Efficacy and safety comparison of single anastomosis sleeve ileal bypass versus one anastomosis gastric bypass: a systematic review and meta-analysis.

Background: Obesity and its associated medical problems are a global health concern. Combining metabolic and restrictive approaches may yield better results, as seen in one anastomosis gastric bypass (OAGB) and single anastomosis sleeve ileal (SASI) bypass, which evolved from Santoro's technique.

Objectives: To compare the efficacy and safety of SASI bypass versus OAGB, focusing on weight loss, comorbidity remission, nutritional outcomes, and complications.

Setting: A systematic review and meta-analysis of published observational studies.

Methods: A literature search across PubMed, Scopus, Embase, and Cochrane databases identified 234 articles, with eight meeting inclusion criteria. Primary outcomes included obesity-related medical problem remission. Secondary outcomes assessed weight loss, complications, albumin, vitamin B12, and vitamin D levels.

Results: A total of 232 SASI and 313 OAGB patients were included, with follow-ups from 6 to 60 months. Body mass index change was not statistically different (-.64, 95% confidence interval {CI} [-3.37; 2.10]). Percent total weight loss favored SASI (mean difference [MD] 3.87, 95% CI [.96; 6.78], P < .05). Obesity-related medical problem remission rates were similar, including type 2 diabetes (odds ratio [OR] .99, 95% CI [.25-3.94]), hypertension (OR .53, 95% CI [.19-1.45]), dyslipidemia (OR 1.05, 95% CI [.39-2.81]), and obstructive sleep apnea (OR 3.46, 95% CI [.49-24.20]). SASI had higher vitamin B12 levels (MD 99.78, 95% CI [26.61; 172.95], P < .01), while vitamin D and albumin levels were similar. Complications were higher in SASI (OR 2.57, 95% CI [1.34; 4.92], P = .004), mainly Clavien-Dindo I-II.

Conclusion: Both OAGB and SASI yield high remission rates and sustained weight loss. SASI had slightly lower vitamin deficiencies but higher mild-to-moderate complications.