Investigating the Critical Period for Alcohol or Other Drug-Related Presentations Following Access to Residential Substance Use Treatment: a Data Linkage Study

Individuals who access residential treatment for substance use disorders are at a greater risk of negative health and substance-use outcomes upon exiting treatment. Using linked data, we aimed to identify predictive factors and the critical period for alcohol or other drug (AOD)-related events following discharge. Participants include 1056 individuals admitted to three residential treatment centres in Queensland, Australia from January 1 2014 to December 31 2016. We linked participants’ treatment data with administrative data from hospitals, emergency departments, AOD services, mental health services and the death registry up to December 31 2018. We used survival analysis to examine presentations for AOD-related events within two-years of index discharge. A high proportion of individuals (57%) presented to healthcare services for AOD-related events within 2 year of discharge from residential treatment, with the first 30 days representing a critical period of increased risk. Completing residential treatment (aHR = 0.49 [0.37–0.66], p < .001) and high drug-abstaining self-efficacy (aHR = 0.60 [0.44–0.82], p = .001) were associated with a reduced likelihood of AOD-related events. Individuals with over two previous residential treatment admissions (aHR = 1.31 [1.04–1.64], p = .029), identifying as Indigenous Australian (aHR = 1.34 [1.10–1.63], p < .001), alcohol as a primary substance (aHR = 1.58 [1.30–1.92], p < .001), and receiving a Disability Support Pension (aHR = 1.48 [1.06–2.06], p = 0.022) were at a greater likelihood. The high proportion of individuals that present to health and drug services for AOD-related events, especially in the first 30 days post-discharge, highlights the need for continued support following discharge from substance use treatment.