Neurologists test brain implant to tackle drug addiction
The summer solstice ushered in a sunny new era in the life of a former heroin addict surnamed Chen.
“For the first time in more than 10 years, I can live like a normal man,” he said.
Chen underwent surgery at Ruijin Hospital on June 21 to remove a pacemaker-like device that was implanted in his brain in 2017. The device was then turned off over the past six months. During that time, Chen didn’t return to drugs. Doctors said that meant the treatment was successful in curing his addiction.
Chen lies waiting for the DBS device to be removed on June 21.
Is this the new frontier of treating drug addicts? It’s a timely question as the world observes the International Day Against Drug Abuse and Illicit Trafficking on Wednesday.
Ruijin Hospital is conducting clinical trials on applying the neurological technique called deep brain stimulation (DBS) to drug addiction. The technique, which involves the insertion of electrodes into targeted areas of the brain, has long been used to treat Parkinson’s disease and obsessive-compulsive disorder.
Hospital officials said DBS could counter the body’s craving for drugs such as methamphetamine, heroin and methadone.
“There is a reward system in the brain triggered by our neural circuit and nucleus,” said Zhang Chencheng, a doctor at the hospital. “Drugs stimulate the system, and the neural circuit sends out signals of fleeting pleasure.”
DBS, he said, directly stimulates the nucleus and create the sensation of pleasure, but with passing time, the patient will no longer feel the pleasure and the body will cease craving drugs.
Sun Bomin, director of Ruijin Hospital’s functional neurosurgery department and leader of the trials, told Shanghai Daily that DBS has proven safe in treating obsessive-compulsive disorder.
“Addiction works on the brain in a similar way,” he explained. “Patients repeatedly do things they actually don’t want to do.”
Sun’s team will monitor the condition of the drug patients for at least a year before they turn the “pacemaker” off. If a patient is able to steer clear of drugs for at least six months after that, the trial is considered a success.
Before being accepted for treatment, patients have to undergo thorough assessments that include family background and personality.
Chen underwent surgical implantation of the DBS device in April 2017, after an unsuccessful 10-year battle to kick his heroin habit.
He was born and raised in Hainan, the island province of southernmost China. Drug use in his hometown of Danzhou was particularly rife, he said.
“So many people were using heroin without knowing what it really was,” he said. “It was the fashionable thing to do.”
Chen said he can’t now recall when he actually became addicted to heroin, but by that time, it was too late.
“The first thing I thought of after waking up every day was heroin,” Chen said. “When the drugs ran out, I would do anything to buy more.”
He tried a rehabilitation center. He tried locking himself up in the room. Nothing worked.
Heroin cost Chen everything: money, job, health and self-esteem.
“I struggled every day with guilt and remorse,” said Chen. “I guess I’m just weak.”
Chen has seven brothers and sisters. No matter how many times he failed to give up drugs, they never gave up on him.
When a local doctor who had been on an exchange program with Ruijin Hospital told Chen about the DBS treatment, his siblings decided to grab what they thought was the last straw. They all pitched in to pay for his flight to Shanghai.
Chen said the effects were immediate after doctors switched on the pacemaker.
“As soon as they turned the machine on, I felt happy as I have never felt before,” he recalled.
Days after the surgery, he returned to Hainan. The first thing he did was buy some heroin.
“I wanted to make sure I didn’t want it anymore,” he explained. “I threw it away immediately, and knowing that I had rejected it made me cry.”
Half a year ago, the doctors remotely turned the machine off without telling Chen. He didn’t return to drugs.
Chen now runs some small businesses with friends and is planning to get married.
Dr Sun Bomin, director of Ruijin Hospital’s functional neurosurgery department and leader of the trials, is in surgery. His team has been treating Parkinson’s disease and obsessive-compulsive disorder with DBS for years. In recent years, he has moved focus to drug addiction.
While there are precedent cases of using DBS to treat methamphetamine and heroin addiction in Europe and the U.S, Ruijin Hospital is believed to be the first in the world to use DBS to try and cure methadone addiction.
Methadone is a drug used in China and many countries around the world to replace heroin in rehabilitation programs for addicts who want to come clean. There are 13 methadone clinics in Shanghai offering the drug for free to addicts on a controlled basis. Such treatment allows authorities to keep tabs on addicts and releases addicts from the necessity of turning to crime to finance their habits.
The problem is that methadone itself is addictive and its withdrawal symptoms are more excruciating than those for heroin.
A man named Fang, who can’t survive without a dose of methadone every day, is the latest patient of the DBS project.
Fang underwent DBS surgery a month ago. He told Shanghai Daily that he didn’t know what he was getting into when he went into a methadone-treatment program.
His road to addiction started somewhat innocently. Fang said he used to drink a lot with business clients, which caused him diarrhea problems.
Fang resorted to diphenoxylate, a pharmaceutical opioid, to treat his diarrhea but ended up becoming addicted to the drug.
“Ten years ago, a friend of mine told me that methadone could help get me off diphenoxylate,” said Fang. “I should never have listened to him.”
Fang managed to get onto a methadone program by swapping his clinical urine sample with another man who was a heroin user. That’s when a new nightmare began.
“Imagine if you want to travel with your family or you are invited on a business trip out of town,” he said. “You can’t do either because you have to go to the clinic every day to drink your dose of methadone.”
Whenever Fang tried to kick methadone, he became aggressive, smashing things at home or becoming violent toward his wife.
Li Jun, a doctor from Ruijin Hospital who is in charge of Fang’s case, said it was a miracle that Fang survived as long as he did.
After the surgery, Fang’s condition has improved. His daily doses of methadone have been greatly reduced.
“Give it another half year, and I’ll be clean,” he said.
Despite some initial successes with DBS treatment, doctors at Ruijin Hospital said it’s hard to find patients. The trial project was designed for 20 patients, but after two years, only seven people have participated.
“Many just can’t make up their minds,” trial leader Sun said. “Others failed personality tests.”
Drug addicts may have grounds for some concern. The effects of DBS on the brain aren’t fully understood yet. In the US, at least two projects that tried to treat alcoholism with DBS were dropped when they couldn’t justify associated risks, according to The Associated Press.
“It would be fantastic if there were something where we could flip a switch, but it’s probably fanciful at this stage,” Adrian Carter, head of neuroscience at Monash University in Melbourne, told AP about applying DBS to drug addiction.
Last year, Sun’s team published a paper about the death of a patient from a drug overdose three months after DBS surgery.
