Long-Term Outcomes of Substance Use Treatment: A 20-Year Follow-Up Study in the Swedish Addiction Treatment System

Background: Research on the effectiveness of substance use treatment (SUT) has suggested varying degrees of success in improving long-term outcomes for individuals struggling with alcohol and drug dependency. While some studies have demonstrated favorable effects of SUT, particularly in the short term, evidence regarding its impact on long-term outcomes remains limited. This study aims to address this gap by conducting a 20-year follow-up of individuals enrolled in the Swedish addiction treatment system, providing insights into the trajectory of their substance use and associated outcomes over time.
Methods: The baseline study, conducted in Stockholm County between 2000-2002, involved interviews with 1865 adults who initiated SUT for substance use disorders. A subset of individuals (n=583) identified as being most severely affected, based on their Addiction Severity Index (ASI) scores, were selected. Utilizing both baseline interview data and data from national registers, the study examined long-term outcomes across various indicators from 2000 to 2020.
Results: Individuals identified as the most severely affected exhibited higher levels of alcohol and/or drug use at baseline, along with greater prior treatment experiences. Over the 20-year study period, a majority continued to engage in SUT and other medical interventions. Furthermore, indicators of social stability, such as employment status and reliance on social assistance, worsened over time. Notably, this group experienced higher rates of mortality, and they had more often mentions of alcohol or drugs on their death certificates.
Conclusion: These results emphasize the need for ongoing support and interventions tailored to address the complex needs of this population, with a focus on enhancing treatment effectiveness and promoting sustainable recovery pathways.