Impact of motivational changes on drinking outcomes in pharmacobehavioral treatment for alcohol dependence

Psychological factors such as motivation to change and self-efficacy influence drinking outcomes in alcohol-dependent individuals who are enrolled in pharmacobehavioral studies. Previous results from our research clinic indicated that initial stage of change of heavy drinkers enrolled in a pharmacobehavioral trial was significantly associated with alcohol consumption. However, overall empirical findings regarding the consistency and extent of the connection between motivational factors and behavior are mixed. This may be in part because of the impact of changes in motivation over the course of treatment and/or characteristics of the individuals receiving the intervention. Our goal in the present study was to examine the extent to which levels of motivation and self-efficacy changed during the treatment phase of a pharmacobehavioral treatment trial, and the extent to which these variables affected drinking behavior in subsets of alcohol-dependent individuals.

We conducted an exploratory evaluation of changes in motivation, temptation to drink, confidence to abstain, and drinking behavior over time during the treatment phase of a pharmacobehavioral study involving 321 alcohol-dependent individuals. We also examined the extent to which individual variables such as initial drinking severity, onset of alcohol dependence, and medication status influenced changes in motivation, self-efficacy, and drinking behavior.

Participants reported improvements in motivation to change, self-efficacy for change, and drinking behaviors over the course of treatment. As hypothesized, motivation to change and self-efficacy for change were related to specific dimensions of posttreatment drinking. Heavy drinkers reported more improvement in drinking behaviors than did nonheavy drinkers. Early-onset drinkers who were on medication reduced their drinking more than those on placebo, and these drinking changes appear to be partially mediated by reductions in temptation.

Reductions in drinking occur and are predicted by increased motivation to change, reduced temptation to drink, and increased confidence to abstain in this population of alcoholic-dependent individuals. Early and late onset and heavy drinkers and those taking medications displayed differential changes in drinking behavior, some of which were explained by the mediating effects of self-efficacy. This is a first step in understanding more about which alcoholic individuals respond best to treatment and what mechanisms may be involved in the changes in drinking and drinking-specific changes in frequency and intensity of drinking.