Phosphatidylethanol-Based Contingency Management for Housing

The investigators will evaluate the efficacy of contingency management (CM) in reducing alcohol use in individuals experiencing unstable housing but who are currently housed in shelters. Participants will be 20-30 adults diagnosed with alcohol use disorder (AUD) and has a history or unstable housing or literal homelessness in the last year but is currently receiving housing through Catholic Charities Spokane or other locations. Individuals who demonstrate AUD and have measurable PEth \>ng/mL at the baseline visit will be randomized to receive Phosphatidylethanol-based CM treatment or non-contigent treatment.

The objective of this study is to determine whether CM intervention improves outcomes in the unstably housed population using alcohol biomarker phosphatidylethanol (PEth) and ethyl glucuronide (EtG) to test alcohol abstinence. In CM, participants receive tangible rewards for demonstrating drug abstinence while non-contingent intervention receive the rewards regardless of PEth and EtG results for alcohol.

The investigators propose to examine whether CM intervention, to reduce alcohol use to abstinence, is a feasible and acceptable treatment in supported housing. Additionally, this study will assess group differences (between PEth-based CM and non-contingent control) in alcohol abstinence, as assessed by PEth, EtG, and self-report. Characterization of group differences in housing status and other alcohol associated harms (e.g., physical and mental health, medical care, and incarceration) will also be analyzed.

A total of 20-30 participants receiving treatment as usual through Catholic Charities Spokane or other locations in the Pacific and Mountain Time Zones will take part. Participants with AUD and have PEth biomarker results above \>20 ng/mL, which indicates regular alcohol usage will be randomized to

1. 6 months of PEth-based CM for submitting alcohol-abstinent PEth results of 16:0/18:1 which is associated with abstinence in the past week, which is \<20 ng/ml PEth biomarker in the blood when abstinent for 14-28 days. Urine EtG results will be analyzed to verify PEth result findings,
2. 6 months of non-contingent control for submitting samples each week for the first 4 weeks then every 2 weeks for 4 weeks and then every 4 weeks until week 26. Control participants receive reinforcers regardless of the results of their PEth results. The primary outcomes will assess acceptability measured by attrition, Client Satisfaction Questionnaire-8 and qualitative interviews at weeks 4, 12, and 26. Other primary outcomes include assessment of the effectiveness of PEth-based CM on reducing alcohol use to abstinence and housing status.

The investigators will also be examining group differences in secondary outcomes including self-reported abstinence and heavy drinking assessed by the alcohol timeline follow back and urine EtG analyses. Other secondary outcomes include a) Addiction Severity Index Lite which assesses impact of alcohol us on psychiatric, legal, medical and family functioning, b) self-reported drug use and its severity.

Eligibility Criteria:
Inclusion Criteria:

1. Two heavy drinking episodes (Assigned Male at Birth \> 4 standard drinks (SDs), Assigned Female at Birth \> 3 SDs) in the prior 14 days OR \>14 drinks in the past 2 weeks, confirmed by a PEth level \>=20 ng/ml
2. DSM-5 diagnosis of a current Alcohol Use Disorder (AUD) as assessed by the Structured Clinical Interview for Diagnostic and Statistical Manual 5 (DSM-5);
3. Age \>=18 years;
4. Currently housed at Catholic Charities Spokane or other locations in the Pacific and Mountain time zones; and
5. Previously, literally homeless or unstably housed (e.g., couch surfing) for \> 1 month

Exclusion Criteria:

1. Current diagnosis of substance use disorder (other than AUD and tobacco), severe;
2. Inability to provide informed consent based on the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and/or age over 65 and Inability to provide informed consent based on the mini-Montreal Cognitive Assessment (mini-MoCA);
3. Alcohol withdrawal-related seizure or hospitalization in prior 12 months; and
4. Psychiatrically or medically unsafe to participate, as assessed by the PI.