Using a randomized controlled trial to test whether modifications to contingency management improve outcomes for heavy drinkers with serious mental illness

Abstract

BackgroundIn contingency management (CM), individuals receive rewards for alcohol abstinence. CM is associated with reduced alcohol use in adults with co-occurring serious mental illnesses (SMI). Pre-treatment urine ethyl glucuronide (uEtG) levels equivalent to daily heavy drinking (uEtG >349ng/mL) are associated with poor response to CM. Modifications to CM are needed to improve outcomes for non-responders. AimsTo determine if pre-treatment heavy drinkers, defined by uEtG, with SMI achieve higher levels of alcohol abstinence when they receive an increased magnitude of reinforcement for abstinence (High-Magnitude CM) or reinforcers for reduced drinking, prior to receiving reinforcers for abstinence (Shaping CM), relative to those who receive typical low-magnitude abstinence based CM (Usual CM). Additionally, variables in the Addictions Neuroclinical Assessment model will be examined as treatment response moderators. MethodsParticipants (N=400) will be recruited from two urban mental health organizations and complete a 4-week induction period where they will be reinforced for submitting samples for uEtG testing. Participants who attain a mean uEtG >349mg/mL will be randomized to receive either Usual CM, High-Magnitude CM, or Shaping CM for 16weeks. Differences in abstinence, assessed by uEtG, will be examined during treatment and during a 12-month follow-up. Measures of negative emotionality, alcohol reinforcer salience, and executive functioning will be gathered at study intake and used to predict treatment outcomes. DiscussionThis novel approach to CM will use an alcohol biomarker to identify those at risk for treatment non-response and determine if adaptations to CM might improve outcomes for this group.