Abstinence reinforcement maintenance contingency and one-year follow-up

Relapse to drug use is often seen when contingencies designed to reduce drug use are discontinued. This paper reports on a stepdown maintenance contingency and 1-year follow-up in 110 patients who were maintained on methadone (50 or 70 mg/day) and who had completed a contingency management trial targeted to decreasing their opiate use. In the prior study (induction phase, 8 weeks) participants received vouchers for each opiate-negative urine screen or noncontingently.

In this study (maintenance phase, 12 weeks), participants were rerandomized to receive vouchers and take-home methadone doses contingent on providing opiate-negative urine specimens (N=55) or noncontingently (N=55). Since participants had been rerandomized from induction-phase contingencies, most study data were analyzed as if from a 2 x 2 (inductionxmaintenance) design. Follow-up interviews were conducted at 3, 6, and 12 months after study participation.

Patients who received the maintenance contingency following an 8-week induction contingency had better outcomes than those who received noncontingent incentives in either the maintenance or induction phases of the trial. Good outcome at follow-up was predicted by enrollment in methadone maintenance after the study. Significantly more participants in the maintenance contingency group transferred directly to another methadone program.

These findings support the therapeutic value of extending the duration of contingency management and long-term methadone maintenance.