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SASI bypass and OAGB more effective than SG in the treatment of metabolic syndrome

A retrospective analysis of sleeve gastrectomy (SG), one-anastomotic gastric bypass (OAGB) and single anastomosis sleeve ileal (SASI) bypass for the treatment of metabolic syndrome has found SASI bypass and OAGB were more effective, according to researchers form The Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.



In total, the study included 324 patients - 264 in the SG group, 30 in the OAGB group and 30 in the SASI bypass group. The majority of the patients were female (224, 69.1%). The mean age, preoperative weight and BMI of patients in the SG group were 30.05 ± 8.6 years, 109.7 ± 22.8 kg, and 38.7 ± 6.2 kg/m2, respectively; 34.8 ± 5.6 years, 107.8 ± 20 kg, and 40.5 ± 4.5 kg/m2 in the OAGB, respectively and 37.59 ± 8.8 years, 106.5 ± 19 kg, and 39.2 ± 5.1 kg/m2 SASI group, respectively.


A higher proportion of patients with type 2 diabetes opted for OAGB (19, 63.3%) and SASI bypass (18, 62%) procedures vs. the SG group (108, 41.3%). The OAGB group had a higher prevalence of hypertension, with 56.6% (N=17) of patients in this group having hypertension compared to the other two groups (27.5%, n=72 and 20.7%, n=8).


The postoperative recovery of gastrointestinal-related functions revealed vomiting was significantly lower in the SASI bypass group compared to the SG and OAGB groups. However, abdominal distension and acid reflux were more prevalent in the SG group vs OAGB and SASI bypass groups. Additionally, a higher number of patients in the OAGB group reported experiencing gastric colic compared to those in the SG and SASI groups.


All the procedures resulted in significant weight loss at the 6–12-month follow-up period, as evidenced by a significant decrease in weight and BMI compared to baseline values and a significant increase in %TWL and %EBMIL. At 12-months, SASI bypass patients showed a significant decrease in weight and BMI vs SG or OAGB patients. In addition, the SASI bypass was associated with a significantly higher percentage of total weight loss (%TWL) and excess body mass index loss (%EBMIL) compared to SG and OAGB.


In the SG group, 60 (22.7%) patients were identified as having a diagnosis of metabolic syndrome based on meeting all three diagnostic criteria, excluding those who had previously been diagnosed with metabolic syndrome. Among the 108 patients with preoperative concurrent type 2 diabetes mellitus, 65 (63.9%) experienced complete remission. Out of the 72 patients with preoperative concurrent hypertension, 54 (75%) achieved complete remission. Additionally, among the 147 patients with preoperative concurrent hyperlipidaemia, 92 (62.6%) attained complete remission. Out of the 96 patients with preoperative concurrent sleep apnoea syndrome, 90 (93.8%) patients achieved complete remission after the surgical intervention.


Following the exclusion of individuals already diagnosed with MS in the OAGB group, it was found that four (13.3%) patients still met all three diagnostic criteria for MS. Among the 19 patients with preoperative concurrent type 2 diabetes, 18 (94.7%) patients achieved complete remission. In addition, 16 (84.2%) patients had a significantly improved blood pressure profile. Among the 22 patients with preoperative combined hyperlipidaemia, 17 (77.3%) patients achieved complete remission. The complete remission rate for sleep apnoea syndrome also reached 92.3%.


After excluding individuals who met the three diagnostic criteria for MS in the SASI bypass group, only 2 patients (6.6%) remained diagnosed with MS. Complete remission was achieved in 83.3% of patients with type 2 diabetes, and complete remission was achieved in 87.5% of patients with hypertension. Complete remission was achieved in 13 out of 17 patients (76.5%) with preoperative hyperlipidaemia, while the complete remission rate for sleep apnoea syndrome in this group reached 100%.


Serum albumin levels were significantly decreased after OAGB and showed a non-significant increase after SG and SASI bypass. Vitamin B12 and 25 hydroxyvitamin D levels were reduced in patients who underwent SASI bypass but remained within the normal range whereas, vitamin B12 and 25-hydroxyvitamin D remained within the normal range after SG and OAGB. Therefore, the authors said the risk of postoperative malnutrition was higher in SASI vs SG and OAGB.

The researchers acknowledge that the results of this study represent the short-term outcomes of SG, OAGB and SASI bypass in the treatment of metabolic syndrome: “However, to fully evaluate the outcomes of the study and assess the long-term complications associated with each procedure,” they conclude, “It is crucial to conduct further follow-ups over an extended period of time.”


The findings were reported in the paper, ‘Analysis of the efficacy of sleeve gastrectomy, one-anastomosis gastric bypass, and single-anastomosis sleeve ileal bypass in the treatment of metabolic syndrome’, published in Scientific Reports.


To access this paper, please click here


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