A technique already used in the emergency room may have new potential as a minimally invasive treatment for morbid obesity, preliminary findings suggest.
The procedure, called gastric artery embolisation, is usually employed as a nonsurgical way of stemming blood loss by blocking (embolising) a principle blood pathway.
Significant weight loss
Doctors inject microscopic beads into the bloodstream. Normal blood flow then carries them into the arterial region, where blockage occurs.
The technique is not approved for weight loss. But under an "investigational device exemption", the U.S. Food and Drug Administration granted permission for a five-patient pilot study to see if the procedure could curtail blood flow to the stomach and thereby suppress production of the "hunger hormone" ghrelin.
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Elevated levels of ghrelin can keep people from sticking with a diet, the researchers explained.
By blocking ghrelin production, the researchers hope that a resulting loss of appetite will translate into significant weight loss for patients 100 pounds or more above their ideal body weight, or with a body mass index (BMI) of 40 or more.
BMI is a calculation of body fat based on height and weight, and a BMI of 40 is considered morbidly obese.
"It seems promising, and we think there is huge potential," said study lead author Dr Mubin Syed, an interventional radiologist with Dayton Interventional Radiology in Dayton, Ohio.
However, it's still too early to know how well this experimental approach to weight loss will work, Syed added.
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"For now, bariatric [weight-loss] surgery is still the standard treatment approach for obese patients for whom diet and exercise alone is not enough," Syed said.
Syed and his colleagues were scheduled to present their findings in Chicago at the annual meeting of the Radiological Society of North America.
More than one-third of U.S. adults are obese, according to the U.S. Centres for Disease Control and Prevention. This puts them at risk of other serious conditions such as type 2 diabetes and heart disease.
Although gastric bypass surgery has a reliable track-record, Syed said there is a need for a nonsurgical alternative given that there's always some risk for complications with invasive surgery.
"Problems occur in about 10 percent of cases, and so some patients are reluctant to have the [weight-loss] surgery, even when nothing else has worked," he said.
Having read of attempts to suppress ghrelin in animals and people, Syed and his colleagues set out to attempt weight loss through gastric embolisation.
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The four patients enlisted so far had a BMI of 40 and above. The fifth patient hasn't been selected yet, the study authors added.
In ER patients, the one-hour bead injection process involves threading a catheter through a patient's groin. But in a first, Syed and his team chose to thread the catheter through the radial artery of each patient's wrist. This entry point is considered safer and more convenient for obese patients, they said.
The results have been mixed. One patient lost 50 pounds within nine months of the procedure, while two patients experienced more "mild" weight loss, the researchers said. A fourth patient, who also has diabetes, had safely lost 26 pounds three months out.
Still, Syed cautioned that the technique may not be appropriate for all candidates.
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"Patients with a history of depression tend to eat even when they're not hungry, so this procedure would not be for them," he said. "It would also not be for people who have arterial disease, or have previously had a bypass operation."
Dr John Morton, chief of bariatric and minimally invasive surgery at Stanford University School of Medicine, said the approach has "intuitive appeal and seems to make sense".
Given the extent of the nation's obesity crisis, "clearly we need to come up with more options", said Morton, who wasn't involved with the study.
"But while it's intriguing, it's a small study," Morton added. "And a lot of work still needs to be done to see just how effective it is."
Data and conclusions presented at meetings have not gone through the rigorous peer review required before publication in a medical journal.
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