Early Improvements in Metabolic Risk Factors and Non-Alcoholic Fatty Liver Disease Following One Anastomosis Gastric Bypass Surgery: A 4-Month Prospective Study.

BACKGROUND AND AIMS: Obesity is a growing public health concern and major risk factor for conditions including non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and diabetes. This study aimed to assess the early effects of one anastomosis gastric bypass (OAGB) surgery on metabolic risk factors and liver-related parameters in patients with morbid obesity. METHODS: This prospective longitudinal study included 41 patients aged over 30 years who had a medical indication for bariatric surgery. All participants underwent one anastomosis gastric bypass (OAGB) surgery and were assessed preoperatively and 4 months postoperatively for anthropometric and biochemical parameters, liver ultrasonographic and elastographic findings, as well as visceral and subcutaneous fat distribution. RESULTS: Four months postoperatively, mean body weight and BMI decreased significantly to 90.2 ± 18.1 kg (p < 0.001) and 32.6 ± 5.5 kg/m2 (95% CI: 9.5 [8.5-10.6], p < 0.001), respectively. Glycemic indices, lipid profiles, and liver enzymes improved significantly, alongside reductions in visceral and abdominal subcutaneous fat thickness (p < 0.001). Shear wave elastography (SWE) measurements also significantly decreased (95% CI: 0.9 [0.6-1.1], p < 0.001). By follow-up, 70.7% of patients showed no ultrasonographic evidence of hepatic steatosis, reflecting a 65.8% increase in resolution compared to pre-surgical status, with 11 classified as grade 1, one as grade 2, and none as grade 3. CONCLUSION: OAGB surgery is associated with significant early improvements in obesity, NAFLD and its related metabolic risk factors in morbidly obese patients. Future studies should assess long-term outcomes to determine the sustainability of these early benefits.