Introduction
This study aims to clarify differences in mood, craving, and treatment response between reward and relief/habit individuals in a study of naltrexone, varenicline, and placebo. We hypothesized that relief/habit individuals would have a poorer mood during early abstinence and higher levels of alcohol craving than reward individuals. We hypothesized that reward individuals would demonstrate better drinking outcomes on naltrexone versus placebo.
Methods
Data were culled from a randomized, double-blind, placebo-controlled human trial of 53 individuals (18F/16M) with alcohol use disorder randomized to varenicline (n = 19), naltrexone (n = 15), or matched placebo (n = 19). In this 6-day practice quit trial, participants attempted to abstain from drinking and completed daily diaries. Participants were classified into reward or relief/habit subgroups based on self-reported motivation for drinking. Multilinear models tested differences in mood and alcohol craving between reward and relief/habit individuals. General linear models tested differences between reward and relief/habit individuals’ drinking outcomes on each medication versus placebo.
Results
Relief/habit individuals showed decreases in positive mood and increases in negative mood over the quit attempt across medications, compared to reward individuals (P’s < .05). Reward individuals’ tension decreased on naltrexone, while relief/habit individuals’ tension remained stable (F = 3.64, P = .03). Reward individuals in the placebo group had higher percent days abstinent than relief individuals in the placebo group (P < .001).
Discussion
This study suggests relief/habit individuals’ mood worsens during early abstinence. Our finding that reward individuals’ tension decreased on naltrexone and increased on placebo may suggest a clinical response to the medication.
