Aim. To determine the long-term effectiveness of modified laparoscopic one-anastomosis gastric bypass in patients with morbid obesity.

Materials and methods. A total of 36 patients with morbid obesity who underwent a surgery from 2010 to 2019 were divided into two groups according to the surgical intervention type. Group 1 – 20 (55.6 %) patients who underwent laparoscopic one-anastomosis gastric bypass in the modification of the clinic, group 2 – 16 (44.4 %) patients who underwent the Roux-en-Y gastric bypass. The study included patients of both sexes, aged 18 to 60 years with a body mass index (BMI) of ≥40 kg/m2. Patients with severe decompensated comorbidities, oncological diseases, and contraindications to laparoscopic interventions were excluded from the study. The results were evaluated at 1, 3, and 5 years. Anthropometric parameters were monitored dynamically; quality of life was assessed according to the Short Form 36 questionnaire, esophagoduodenoscopy with chromography and biopsy were performed to detect bile reflux. Statistical data were processed using the Statistica for Windows 13.0 software package.

Results. When analyzing the findings obtained, higher rates of weight loss in kilograms and percentage of excess and total body weight reduction during the entire follow-up period (p < 0.05) have been noted in group 1 patients. At the same time, the mean BMI had a statistical difference between the groups only 5 years after the surgery (p = 0.0487). The quality of patients’ life has been found to be significantly improved in both groups compared to that in the preoperative period, but without statistical significance in the long-term follow-up period. Bile reflux occurred in only 10 % of group 1 patients during the entire follow-up period (p > 0.05) with no signs of malignancies.

Conclusions. Laparoscopic one-anastomosis gastric bypass surgery modified in the clinic results in quick weight loss and significant improvements in quality of life in morbidity obese patients within 12 months after the surgery. Furthermore, the anti-reflux mechanism we developed is effective enough to prevent bile reflux.