From the Guidelines
Bariatric surgery is indicated for individuals with a body mass index (BMI) of 40 kg/m² or greater, or a BMI between 35-39.9 kg/m² with at least one obesity-related comorbidity, as well as for some patients with BMI 30-34.9 kg/m² with poorly controlled type 2 diabetes, who have been unable to achieve or maintain significant weight loss through non-surgical methods. The indications for bariatric surgery are based on the patient's BMI and the presence of obesity-related comorbidities, such as type 2 diabetes, hypertension, sleep apnea, non-alcoholic fatty liver disease, osteoarthritis, or heart disease. Candidates for bariatric surgery should have attempted structured weight loss programs without success and be psychologically stable without active substance abuse issues. They must understand the procedure, its risks, required lifestyle changes, and commit to long-term follow-up care.
Key Considerations
- The primary indication for bariatric surgery is a BMI of 40 kg/m² or greater, or a BMI between 35-39.9 kg/m² with at least one obesity-related comorbidity, as recommended by the 2023 guidelines for obesity management in adults 1.
- Some patients with BMI 30-34.9 kg/m² with poorly controlled type 2 diabetes may also be considered for certain bariatric procedures, as suggested by the 2014 guidelines for the management of overweight and obesity in adults 1.
- Bariatric surgery should be considered an adjunct to lifestyle treatment, including behavioral treatment, appropriate dietary modification, and physical activity, as emphasized by the 2014 guidelines for the management of overweight and obesity in adults 1.
- The decision to proceed with bariatric surgery should be based on multiple factors, including patient motivation, treatment adherence, operative risk, and optimization of comorbid conditions, as recommended by the 2023 guidelines for obesity management in adults 1.
Benefits and Risks
- Bariatric surgery can lead to significant and sustained weight loss, as well as improvements in or resolution of obesity-related comorbidities, such as type 2 diabetes, hypertension, and sleep apnea, as reported by the 2024 guidelines for adult overweight and obesity management 1.
- The surgery works through restriction, malabsorption, or hormonal changes affecting hunger and satiety, and can significantly improve or resolve obesity-related health conditions and reduce mortality risk in appropriate candidates, as explained by the 2019 systematic overview of international evidence-based guidelines for obesity management 1.
- However, bariatric surgery also carries potential risks and complications, including surgical complications, nutritional deficiencies, and the need for long-term follow-up care, as highlighted by the 2017 white paper on obesity and weight management 1.
Long-term Follow-up Care
- Long-term follow-up care is required for at least 2 years and sometimes for the remainder of the patient's life, with regular appointments with a physician familiar with the treatment of obesity and bariatric surgery, as recommended by the 2019 systematic overview of international evidence-based guidelines for obesity management 1.
- The frequency of care appointments depends on the type of surgical procedure and the severity of weight-related complications and other comorbidities, as emphasized by the 2017 white paper on obesity and weight management 1.
From the Research
Indications for Bariatric Surgery
The indications for bariatric surgery include:
- Severe obesity, defined as a body mass index (BMI) of 40 or higher, or a BMI of 35 or higher with serious obesity-related comorbidities, such as type 2 diabetes, hypertension, dyslipidemia, and sleep apnea 2, 3, 4, 5
- Obesity-related comorbidities, such as:
- Failure of non-surgical weight loss attempts, such as diet, exercise, and behavioral therapy 6, 5
- BMI of 30-35 with inadequately controlled hyperglycemia despite optimal medical treatment for type 2 diabetes 2
Patient Selection Criteria
Patient selection for bariatric surgery should consider:
- Age: 19-64 years old, with more severe comorbidities considered for adolescents and elderly patients 4
- Comorbidity severity: more severe comorbidities, such as diabetes and hypertension, considered for surgery 4
- BMI: 40 or higher, or 35 or higher with serious obesity-related comorbidities 2, 3, 4, 5
Surgical Procedures
Common bariatric surgical procedures include: