Weight Loss Speed and Early Predictors to Success After Bariatric Surgery

Background: Despite marked weight loss after bariatric surgery (BS), there is a subset of patients who fails to achieve a successful weight loss or experiences long-term weight regain. Defining the early factors linked to BS unsuccess is mandatory to promote prompt intervention to optimize weight loss (WL). Controversial data are available about predictors of success. We aimed to retrospectively assess whether clinical baseline characteristics of patients submitted to BS, the speed of weight loss (WLspeed), or early predictors factors were associated with successful WL after 5 years of follow-up. Methods: This is a retrospective database study of a prospective cohort with a 5-year follow-up. We established the success or failure of bariatric surgery in terms of weight loss according to a selected criterion: (1) Brolin, (2) Reinhold modified by Christou, (3) Biron, (4) total weight loss (TWL) > 20%, and (5) percentage of changeable weight loss (%AWL) >35%. We analyze the WLspeed as the mean difference between body mass index (BMI) at 6 months or BMI at 12 months and the baseline BMI, and a multivariate analysis was performed. Results: In total, 223 (38.7%) patients underwent sleeve gastrectomy and 353 (61.2%) underwent laparoscopic Roux-en-Y gastric bypass (LRYGB). According to the criteria, the success rates at 5 years were: the excess weight loss (EWL) > 50% 464 (80%), Reinhold modified by Christou 436 (75.6%), Biron 530 (92%), TWL > 20% 493 (85.5%), and AWL < 35% 419 (72.7%). We found a strong correlation between the first year success and the long-term results for all the criteria included in the study. Among our patients, the better results in the long term are statistically significant younger 44 versus 47 years old ( p < 0.001) and lighter 45.4 versus 46.9 ( p < 0.05) with higher proportion of women ( p < 0.05), RYGB ( p < 0.001), and less comorbidities: hypertension, diabetes mellitus type 2, and dyslipidemia ( p < 0.05). In our series, there were a statistically significant differences in the nadirBMI 26.1 versus 31( p < 0.001) and BMI at 5 years 28.5 versus 37 ( p < 0.001). Patients who achieved or surpassed the mean WLspeed >13, 15, at 6 months or >16, 15 at 12 months were more likely to achieve success in any criteria proposed ( p < 0.001). Conclusion: In conclusion, our results demonstrate that the greater the initial weight loss after BS, the better the outcomes are. However, the speed to lose weight in the first year after surgery is not a success criterion in the long term. Patients with higher %EWL, %TWL, and %AWL at 6 months after BS might be at state of future success.