Millions of people around the world are struggling with alcohol addiction, but only a small fraction stop drinking or seek treatment for their addiction. That's because once alcohol hooks you in, it becomes extremely difficult to break free. To make matters even worse, even existing therapies are rather ineffective and bear a high rate of noncompliance -- thus, an innovative type of treatment could one day go a long way towards dealing with this issue. Writing in the journal Neurosurgical Focus, researchers at Stanford report that deep brain stimulation (DBS) -- essentially, driving a mild electrical current through the brain -- could treat even the most severe alcoholics.
Alcohol stimulates the release of dopamine, the 'feel good' neurotransmitter that is usually released during pleasurable or rewarding activities. When the brain's reward center is overly stimulated with alcohol, a person learns to associate the psychoactive substance with positive experiences. In time, if a person drinks frequently and heavily, the brain becomes sensitized to the release of dopamine, so the enjoyment of alcohol fades. The immediate consequence is that a person needs to drink more and more in order to get the same 'kick'.
The transition towards addiction happens when the brain becomes so used to alcohol that it compensates for the substance's depressant effects by increasing the activity of glutamate -- the most important transmitter for normal brain function. Glumate is one of the main excitatory neurochemicals in the brain, which means alcohol will make a person more excited in the presence of alcohol -- and the brain can remain in this excited state even when alcohol is absent. Ironically, a person who is hooked on alcohol -- typically a depressant -- needs to drink more to be less excited and feel 'normal'.
The longer a person has been drinking, the harder it becomes to break the habit. That's because consistent alcohol consumption rewires the brain, forcing the alcoholic into a dreadful state when there is no more alcohol in the system. Alcohol sensitizes certain brain circuits and changes neurotransmitter levels, and it can also affect executive function, which is the part of the brain involved in decision-making that tells a person not to drink.
The effects of alcoholism on a person's life can be devastating and, in the United States alone, the addiction is responsible for a quarter trillion dollars in health care costs per year. In 2013, 45.8 percent of liver disease deaths among Americans ages 12 and older involved alcohol.
There are various types of modern alcohol rehab treatments, but recovery rates are generally very low. Addiction recovery rates for popular 12 Step groups such as AA may be as low as 5-10%, according to Dr. Lance Dodes, the author of The Sober Truth: Debunking the Bad Science Behind 12-Step Programs and the Rehab Industry. What's more, up to 75% of treated alcoholics relapse within 3 years.
According to a recent review of both animal and human studies, deep brain stimulation may be a far better option for treating alcohol use disorder. This type of therapy is widely used to treat Parkin's disease and obsessive-compulsive disorder, but scientists have noticed that it can also reduce alcohol cravings.
“DBS is a minimally-invasive brain surgery,” explained senior author Casey Halpern, MD, an assistant professor of neurosurgery at Stanford. “For Parkinson’s, we place deep brain stimulators to restore normal function of the region in the brain known to be dysfunctional. Patients improve immediately when a small dose of current is delivered to this area. We anticipate a similar treatment will be possible for alcoholism. At the moment, we’re performing animal studies to optimize this potential therapy and to learn its underlying mechanism of action.”
When they're intending to treat alcohol use disorders, researchers target the nucleus accumbens, a brain region that plays a key role in reward circuitry. Stimulating this region is linked with reduced impulsive behavior.
“The nucleus accumbens is triggered when patients anticipate a reward or prior to completing a rewarding behavior. It's been shown to be perturbed in both addictive disorders and OCD,” said Allen Ho, MD, a Stanford neurosurgery resident working with Halpern. “By targeting this brain structure with stimulation, we hope to modulate the reward circuit in the brain to help patients resist the temptation to indulge in a binge and other addictive behaviors.”
In humans, the impact of deep brain stimulation on alcohol consumption has only been reported in a handful of patients. In one of the studies that the scientists reviewed, a 54-year-old man was struggling with severe anxiety, secondary depressive disorder, and severe alcohol dependency with daily alcohol consumption of more than 10 drinks/day. The patient had been previously hospitalized on multiple occasions for withdrawal. However, following initiation of DBS, the patient rapidly and drastically reduced his alcohol consumption, and within 1 month was consuming 1–2 drinks/day and subjectively reported having completely lost the desire to drink. The same study treated another patient, a 69-year-old man with a more than 30-year history of alcohol dependence, who drank more than 200 grams of vodka daily. He also received numerous detoxifications, withdrawal treatments, and psychopharmacological interventions that had all failed. Similar to the first patient, after DBS therapy the patient began to remarkably reduce his alcohol consumption and was completely abstinent after one year.
Treating alcohol addiction with brain surgery may sound a bit extreme but the researchers explain that the procedure is one of the safest and least invasive operations performed by neurosurgeons. Considering the devastating consequences of this type of addiction, DBS might ultimately be more than worth it.
At the moment, deep brain stimulation therapy for alcohol use disorders is not approved by the U.S. Food and Drug Administration, but that may change in the face of more positive evidence. What's more, DBS might prove effective in treating other types of addictions, such as opioid addiction, and even obesity.
