Contingency Management Intervention Targeting Co-Addiction of Alcohol and Drugs Among American Indian Adults: Rationale, Design and Methodology

Background: American Indian (AI) adults have some of the highest alcohol abstinence rates compared to the overall U.S. population. Despite this, many AI communities are more likely to concurrently use alcohol and illicit drugs, and are less likely to participate and remain in typical outpatient treatment for alcohol and other drug use. Nevertheless, there is limited knowledge about effective interventions targeting alcohol and drug co-addiction among AI adults. Contingency management (CM) is a behavioral intervention designed to increase drug abstinence by offering monetary incentives in exchange for drug negative urine samples. CM has been underutilized in the treatment of co-addiction among AI communities.

Aims: To evaluate and describe a culturally-tailored CM intervention to increase alcohol and other drug abstinence among AI adults.

Methods: This 2x2 factorial, randomized controlled trial (RCT) currently includes 94 AI adults with alcohol and/or drug-dependence who are seeking treatment. Participants were randomized into 1 of 4 groups that received: 1) CM for alcohol, 2) CM for other drug, 3) CM for both substances, or 4) no CM for either substance. We present descriptive, baseline data to characterize the sample and describe the modified CM approach that is specific to the community wherein this trial is being conducted.

Results: 94 eligible participants were randomized to the 4 groups. The sample is 48.9% male, with an average age of 36.0 years (SD= 10.3 years). At baseline, 50.0% of participants self-reported methamphetamine as their most used drug, 37.2% self-reported cannabis and 12.8% self-reported prescription opiates as their most used drug. Among randomized participants, 47.9% tested positive for cannabis, 44.7% tested positive for alcohol, 25.5% tested positive for methamphetamine, 18.1% tested positive for amphetamines, and 2.1% tested positive for opiates. The randomized groups did not significantly differ across any of the baseline characteristics (p > 0.05).

Conclusions: This is the first study we are aware of to examine a culturally tailored CM intervention targeting co-addiction of two substances among AI adults. Through a tribal-university partnership to adapt, implement, and evaluate this trial, we will increase the literature on evidence-based addiction treatments and research, while improving trust for addiction interventions among AI communities through ongoing collaboration. Moreover, the scientific community will continue to learn about how best to adapt various interventions in hopes of optimizing treatment outcomes among diverse AI communities.