Key Time Points After Bariatric Surgery, From Weight Loss To Weight Regain: Long-Term Retrospective Cohort Study

Abstract

Background and Objective: Bariatric surgery may lead to an unsuccessful weight loss, weight loss plateau, and even weight regain in different time points after various types of surgery. Despite the numerous studies investigated bariatric surgery-induced weight loss, the long-term results of surgery, after repetitive weight fluctuations, is not really clear and remains as one of the most important concerns. The aim of the present study was to determine the key time points of weight changes after three types of bariatric surgery, and the estimation of five-year weight loss after surgery. Setting: This is a retrospective cohort study including patients with morbid obesity conducted in the obesity clinic of Minimally Invasive Surgery Research Center of Iran University of Medical Sciences. Methods The subjects underwent one of the three types of bariatric surgeries including laparoscopic sleeve gastrectomy (LSG), Roux-en-Y gastric bypass (RYGB), and one anastomosis gastric bypass (OAGB) which had been followed up to five years after surgery. The percentage lost to follow-up was 34% until five-year after surgery. Results The mean %EWL a total of 2567 morbid obese participants (mean age=39.03, mean BMI=45.67) in the first six months after surgery was independent of the type of surgery. Ninth and 24th month after surgery were the times that OAGB and then RYGB induced weight loss sped up rather than LSG, respectively. Weight plateau and weight regain were initiated earlier (at 18th month) and more (18.23% of maximum EWL %) in LSG in the period of five years. The %EWL in time intervals of 3-6, 6-9, and 9-12 months after LSG, RYGB, and OAGB, respectively; could estimate the long-term five years %EWL after surgery. Conclusion OAGB provides the fastest and highest %EWL, and LSG induced the earliest and most weight plateau and weight regain during five years interval post-surgery. The pattern of early weight loss could predict the long-term outcome of bariatric surgery. So early identification of suboptimal weight loss could allow consideration of earlier postoperative intervention to enhance long-term weight loss.