Bariatric surgery often results in substantial and long-term weight loss for many patients struggling with obesity. However, a significant number of patients experience weight regain or inadequate weight loss after the procedure. While several studies have explored the use of anti-obesity medications (AOMs) to address these issues, a consensus on their effectiveness remains elusive due to variations in study populations and methodologies. Despite this, existing evidence suggests that medications such as liraglutide, topiramate, and phentermine/topiramate can be beneficial in managing post-surgical weight gain. Additionally, new anti-obesity medications hold promise for enhancing weight control following bariatric surgery.
Introduction
Bariatric surgery has proven effective in achieving significant weight loss for individuals with obesity. The sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are among the most commonly performed procedures in the U.S., accounting for 61.4% and 17.0% of surgeries, respectively, with revisions being the third most common at 16.7% (1). However, defining and measuring post-surgical weight regain and inadequate weight loss varies in the literature, complicating comparisons across studies. Nevertheless, the available data provides valuable insights into managing weight regain after surgery.
Research has documented the extent, timing, and persistence of weight loss following bariatric procedures. For instance, the Longitudinal Assessment of Bariatric Surgery (LABS) study, involving 1,406 RYGB patients followed for over five years, found that weight regain could begin as early as one year post-surgery. Patients, on average, regained 26.8% of their maximum weight loss by five years (2). Similarly, the Swedish Obese Subjects (SOS) study compared 2,010 individuals who underwent bariatric surgery with matched controls, showing that weight regain typically starts around 1-2 years post-surgery and stabilizes around 8-10 years. Weight regain ranged from 8-13% following gastric banding, vertical banded gastroplasty (VBG), and RYGB before plateauing (3, 4). Another extensive study by Baig et al., which analyzed 9,617 patients from India, indicated that weight regain after five years varied from 6-22% depending on the type of surgery (5). The frequency of weight regain ranged from 15.9% to 35.1% for SG, 5% to 14.6% for RYGB, and 1% to 3% for one-anastomosis gastric bypass (OAGB), depending on the definition of weight regain used.
These studies underline that weight regain after bariatric surgery is a common issue, with varying degrees of severity influenced by the type of surgery. This regain can lead to a range of health issues, including diabetes, hypertension, and cardiovascular disease (6). Thus, it is crucial for healthcare providers to offer effective strategies for managing post-surgical weight regain, including pharmacologic interventions.
Pharmacologic Management for Weight Optimization
Pharmacologic management is recommended for individuals with a body mass index (BMI) of 30 kg/m² or higher, or a BMI of 27 kg/m² with comorbidities (7). Medications can aid in weight management by targeting different physiological mechanisms that contribute to obesity (8). Currently, five medications are FDA-approved for long-term weight management: orlistat, phentermine/topiramate, liraglutide 3.0 mg, naltrexone/bupropion, and semaglutide 2.4 mg. Additionally, some drugs are used off-label for weight management, including phentermine (beyond three months), topiramate, liraglutide 1.8 mg, naltrexone, bupropion, semaglutide 2.0 mg, and tirzepatide. The effectiveness of these medications in managing weight regain after bariatric surgery remains an area of active research.
Conclusion
Addressing weight regain following bariatric surgery requires a multifaceted approach, with pharmacologic management being a key component. Although current evidence highlights the potential benefits of medications like liraglutide, topiramate, and phentermine/topiramate, further research is needed to refine treatment strategies and improve outcomes. As new anti-obesity medications become available, they may offer additional options for optimizing weight management after bariatric surgery, potentially leading to more effective long-term weight control and improved patient health.
