LAUSR

INTRODUCTION Impulsivity has been consistently associated with poorer addiction treatment outcomes. However, impulsivity is a multifaceted construct and current evidence have failed to unravel which specific aspects explain this relationship. There is also limited research examining long-term outcomes. We aimed to examine the longitudinal association between baseline performance on a comprehensive battery of impulsivity measures and retention and relapse at the end of treatment. METHODS The sample comprised 68 participants with miscellaneous diagnoses of substance use disorders and polysubstance use patterns, enrolled in public residential therapeutic communities in Andalusia (Spain). At baseline, we applied measures of selective attention (Stroop), response inhibition (Affective Go/No Go), delay discounting (Monetary Choice Questionnaire; MCQ), and decision-making (Iowa Gambling Task; IGT). At the end of treatment (mean = 148.36 days, range = 22-289 days), we collected outcome measures of retention (coded by the clinical team as completion or dropout based on statewide practice guidelines) and relapse (defined as at least two separate alcohol/drug use episodes based on urine analyses). RESULTS Cox regression models showed that poorer decision-making in the IGT was associated with premature treatment dropout, whereas elevated commission errors in the Affective Go/No Go were associated with higher relapse rates. Selective attention and delay discounting were unrelated to outcomes. CONCLUSION Long-term based decision-making skills are important to commit to the complex and intensive treatment programs of therapeutic communities. The ability to withhold behavioural responses under positive affect is relevant to prevent relapse. Both skills should be assessed and potentially trained during therapeutic community treatment.