Background <p>Therapeutic Communities (TCs) are long-term residential treatment settings for individuals with substance use disorders, who often present with neuropsychological impairments. These impairments may influence treatment retention, yet little is known about their evolution in TCs or their association with dropout. This study aims to: (1) identify early risk factors for dropout; (2) investigate the potential recovery from the risk of neuropsychological impairment during an 8-mont stay in a TC; and 3) identify variables at TC entry that may predict the risk of neuropsychological impairment during follow-up.</p> Methods <p>Fifty-seven residents from 3 French TCs completed clinical, substance use, and medical assessments, along with a neuropsychological screening (BEARNI) at entry. Twenty-four completed the 8-month follow-up.</p> Results <p>The dropout rate was 47%. The only significant predictor of dropout was the BEARNI total score, with residents at lower risk of neuropsychological impairment more likely to leave the TC prematurely. Among completers, BEARNI total scores improved at follow-up, primarily explained by improvements in balance rather than in cognitive areas. Lower education, unemployment, recent alcohol use, depressive symptoms, and a history of hepatic disease were consistently associated with a higher risk of neuropsychological impairment at both time points.</p> Conclusions <p>Unlike other treatment settings, the TC care framework may be particularly appropriate and supportive for residents who are more cognitively vulnerable, as they may be better able to benefit from TCs. Motor recovery among those who remain in treatment is encouraging. However, demographic, addiction-related, and comorbidity factors are consistently associated with the risk of neuropsychological impairment, both at baseline and after 8 months, suggesting a stable and persistent influence over time.</p> Clinical trial number <p>Not applicable.</p>