Predictors of favorable outcome following naltrexone treatment.

In order to determine the type of patient most likely to benefit from opiate antagonist therapy, a series of multivariate regression analyses were performed on a sample of male veterans who completed induction on naltrexone. Patient background characteristics, demographic factors and during-treatment variables were used to predict outcome measured at 1-month follow-up. Employment at the start of naltrexone and length of naltrexone therapy were significantly related to better outcome at 1-month follow-up. Treatment duration was clearly the best outcome predictor. The finding that at least 30 days of naltrexone therapy was necessary for significant improvement at 1-month follow-up but that longer periods of treatment were not necessarily associated with greater gains suggests that treatment can be limited and still be relatively successful. A second set of analyses attempted to discover patient characteristics predictive of longer treatment duration. Results showed that patients who were employed and/or married at the start of naltrexone therapy were more likely to stay in treatment longer. Similar results have been obtained by others suggesting that these patients have the best family and social supports to sustain a positive treatment outcome. In addition, they may also be more 'motivated' since they have the most to lose personally and financially by readdiction.