COMPLICATIONS AFTER BARIATRIC SURGERY: A SYSTEMATIC REVIEW AND META-ANALYSIS

Sunday, October 20, 2013
Key Ballroom Foyer (Hilton Baltimore)
Poster Board # P1-33
Health Services, and Policy Research (HSP)

Su-Hsin Chang, PhD1, Carolyn R.T. Stoll, MPH, MSW2, Jihyun Song, PhD3, Amanda Calhoun1, Nikki Freeman, MA1, J. Esteban Varela, MD, MPH, FACS4, Christopher J. Eagon, MD4 and Graham A. Colditz, MD, DrPH1, (1)Washington University School of Medicine, St. Louis, MO, (2)Division of Public Health Sciences, Washington University School of Medicine, St. Louis, MO, (3)Seoul National University, Seoul, South Korea, (4)Division of General Surgery, Washington University School of Medicine, St. Louis, MO

Purpose: The goal of this study is to explore surgical complications resulting from different procedures of bariatric surgery using recently published data (past 10 years) and appropriate meta-analysis techniques.

Methods: Surgeries considered were Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB), and sleeve gastrectomy (SG). Complications in our analysis included deep vein thrombosis, pulmonary embolism, stroke, myocardial infarction, pneumonia, respiratory failure, bleeding, bowel obstruction, anastomotic stenosis, stricture, anastomotic leakage, nausea/vomiting, reflux, and wound infection. Literature searches of Medline, Embase, Scopus, Current Contents, Cochrane Library, and the Clinicaltrials.gov databases between 2003 and March 2012 were performed. Articles were screened for exclusion and inclusion criteria before data extraction. Randomized controlled trials (RCTs) and observational studies were analyzed separately. Post-surgery complication rates were synthesized by random-effects (RE) meta-analyses using both Bayesian RE models and Bhaumik models due to rare adverse events in some cases. Complications reported at various time points were categorized into ≤30 days, 30 days-1 year, and >1 year.

Results: We only report the Bayesian RE means and the 95% credible intervals in brackets for RCTs. Bleeding rates were 4.6% [2.3%-8.1%], 2.9% [1.2%-5.1%], and 0.95% [0.07%-3.3%] for ≤30 days, 30 days-1 year, and >1 year, respectively. Gastroesophageal reflux (6.3% [1.8%-12.7%]) was the most commonly seen complication, followed by nausea/vomiting (5.1%, [1.8%-10.4%]). Among the procedures, AGB contributed most to the high complication rates (6.1% for reflux and 8.4% for nausea/vomiting). For pulmonary complications, respiratory failure rate was 0.9% [0.1%-3.3%] and pneumonia rate was 2.6% [1.2%-4.2%]. RYGB had the highest pneumonia rate (2.8%), followed by SG (2.2%). Incidence rate of pulmonary embolism was 0.2% [0.0%-0.8%] (RYGB (0.8%) resulting in a higher rate than AGB (0.3%)). 2.1% [0.4%-5.5%] of patients had a gastrointestinal leak after surgery. 4% of RYGB patients reported an anastomotic leak. Bowel obstruction was found in 3.1% [1.3%-5.5%] of patients, in which RYGB appeared to have the highest rate (3.3% [1.2%-6.2%]).

Conclusions: The overall complication rate after bariatric surgery is low. However, some of the complications are life threatening, and once complications occur, they not only affect post-surgery quality of life but also discount the benefits gained from weight loss. This study provides evidence suggesting that bariatric surgery is associated with non-negligible complications, which should be well communicated with patients when surgical treatment is suggested.