Troubled Past May Raise Risk for Drug Relapse

Megan Brooks

October 22, 2015

CHICAGO — A history of physical, emotional, or sexual abuse may have a direct effect on the brain that is linked to relapse, new research suggests.

On neuroimaging, cocaine-dependent adults with a history of traumatic life experiences show increased nerve cell activity in response to drug-related visual cues in brain areas associated with addiction, which may raise their risk for relapse after treatment, the researchers found.

The finding may also help explain why individuals with a history of abuse are two to three times more likely to develop a substance-abuse disorder than the general population, said lead author Paul Regier, PhD, from the Department of Psychiatry, University of Pennsylvania, Philadelphia.

"Yesterday matters," Dr Reiger said during an October 19 press briefing at the Society for Neuroscience (SfN) 2015 Annual Meeting, where he presented his research.

"The past does have long-term effects and can leave scars and what we are beginning to understand is these effects can be seen at the level of the brain. Stress and addiction can impact the brain at a very common pathway, the mesolimbic reward system," Dr Reiger said.

Target for Intervention?

Dr Reiger and his colleagues studied 25 treatment-seeking cocaine-dependent patients. Participants completed the Addiction Severity Index (ASI), which includes questions about history of emotional, physical, or sexual abuse; 11 patients had experienced some kind of abuse in their past, while 14 had no history of abuse.

After inpatient stabilization, they underwent event-related blood oxygen level–dependent functional MRI during exposure to brief evocative (cocaine, sexual, aversive) and neutral cues.

"The question is, do individuals with an abuse history process these evocative stimuli different than individuals who do not have a history of abuse, all in cocaine-dependent individuals?" Dr Reiger explained. The answer is yes.

All participants, when exposed to drug cues, had a "pretty big response in several different brain areas, including the mesolimbic pathway," Dr Reiger noted. "But what is striking is that when we break these into history of abuse or history of no abuse, the ones with a history of abuse are almost entirely carrying this signal" in the mesolimbic reward pathway.

"Because we know where it's happening in the brain we might be able to pharmacologically or behaviorally intervene and help these individuals," Dr Reiger said.

The next step is to determine how a history of abuse is associated with relapse. "Previous research in the lab has shown that this brain response is predictive of relapse, but we don't know if there is a direct connection between a history of abuse and relapse. Those are results that we will have in the very near future," Dr Reiger said.

"Stressful events can increase vulnerability to addiction," said Jakie McGinty, PhD, director of the Neuroscience Institute at the Medical University of South Carolina in Charleston, who moderated the briefing devoted to new research on how stress and addiction shape the brain.

"The National Institute on Drug Abuse estimates that one in six people that try cocaine end up with cocaine dependency. Why does that one person go on to become addicted? In many cases, previous or current stressful life events are involved," Dr McGinty commented.

She also made the point that "60% of Americans who undergo treatment for drug addiction relapse within a year." In these individuals, "heightened sensitivity in brain areas associated with addiction may be associated with increased risk of relapse," Dr McGinty said.

"Changes in brain circuitry caused by stress and other factors play an important and incredibly complex role in the development of drug addiction — and in the frustratingly difficult process of overcoming an addiction," Peter Kalivas, PhD, chair of the Department of Neuroscience at the Medical University of South Carolina, added in a conference statement. "These latest findings are deepening our understanding of the brain circuitry underlying drug addiction and suggesting new possibilities for more effective preventions and treatments."

The study was supported by the National Institute on Drug Abuse. The authors have disclosed no relevant financial relationships.

Society for Neuroscience (SfN) 2015 Annual Meeting. Abstract 315.05. Presented October 19, 2015.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: