Monitoring alcohol use in heavy drinking soup kitchen attendees

Rates of heavy alcohol use in soup kitchen attendees range from 30% to 38%, but these data are based entirely on self-reported drinking. Little is known about the intensity or frequency of drinking in this population. We assessed alcohol use transdermally every 30 min over a 3-week period among heavy drinkers who attended local soup kitchens. In addition to transdermal alcohol monitoring, participants were randomly assigned to daily breath alcohol monitoring with or without reinforcement for alcohol-negative breath samples (BrAC). Analyses assessed feasibility of transdermal monitoring and examined alcohol use based on BrAC, transdermal, and self-report data, as well as effect sizes for these metrics based on group assignment. Nineteen participants completed the 21-day monitoring period in full; three persons removed the anklet 3-16 days early due to hospitalization, impending hospitalization, or incarceration. Participants reported minimal impacts of the monitors, and severity ratings of side effects were mild. When using BrAC, transdermal, and self-report data, the percentage of non-drinking days was 93%, 58%, and 57%, and the longest duration of consecutive non-drinking days averaged 10.3, 7.2, and 5.7 days, respectively. About half of drinking days involved heavy drinking (5 + drinks). Self-report and transdermal drinking days correlated significantly, p < .001, but neither index was associated with BrAC. Group comparisons indicate small-to-moderate sized effects of reinforcement compared to no reinforcement for increasing the proportion of alcohol-negative breath samples and durations of consecutive non-drinking samples during the study when BrAC was the metric. Transdermal data and self-report data indicated a more complex pattern. Reinforcement participants drank more often but at lower quantities than monitoring (control) participants per both transdermal and self-report data. These data suggest that transdermal monitors are well tolerated and document substantial heavy drinking in this population. Soup kitchens users are in need of alcohol interventions, and soup kitchens may represent a novel opportunistic setting for intervention delivery for an important and growing health disparities population.