Obesity has been steadily increasing worldwide for at least 50 years. It directly contributes to the rising incidence of cardiovascular, musculoskeletal, and oncological diseases. Becoming one of the most concerning public health issues, obesity accounts for a majority of healthcare expenditures in Western countries, causing approximately three million deaths per year globally. While lifestyle interventions such as diet and exercise remain the foundation of weight management, only around 2% of individuals can sustain weight loss over a 12-month period.
For individuals with morbid obesity (BMI [body mass index]> 40kg/m²) or obese patients with significant comorbidities (BMI between 30–39.9kg/m²), bariatric surgery is considered the gold standard. This surgical procedure has demonstrated long-term weight loss and substantial improvements in metabolic syndrome, and overall survival. However, it is associated with a direct mortality rate of up to 2%, a high incidence of early complications including gastrointestinal fistulas, abdominal abscesses, thromboembolic events, as well as long-term nutritional deficiencies that can lead to chronic anaemia and bone fractures, among others. It is also a very expensive procedure, costing an average of US$38,000 without complications and US$64,000 with complications, which makes it almost impossible to be offered in public health systems of developed countries.
Over the past decade, we have witnessed the emergence of new drugs such as GLP-1 agonists, initially designed to treat diabetes, but now predominantly used for weight loss purposes. While they have been associated with weight loss of up to 15% within one to two years, they also come with a high incidence of adverse effects, including nausea, vomiting, diarrhoea, abdominal pain, and headache. Additionally, these drugs are costly, leading to treatment discontinuation and subsequent weight regain.
Hence, there is a need for minimally invasive, cost-effective, and long-lasting procedures for obesity treatment, and this is where bariatric artery embolization (BAE) comes into play. BAE aims to induce ischaemic changes in the gastric fundus, reducing the number of viable orexigenic cells and consequently lowering the concentration of acylated ghrelin in the bloodstream.
Ghrelin is the sole peripheral orexigenic hormone responsible for increasing appetite in the human body and is directly associated with fat accumulation and metabolic syndrome. From the first prospective clinical trial conducted in 2015 to the present, we have been able to demonstrate that BAE is a very safe procedure, with only 3% of serious adverse events and no reported deaths thus far. It consistently leads to a sustained decrease in plasma ghrelin levels of up to 32%, and a total body weight loss of approximately nine to 10% within 12 months.
Most trials conducted so far have utilized microspheres ranging between 300–500μm in size. While shallow ulcers are often observed during upper gastrointestinal endoscopy within one week post-procedure, they are mostly asymptomatic and disappear entirely within one month. In our trial titled ‘Bariatric embolization in the treatment of patients with a body mass index between 30 and 39.9kg/m2 (Obesity class I and II) and metabolic syndrome: A pilot study’, although we target multiple feeders of the gastric fundus (left gastric, short gastric, and gastroepiploic arteries) in 90% of the participants, the majority of ulcers were found in the lesser curvature, possibly due to unnoticed reflux of the embolic agent, while none were detected in the gastric fundus itself, making it a safe target for embolization.
This trial also demonstrated the direct impact of the procedure on insulin resistance, with normalisation of mean fasting blood glucose and a significant reduction in homeostatic model assessment for insulin resistance (HOMA-IR) from 7.3 to 3.7 within six months.
More robust data from randomised, prospective trials are forthcoming, which will probably establish BAE as an essential tool in the clinical management of obesity in the near future.
Rapael Braz is an interventional radiologist at the Real Medical Center (RIVOA) in Rio de Janeiro, Brazil.