Service (HSR&D) develop a research agenda, we conducted a rapid evidence review to better understand bariatric surgery outcomes in adults with BMI ≥ 50 kg/m2.
Methods: We searched MEDLINE®, the Cochrane Database of Systematic Reviews, the Cochrane Central Registry of Controlled Trials, and ClinicalTrials.gov through June 2016. We included trials and observational studies. We used pre-specified criteria to select studies, abstract data, and rate internal validity and strength of the evidence (PROSPERO registration number CRD42015025348). All decisions were completed by one reviewer and checked by another.
Results: Among 1892 citations, we included 23 studies in this rapid review. Compared with usual care, one large retrospective VA study provided limited evidence that bariatric surgery can lead to increased mortality in the first year, but decreased mortality long-term among super obese veterans. Studies that compared different bariatric surgical approaches suggested some differences in weight loss and complications. Laparoscopic gastric bypass generally resulted in greater short-term proportion of excess weight loss than did other procedures. Duodenal switch led to greater long-term weight loss than did gastric bypass, but with more complications.
Conclusions: The published literature that separates the super obese is insufficient for determining the precise balance of benefits and harms of bariatric surgery in this high-risk subgroup. Future studies should evaluate a more complete set of key outcomes with longer follow-up in larger samples of more broadly representative adults.
Keywords: bariatric surgery; super obese; systematic review.