Indirect effect of social support for drinking on drinking outcomes: The role of motivation*

Objective: This study tested an integrated relapse model drawing hypotheses from both interpersonal and intra-individual relapse models. It was hypothesized that the relationships between alcoholspecific social support (support for drinking and support for not drinking) and drinking outcomes would be partially mediated by motivation. Method: Participants were 158 women with alcohol use disorders participating in two linked randomized controlled trials. One trial compared standard individual cognitive behavioral therapy (CBT) for alcohol use disorders with female-specific CBT for alcohol use disorders; the other compared alcohol behavioral couple therapy with blended individual CBT and alcohol behavioral couple therapy. Measures included the Important People Interview to measure social-support variables, the Timeline Followback to measure drinking variables, and the Stages of Change Readiness and Treatment Eagerness Scale to measure motivation. Results: Results of structural equation modeling suggested a mediational role of motivation in the relationship between support for drinking and drinking frequency. Individuals with more network support for drinking at baseline had less motivation for abstinence at the end of treatment, which predicted drinking frequency over the 6 months after treatment. The indirect effect of baseline support for drinking on 6-month follow-up drinking frequency was statistically significant. A similar, although only marginally significant, pattern was found for the relationship between support for not drinking and drinking frequency. Individuals with more social network for not drinking at baseline had more motivation at the end of treatment at the trend level, which in turn predicted 6-month follow-up drinking frequency. The indirect effect of baseline support for not drinking on 6-month follow-up drinking frequency trended toward signifi cance. Conclusions: This study offers preliminary evidence that motivation is one mechanism by which abstinence-specifi c social support affects treatment outcome. (J. Stud. Alcohol Drugs, 71, 930-937, 2010).