Long-Term Outcomes of Metabolic and Bariatric Surgery: Durability of Weight Loss, Metabolic Remission, and the Changing Treatment Landscape

Obesity is a chronic, relapsing disease that leads to significant metabolic, cardiovascular, and functional consequences. Metabolic and bariatric surgery (MBS) remains the most effective evidence-based treatment for achieving substantial and lasting weight loss. Additionally, the emergence of incretin-based pharmacotherapy has transformed the long-term treatment landscape. Long-term studies demonstrate that MBS results in sustained weight reduction, durable improvements in type 2 diabetes, hypertension, and dyslipidemia, as well as lower risks of cardiovascular morbidity and all-cause mortality when compared to conventional care. However, long-term outcomes and risk profiles vary among different surgical procedures. Roux-en-Y gastric bypass typically yields better long-term metabolic and weight outcomes than older restrictive procedures and, in certain cases, sleeve gastrectomy. While sleeve gastrectomy is effective, it raises concerns about reflux-related complications over time. More malabsorptive procedures, such as the duodenal switch, may achieve greater weight loss in patients with severe obesity but come with a higher nutritional burden and late adverse events. Overall, current evidence supports MBS as a treatment that modifies the disease rather than simply a weight-loss procedure. Its long-term value should be evaluated not only by changes in weight but also by the durability of metabolic improvements, procedure-specific trade-offs, and the quality of lifelong multidisciplinary follow-up. In current practice, incretin-based pharmacotherapy should be considered as an alternative, adjunct, or sequential strategy in conjunction with MBS.