Endotoxin Exposure to Examine the Role of Inflammation in Alcohol Use

The study design consists of a randomized, double-blind, placebo-controlled study of low dose endotoxin. Individuals with current AUD (n=32) and matched controls without AUD (n=32) will be randomly assigned to receive a single intravenous (I.V.) infusion of either low dose endotoxin (0.8 ng/kg of body weight) or placebo (same volume of 0.9% saline solution) to determine the acute and protracted role of inflammation in alcohol use.

Participants will be recruited from the community through campaigns in radio, buses, social media, and print publications. After a telephone interview, eligible individuals will complete in-person screening to assess for presence of DSM-5 alcohol use disorder and additional inclusion/exclusion criteria. Eligible participants will complete a physical exam to assess medical safety, including EKG and laboratory tests. Participants who pass the physical exam will then be randomized to an experimental condition (i.e., endotoxin vs. placebo). Randomization will be stratified by sex (male versus female) and AUD (moderate versus severe). Participants will complete an alcohol cue-exposure paradigm in the lab 2 hours post infusion, the time of peak cytokine response. Plasma levels of inflammatory cytokines (i.e., interleukin-6 (IL-6) and tumor necrosis factor-α (TNF- α)), mood, and alcohol craving, will be assessed at baseline and then hourly for six hours post infusion. Following the infusion, all participants will complete a 7-day follow-up phase consisting of daily diary surveys of mood, alcohol craving, and alcohol consumption. The adverse events will be managed by study nurse practitioners during the endotoxin challenge.