Abstinence-orientated residential rehabilitation of opioid users in Denmark: Do changes in national treatment policies affect treatment outcome?

Abstract

Aims: Significant changes in the Danish drug-abuse treatment system occurred from 1998 to 2008, allowing the opportunity to study their impact on outcomes for opiate dependent patients. This paper examines whether such changes are related to possible changes in abstinence rates of two cohorts of drug users. Methods: We compared survival curves and the month-by-month probability of abstinence between cohorts of drug abusers who were followed for one year after treatment for opioid dependence in 1998 (n = 305) and in 2008 (n = 204). Of the 1998 cohort, 192 were interviewed face-to-face and 61 were found through national drug-abuse treatment registers. Of the 2008 cohort 112 were interviewed face-to-face and 42 were found through national drug-abuse treatment registers. Results: Survival curves did not differ between the two cohorts. After controlling for age and gender, people from the 2008 cohort had a higher frequency of month-to-month rates of abstinence. A higher proportion of clients received new treatment after their index treatment in 2008. Clients from the 1998 cohort who did not receive new treatment used drugs more often than clients who did not receive treatment in 2008. At the same time, the proportion of clients who received residential rehabilitation treatment for opiate dependence increased substantially by 2008. Conclusions: Total abstinence rates are highly consistent over time and seem to change little with changes in systems of care. However, changes in care that improve access to treatment may reduce the overall burden of opioid addiction to both individuals and society.