Comparative risk of fracture for bariatric procedures in patients with obesity: A systematic review and Bayesian network meta-analysis

Abstract

Objective: Bariatric surgery (malabsorptive [i.e., biliopancreatic diversion, BPD], restrictive [i.e., sleeve gastrectomy, SG; adjustable gastric banding, AGB] and mixed [i.e., gastric bypass, GB] procedures) has been reported to be associated with an increased risk of fracture; however, which procedure poses the greatest risk of fracture is still controversial. The aim of the current meta-analysis was to investigate the degree of fracture risk after different bariatric procedures.

Material and methods: Electronic databases, including Medline/PubMed, EMBASE and Cochrane library, were systematically searched from inception to July 11, 2019 with no language restrictions to retrieve randomized controlled trials (RCTs) or cohort studies evaluating the impact of any kind of bariatric surgery on postoperative fractures in patients with obesity. Pairwise meta-analysis and Bayesian network meta-analysis were performed to pool the outcome estimates of interest, including fracture incidence and fracture risk. The values of the surface under the cumulative ranking (SUCRA) probability for fracture risk were calculated and sorted according to the different surgical procedures.

Results: A total of twelve studies published between 2010 and 2019, comprising 159,916 participants with obesity were identified for the analysis. The incidence of fracture increased from 3% (95% confidence interval [CI] 2-4%) in patients with non-surgical intervention (drug treatment, alteration in life style and diet control) to 5% (95% CI 4-7%) in those who had undergone bariatric surgery (pooled relative risk [RR] = 1.41 95% CI: 1.22-1.63). Network meta-analysis revealed that based on the SUCRA ranking of the different surgical procedures, the malabsorptive procedure had the highest possibility of increased fracture risk in patients with obesity (74.75%), followed by the mixed procedures (73.85%), nonsurgical intervention (43.55%) and the restrictive procedure (7.85%); for different surgery types. The BPD group had the highest possibility of increased fracture risk (99.49%), followed by the GB (74.92%), nonsurgical intervention (44.49%), AGB (26.64%) and SG (4.45%) groups.

Conclusions: Significant differences exist among different bariatric surgeries impacting on fracture risk. The malabsorptive and mixed procedures, but not the restrictive procedure, increase the postoperative risk of fracture. Considering the weight-reduction effects and fracture risk, the sleeve gastrectomy procedure may be the best choice for patients with obesity, especially those who are susceptible to osteoporosis.

Keywords: Bariatric surgery; Fractures; Network meta-analysis; Obesity.