New weight loss procedure shrinks fat: Study

Washington D.C. - Turns out, a novel interventional procedure known as left gastric artery embolisation, which is generally used to treat obesity, leads to the loss of both fat and muscle.

According to a new study, the loss of muscle mass is concerning and underscores the importance of proper nutritional counseling.

Obesity is one of the major health issues worldwide, linked with serious conditions like heart disease, cancer, and diabetes. First-line treatments such as diet and exercise often don’t work.

Currently under investigation in clinical trials, left gastric artery embolisation is a less invasive option to surgery. In the procedure, microscopic beads are injected under imaging guidance into the artery that supplies blood to the stomach.

The beads block blood flow to the stomach and reduce the production of ghrelin, a hormone that stimulates hunger. Early studies have shown that embolisation is effective in helping people lose weight, but information is lacking on how it might change a patient’s composition of muscle and fat.

“There has been lots of research focused on the efficacy of gastric artery embolisation for weight loss,” said the study’s lead author, Edwin A. Takahashi. “However, there has been no data on what is contributing to the weight loss, whether the patients are losing fat, as desired, or muscle mass, or some combination of the two.”

The researchers studied CT scans of 16 obese patients who had undergone left gastric artery embolisation to treat gastrointestinal bleeding. CT scans, when used in conjunction with special software, allowed for measurements of body composition based on the different densities of tissues like fat and muscle.

The scans were done before and approximately 1.5 months after the procedure. The results were compared to those of a control group of 16 outpatients who did not undergo left gastric artery embolisation but had CT scans at two different time periods for nonspecific abdominal pain.

After the embolisation procedure, all 16 individuals experienced significant weight loss, losing an average of 6.4 percent of their body weight over 1.5 months.

While the weight loss was not surprising to the researchers, the changes in body composition were. The skeletal muscle index, a measure of the amount of muscle that connects to the skeleton and helps move the limbs, fell by 6.8 percent. Skeletal muscle is important to health, and loss of it can impair physical function and metabolism and put a person at higher risk of injury.

“The significant decrease in the amount of skeletal muscle highlights the fact that patients who undergo this procedure are at risk for losing muscle mass and need to be managed accordingly after the procedure,” said Takahashi. “We must make sure they receive adequate nutrition to minimize the amount of muscle tissue they lose.”

The patients also lost a significant amount of body fat. The overall body fat index dropped by an average of 3.7 percent. However, much of the fat loss was subcutaneous, or the fat that lies directly under the skin.

Visceral fat, the more dangerous fat surrounding the organs and associated with serious health problems like heart disease and diabetes, did not decrease significantly over the course of follow-up.