Long-term outcomes of metabolic and bariatric surgery: a 10-year study of effectiveness and predictors.

Abstract

This study aimed to evaluate long-term effectiveness of metabolic and bariatric surgery (MBS) over a 10-year period, to identify predictors of therapeutic success and weight loss, and to compare differences between Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). A retrospective cohort study was conducted on patients who underwent MBS between 2010 and 2013 at a Portuguese tertiary hospital (n = 909). Patients who underwent laparoscopic adjustable gastric banding or revisional surgery during follow-up were excluded (n = 280). The 10-year loss to follow-up rate among included participants was 37.2% (n = 147). Clinical data were collected over a 10-year period. Therapeutic success was defined as a percentage excess weight loss (%EWL) of at least 50%. Multivariate logistic or linear regression analyses were performed to identify independent predictors of long-term outcomes. Of 395 participants included, 89.6% were females, with a mean age of 41.9 ± 10.8 years and a median body mass index (BMI) of 43.8 [40.9; 47.8]Kg/m²; 88.1% underwent RYGB. After 10.0 ± 1.30 years, the mean weight loss was 31.0 ± 14.4 kg, corresponding to a percentage of total weight loss (%TWL) of 26.4 ± 11.0% and %EWL of 61.9 ± 26.6%. Therapeutic success was achieved by 70.6% of patients, and 39.0% lost at least 30.0% of baseline weight. Eighteen patients (4.55%) lost less than 5%. RYGB was associated with higher odds of long-term therapeutic success compared to SG (OR = 2.158 [95% CI 1.083-4.303], p = 0.029). Weight loss at one year also predicted long-term success (OR = 1.111 [95% CI 1.075-1.149], p < 0.001), while a higher BMI predicted lower %EWL (β = -1.684 [95% CI: -2.366 to -1.001], p < 0.001). MBS remains an effective long-term treatment for obesity, with RYGB offering superior outcomes compared to SG in our cohort. Our findings highlight the importance of early postoperative weight loss, and baseline BMI as key predictors of long-term outcomes and success after bariatric surgery.