Deep brain stimulation has been used to successfully treat patients with movement disorders and psychiatric disorders, and obesity has emerged as another possible clinical application.
For many patients, obesity doesn’t just affect their lifestyle, it affects their health. Conditions related to obesity include heart disease, stroke, and diabetes. And in some cases, death.
“Their day is ruled by questions like, ‘What am I going to eat next?’” said Neurosurgeon Donald Whiting, MD, system chair, Allegheny Health Network Neuroscience Institute. “Despite trying virtually every weight loss approach, they are still hungry, they can’t lose weight, or they lose it but can’t keep it off.”
That’s why Dr. Whiting is studying whether deep brain stimulation (DBS) could be a solution for these patients. Working in the same way that a pacemaker does for the heart, the treatment sends electrical signals directly to the brain.
“The ideal candidate for this procedure is someone who has met all the criteria for gastric bypass, had surgery, but still didn’t lose enough weight,” said Dr. Whiting. “We want to target the part of the brain that controls metabolism as well as hunger and cravings so we can help people change the pattern of weight gain. In effect, their metabolic balance will be modified.”
To perform deep brain stimulation surgery for obesity, Dr. Whiting places an electrode into each side of the brain. The electrode is just deep enough to reach the lateral hypothalamus, which is responsible for feeding behavior.
“Deep brain stimulation has been hugely successful for movement disorders like Parkinson’s,” said Dr. Whiting. “The electrodes help to regulate brain activity—sort of like how a thermostat regulates a furnace—by supplying a low-level electrical current to the part of the brain that needs to be regulated.”
Initially, Dr. Whiting and his fellow surgeons found that a small area of the brain, the lateral hypothalamus, just a couple of millimeters in size, was reactive at higher frequencies than is needed to correct movement disorders. The next step was to find the right amount of electrical current.
Dr. Whiting thinks of the DBS electrodes like an old transistor-style radio. If you’re not on a station at the right frequency, you get static—or no signal at all. With that, part of their research focused on identifying which electrical settings would most likely change the metabolic rate enough to start weight loss.
“Once we found the right setting—which we found could dramatically boost metabolism—we were able to set it at that setting and let it go in the patients in our study,” said Dr. Whiting. “And some lost weight.”
The electrodes placed in the brain are on continuously, keeping that portion of the brain at a consistent set-point for weight loss. Dr. Whiting said the electrodes can be put in and removed without consequence. “The procedure is reversible and adjustable.”
Dr. Whiting and his neuroscience team have been leaders in using DBS to successfully treat patients with movement disorders, such as Parkinson’s disease, and psychiatric disorders, including obsessive-compulsive disorder. Obesity is another possible clinical application for DBS.
“We’re currently moving into the second phase of researching DBS for weight loss,” said Dr. Whiting. “We suspect everyone is born with a set point for weight, and that we think we may be resetting patients’ weight thermostats with DBS. Continuing our study will help us know if that is true, and that the associated weight loss is permanent.”
For more information, call 412-359-6200