Deep Brain Stimulation Studied as Last-Ditch Obesity Treatment
No major side effects seen in 3 patients over nearly 3 years
The three patients in Whiting's study were examples of that medical need. All were severely obese and had failed to shed weight after gastric bypass surgery -- the current last-ditch treatment option.
During the study period, the patients did have some side effects from deep brain stimulation -- nausea, anxiety and feeling "too hot or flushed" -- but they were short-lived, the researchers said. And there was some evidence that the brain stimulation was having effects. In lab tests, Whiting's team found that the deep brain stimulation seemed to spur short-lived spikes in resting metabolism.
Then, after the deep brain stimulation was programmed to the settings that seemed to boost metabolism, two patients shed some pounds -- 12 percent to 16 percent of what they weighed before the DBS settings were "optimized."
"There was some weight loss, but it was transient," Whiting said. Now a key question is, what is the right setting for the deep brain stimulation to encourage lasting weight loss? Whiting said his team is continuing to follow these three patients to try to figure that out -- and to keep monitoring safety.
Although deep brain stimulation is considered a generally safe therapy for the right patients, it is a major undertaking that requires two surgeries -- one to implant electrodes in the brain and another to place the neurostimulator. The potential risks include infection, a blood clot or bleeding in the brain, or an allergic reaction to the DBS parts.
If deep brain stimulation ever does become an option for managing severe obesity, Whiting said, he would expect it only to be used when all else fails. "This would definitely be a last resort," he said.
"At first, it would absolutely be a last-ditch option," neurosurgeon Halpern said. But, he added, it's also possible that deep brain stimulation could become an add-on therapy, used after gastric bypass for some patients whose weight does not fall -- or even an alternative in certain cases where bypass surgery is too risky.
Medtronic provided the deep brain stimulation hardware for the study and funded the work. One of Whiting's co-researchers is employed by the company.