Individualized Assessment and Treatment for Marijuana Dependence: Treatment Mechanisms

Marijuana is the most commonly used illicit drug in the US, but treatment for marijuana dependence is not fully effective. The most effective treatments to date have employed motivational enhancement (MET) plus cognitive-behavioral coping skills treatment (CB) and contingency management (CM) for abstinence. This proposal is a competitive renewal of our recently completed study to enhance coping and self-efficacy to improve marijuana outcomes in the long term. In the current proposal we are exploring the idea that more tailored teaching of coping skills may result in improved outcomes for marijuana-dependence than those seen thus far. The Individualized Assessment and Treatment Program (IATP) for marijuana dependent patients will employ experience sampling (ES) to determine the strengths and weaknesses of each patient in drug-use situations so that treatment can be tailored accordingly. Results from a pilot study indicated that IATP for alcohol dependent patients yielded better drinking outcomes at posttreatment than a packaged CB program (PCBT), that IATP patients reported greater use of coping skills than PCBT participants, and that posttreatment reports of coping skills were related to posttreatment drinking. Participants will be 275 men and women meeting criteria for marijuana dependence and randomly assigned to 9 sessions of treatment in one of 4 treatment conditions: Standardized MET plus CB (SMET-CB); SMET+ CM (SMET-CB-CM); IATP; or IATP + CM (IATP-CM). Patients in all treatments will engage in ES via cell-phone for two weeks prior to treatment, for a weekly period during treatment, for another week after treatment has ended, and for two weekly periods at months 8 and 14. In the IATP conditions, the information gathered from the pretreatment and during-treatment ES periods will provide data for a functional analysis of patients' drug use and urges to use. Therapists will use the information to address specific cognitions, affects, and behaviors that are adaptive and maladaptive, and will tailor a specific coping skills program with the patient. During-treatment experience sampling will allow adjustment of the treatment goals and procedures, making the treatment adaptive. In the SMET-CB conditions the experience sampling data will not be used in therapy, but will still provide in-vivo measures of drinking and coping skills. It is hypothesized that IATP conditions will yield significantly better coping skills acquisition than SMET-CB conditions, both at posttreatment and at extended follow-ups, and that change in coping skills will predict better outcomes for the IATP conditions. It is further predicted that the addition of CM to both IATP and SMET-CB will enhance short-term and long-term outcomes. The results will have implications for improved tailoring of treatment to patients' strength and deficits, and for the validity of the training of coping skills for relapse prevention. The data collected will shed light on the ways in which patients in treatment use coping skills in real-time contexts. Finally, the use of repeated ES periods will allow us to determine how treatment impacts thoughts, feelings and behaviors, and how these in turn affect outcome in the long and short term.