New Guidelines for Bariatric Surgery Are 'an Important Reset'

Marlene Busko 

October 21, 2022

In a new statement, two metabolic and bariatric surgery societies recommend expanding eligibility for bariatric surgery to include individuals with a body mass index (BMI) lower than the current threshold, among other updates.

The statement recommends that the threshold for metabolic and bariatric surgery should be a BMI ≥ 35 kg/m2, regardless of comorbidities.

In contrast, providers, hospitals, and insurers currently use BMI thresholds of ≥ 40 kg/m2, or ≥ 35 kg/m2 with an obesity-related comorbidity (such as hypertension or heart disease), to define patients eligible for metabolic and bariatric surgery based on criteria established in a 1991 consensus statement by the US National Institutes of Health (NIH).

A joint statement issued today by the American Society for Metabolic & Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) updates the indications for surgery to reflect the progress in the field over the past 30 years.

"In light of significant advances in the understanding of the disease of obesity, its management in general, and metabolic and bariatric surgery specifically," leaders of the ASMBS and IFSO, which represents 72 national societies, "convened to produce this joint statement on the current available scientific information on metabolic and bariatric surgery and its indications," the document authors write.

The statement was presented today at the International Congress on Obesity (ICO) 2022 in Melbourne, Australia, and simultaneously published online in the journals Surgery for Obesity and Related Diseases and Obesity Surgery.

'Long Overdue,' 'Time to Remove Barriers'

This reset in the threshold for eligibility for metabolic and bariatric surgery is long overdue, according to the presidents of the ASMBS and IFSO.  

"The 1991 NIH consensus statement on bariatric surgery served a valuable purpose for a time, but after more than three decades and hundreds of high-quality studies, including randomized clinical trials, it no longer reflects best practices and lacks relevance to today's modern-day procedures and population of patients," Teresa LaMasters, MD, president, ASMBS said in a press release.

"It's time for a change in thinking and in practice for the sake of patients. It is long overdue," she noted.

"The ASMBS/IFSO guidelines provide an important reset when it comes to the treatment of obesity," added Scott Shikora, MD, president, IFSO.  

"Insurers, policymakers, healthcare providers, and patients should pay close attention and work to remove the barriers and outdated thinking that prevent access to one of the safest, effective, and most studied operations in medicine," he observed.

The document authors explain that when the 1991 consensus statement was issued, the main bariatric procedures were vertical banded gastroplasty, which is no longer performed, and Roux-en-Y gastric bypass (RYGB), whereas sleeve gastrectomy and RYGB together now account for about 90% of all worldwide operations.

Over the past three decades, the understanding of obesity and metabolic and bariatric surgery has grown significantly based on clinical experience and research studies, and long-term research has consistently demonstrated superior weight loss with surgery compared to nonsurgery treatments.

Major New Recommendations

The following are some of the key new recommendations.

BMI ≥ 35 kg/m2: Given the presence of high-quality scientific data on safety, efficacy, and cost-effectiveness of metabolic and bariatric surgery in improving survival and quality of life in patients with BMI ≥ 35 kg/m2, surgery should be strongly recommended in these patients regardless of presence or absence of evident obesity-related comorbidities.

BMI 30-34.9 kg/m2: Metabolic and bariatric surgery should be considered for individuals with metabolic disease and a BMI of 30-34.9 kg/m2 who do not achieve substantial or durable weight loss or comorbidity improvement using nonsurgical methods.

BMI ≥ 30 kg/m2 and type 2 diabetes: Metabolic and bariatric surgery is recommended for these patients.

Lower BMI thresholds for Asian individuals: The prevalence of diabetes and cardiovascular disease is higher at a lower BMI in Asian than non-Asian individuals. In Asian individuals, a BMI ≥ 25 kg/m2 suggests clinical obesity, and those with a BMI ≥ 27.5 kg/m2 should be offered metabolic and bariatric surgery.

Appropriately selected children and adolescents: Children and adolescents with a BMI > 120% of the 95th percentile and a major comorbidity or a BMI > 140% of the 95th percentile should be considered for metabolic and bariatric surgery after evaluation by a multidisciplinary team in a specialty center.

Bridge to other treatment: Metabolic and bariatric surgery is an effective treatment of clinically severe obesity in patients who need other surgeries, such as hip or knee replacement, abdominal wall hernia repair, or organ transplantation.

Older population: There is no upper age limit for metabolic and bariatric surgery; however, older patients should be carefully assessed. Frailty, rather than age alone, is independently associated with higher rates of postoperative complications.  

ICO 2022. Presented October 21, 2022.  

Surg Obes Relat Dis. Published October 21, 2022. Full text

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