Bridging interventions before bariatric surgery in patients with BMI ≥ 50 kg/m2: a systematic review and meta-analysis

Background Bariatric surgery on patients with body mass index (BMI) >= 50 kg/m(2), historically known as superobesity, is technically challenging and carries a higher risk of complications. Bridging interventions have been introduced for weight loss before bariatric surgery in this population. This systematic review and meta-analysis aims to assess the efficacy and safety of bridging interventions before bariatric surgery in patients with BMI >= 50 kg/m(2). Methods MEDLINE, EMBASE, Web of Science, and Scopus were searched from database inception to September 2018. Studies were eligible for inclusion if they conducted any bridging intervention for weight loss in patients with BMI greater than 50 kg/m(2) prior to bariatric surgery. Primary outcome was the change in BMI before and after bridging intervention. Secondary outcomes included comorbidity status after bridging interventions and resulting complications. Pooled mean differences (MD) were calculated using random effects meta-analysis. Results 13 studies including 550 patients met inclusion criteria (mean baseline BMI of 61.26 kg/m(2)). Bridging interventions included first-step laparoscopic sleeve gastrectomy (LSG), intragastric balloon (IGB), and liquid low-calorie diet program (LLCD). There was a reduction of BMI by 12.8 kg/m(2) after a bridging intervention (MD 12.8, 95% CI 9.49-16.1, P < 0.0001). Specifically, LSG demonstrated a BMI reduction of 15.2 kg/m(2) (95% CI 12.9-17.5, P < 0.0001) and preoperative LLCD by 9.8 kg/m(2) (95% CI 9.82-15.4, P = 0.0006). IGB did not demonstrate significant weight loss prior to bariatric surgery. There was remission or improvement of type 2 diabetes, hypertension, and sleep apnea in 62.8%, 74.6%, and 74.6% of patients, respectively. Conclusions First-step LSG and LLCD are both safe and appropriate bridging interventions which can allow for effective weight loss prior to bariatric surgery in patients with BMI greater than 50 kg/m(2).