The present study indicates that a manualized treatment focused specifically on changing the social environment can lead to lasting adaptive changes in the social network of alcohol dependent patients, and that these changes are predictive of lasting improvement in drinking outcome. No other study to date has been able to demonstrate lasting effects on drinkers' social environments. As in our earlier report (Litt et al., 2007), AA attendance and increasing the number of non-drinking friends in the social network were strong (direct and indirect) predictors of outcome, appearing to result in increased abstinence in part due to effects on self-efficacy. The program, however, did not work for everyone. Almost 30% of patients in the NS conditions had 2 or fewer abstinent friends throughout the 2 years of the study, and 33% attended no AA meetings during the entire study period. The reasons for this are not clear. Additional treatm development will be needed to maximize the effectiveness of this type of intervention.
