Psychotherapeutic interventions for cannabis abuse

Jul 21 2006

Marijuana dependence and abuse can be moderately improved by various psychotherapy treatments - but reduced use rather than abstinence may be the best clinicians can hope for at this time, a new review finds.

One-on-one cognitive behavioral therapy (CBT) is most effective, but other counseling approaches also help users to cut down or improve social problems associated with their marijuana use.

Dr. Marc Auriacombe of the Addiction Research Group at the Université Victor Segalen in Bordeaux, France, and colleagues analyzed results from studies of 1,267 people who received no or delayed intervention, motivational enhancement therapy (MET), family therapy, CBT or combinations of these for marijuana abuse or dependence.

The researchers measured outcomes such as abstinence from marijuana (cannabis) use, improvements in family and social problems, other drug abuse and continuing treatment to assess the various approaches.

"The six studies included in this review show that cannabis dependence is not easily treated by psychotherapies in outpatient settings," the authors write. "Cognitive-behavioral therapy both in individual or group sessions and motivational enhancement in individual sessions has been demonstrated to be effective to reduce cannabis use."

The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

Because the researchers compared studies with varied interventions and timelines, they didn't perform a meta-analysis that measured the overall results, and so did not provide overall comparisons across studies. But they found improvements in different measures of patients who received some type of psychotherapeutic interventions, especially CBT. Among these:

• In the study of 450 users that showed the greatest benefit of CBT, marijuana use was lower for those who received sessions of CBT or MET, and at four months, 22.4 percent of those in one-on-one CBT intervention had been abstinent for the previous 90 days compared with 8.6 percent of those treated with MET.
• Another study of 212 users showed those who received CBT or social support had a reduction in marijuana use throughout the post-treatment follow-up period and at 12 months; about 14 percent reported abstinence from marijuana use and 19 percent reported use at 50 percent or less of their pretreatment levels.
• A smaller CBT-MET study rewarded users for staying clean. Some of the 60 participants received vouchers exchangeable for retail items contingent on them submitting negative urine specimens. However, results showed no clear benefit with either treatment, although participants who received vouchers were more abstinent than those who did not.

CBT emphasizes the role of how people think, rather than external influences, in causing negative feelings and behavior, and encourage patients to make positive changes. MET seeks to enhance motivation for behavior change by working with and resolving ambivalence, while family therapy focuses on changing the interaction patterns within a patient's entire family.

New drug therapies may be needed to help abusers when psychotherapy fails, according Auriacombe.

"The high relapse rate and number of cannabis dependent individuals suggests the importance of developing pharmacotherapies for patients who may be less responsive to other treatments," Auriacombe said. "In general, the problem in treating cannabis-dependent individuals has been less that of treating and more of preventing relapse."

In terms of the improving low abstinence rates, Auriacombe said, "Alcohol research has suggested that the therapeutic effects of pharmacotherapy and psychotherapy may be synergetic, with the greatest treatment efficacy seen when medications are combined with psychotherapy." He said that similar combinations "may prove optimal in the treatment of cannabis dependence."

People often fail to notice that a friend or neighbor has a marijuana problem because the consequences of cannabis use are less striking than those associated with other drugs, according to Dr. Alan J. Budney of the University of Vermont's Treatment Research Center. "You don't see the severe acute consequences you get with alcohol or cocaine," Budney said.

According to the United Nations Office on Drugs and Crime, marijuana is the most widely abused drug in the world.

By Lise Millay Stevens