Association between living arrangements and time to drop out in patients between 18 and 29 years of age, under treatment for substance abuse disorders in Chile, 2010–2019

Abstract Substance use disorders (SUDs) are the leading cause of premature death and disability in the Americas, causing approximately 47% of deaths in the world’s adult population, posing an enormous public health challenge. One of these challenges is treatment dropout, which significantly compromises the efficacy of SUD interventions. Despite the implementation of advanced monitoring programs in Chile, evidence concerning the medium- and long-term effects of SUD treatment remains limited. This retrospective cohort study analyzed 23,979 emerging adults (18–29 years) receiving public SUD treatment in Chile between 2010 and 2019, examining the association between living arrangements at treatment entry (alone, with family of origin, or with partner/children) and time to treatment dropout, using IPTW (multinomial-logistic propensity scores) with weighted Kaplan–Meier estimation and restricted mean survival time (RMST), stratified by out-patient and in-patient treatment settings. Survival analyses showed that individuals living with family of origin or with partner/children had higher probabilities of remaining in treatment compared to those living alone, particularly in in-patient programs at 6 months (0.54 and 0.57 vs. 0.41) and 12 months (0.43 and 0.44 vs. 0.33). RMSTs confirmed longer retention among those living with family or a partner/children than among those living alone, especially in in-patient programs (one-year RMST: 0.60 and 0.62 vs. 0.49), where the two co-living groups did not differ; in out-patient programs, differences were modest, and the most consistent contrast was family of origin versus partner/children. The study emphasizes the crucial role of social bonds, particularly familial and relational ties, in influencing treatment outcomes. In conclusion, this study underscores the necessity to consider social support when formulating effective SUD treatment strategies and the potential positive impact of familial and relational bonds, especially during the critical phase of emerging adulthood.