AMSTERDAM – A targeted cognitive-behavioral treatment program designed by German addiction specialists for cannabis use disorder promoted abstinence in 40% of subjects at 6 months, and significantly reduced global addiction severity and psychopathological symptoms.
The approach was described at the congress by Hans-Ulrich Wittchen, Ph.D., director of the Institute of Clinical Psychology and Psychotherapy at Technische Universität Dresden.
A good percentage of participants was abstinent 6 months after treatment, even when urine tests are done. “This is a remarkable finding that we did not expect at the beginning,” Dr. Wittchen said.
For many individuals, cannabis is the primary drug of abuse. Regular heavy use is associated with a substantial risk of a cannabis-dependence syndrome and when this is combined with other substance-abuse and internalizing disorders, the result is often psychosocial, cognitive, and mental health problems.
“Cannabis use is regularly associated with a wide range of psychological symptoms, and the largest group has anxiety and depression. Patients with primary CUD [cannabis-use disorder] have become the largest group in substance-abuse centers in many European countries. These individuals have different profiles and treatment needs that are not being met in the current health care system. No clear interventional strategies have been developed,” Dr. Wittchen said.
“The patients tell us they do not feel well placed, sitting next to heroin users. In fact, that's how impressionable young people learn how to use other drugs.”
CBT as the Foundation
Dr. Wittchen and his colleagues designed a treatment program (10 individual sessions of 90 minutes each) specifically related to CUD. Based on evidence that types of cognitive-behavioral therapy (CBT) can be effective (via motivational enhancement, cognitive restructuring, psychosocial problem solving), they used CBT as a foundation. Modular components include CBT, motivational enhancement, and psychosocial problem solving. Patients develop an individual change concept and set goals. There is “quit day” preparation and training in relapse prevention, cannabis refusal skills, and so forth.
A randomized, controlled trial was designed to assess the effect of the program, compared with a delayed-treatment group, which included individuals seeking help but who were asked to wait until there was availability within the program.
Two approaches were evaluated: a standardized approach and a variant tailored to the individual's specific needs that minimized components deemed unnecessary (such as less motivational work in patients who express high motivation at baseline).
Participants were aged 16-45 years with substantial current cannabis use and meeting criteria for DSM-IV CUD. They also had significant CUD-associated psychosocial problems and could have comorbid mental disorders (though no history of psychotic disorder, suicidal ideation, or phobias) as well as concomitant other drug use (though no other dependencies).
“Our entry criteria [were] meant to correspond to the most frequent and typical characteristics of this population,” he said. “And our general campaign message was for 'everyone who wants to stop, reduce, or think about his or her cannabis use.'”
The typical patient was a male who used cannabis more than 20 times per week. Seventy percent met criteria for cannabis dependence, 78% reported life-time use of other illicit drugs, and 38% had signs of dependency for those. Anxiety disorders were diagnosed in 40% and mood disorders in 38%. “We concluded that a severe chronic CUD sample of patients was included in the study,” he said.
There were 51 subjects in the standardized treatment group, 39 in the targeted standardized treatment group and 32 in the delayed-treatment group, which served as controls. Assessments were made after 3 and 6 months to test the stability of the effects. The primary outcome measure was abstinence as measured by self-report and negative urine screen, cannabis use, addiction severity total score and domains, and severity of psychopathological symptoms.
The tailored treatment was found not to be superior to the standardized treatment; therefore, these two groups were combined for the analysis.
Trial Showed Robust Effect
At the end of treatment, approximately 50% of participants reported complete abstinence for at least 7 days and this remained stable at 3 months, dropping to approximately 40% at 6 months.
At all time points, urine screens were negative for approximately 40% of participants. In contrast, abstinence was reported by approximately 10% of the control group at the end of treatment.
Similarly, mean number of cannabis-use episodes per week was substantially decreased, according to the last-observation-carried-forward analysis. Mean use (past 7 days) at baseline was 27 for the active-treatment group and 21 for the delayed-treatment group.
After the intervention, this dropped to 7.4 per week with treatment but rose to 25 per week for the control group. At 6 months' follow-up, mean weekly use was 12 in the treatment group and 20 in the control group.