Background and objectives: This study examined the predictive value of cognitive functioning and PTSD symptoms for treatment dropout in individuals with Alcohol Use Disorder (AUD). Cognitive functioning is essential for successful treatment engagement and outcomes, yet cognitive impairment is common among individuals with AUD. Previous research suggests that both cognitive impairment and psychological distress may negatively affect treatment completion in Substance Use Disorders (SUDs). However, evidence within AUD populations remains limited, particularly regarding PTSD symptoms, which affect 30–70% of individuals with AUD. Identifying predictors of treatment dropout is important, as premature treatment termination is associated with relapse and poorer recovery outcomes, and may help facilitate targeted support for individuals at risk.

Methods: Ninety-one participants diagnosed with AUD and enrolled in inpatient addiction treatment at Jellinek clinics in Amsterdam and Utrecht were included in the study. Cognitive functioning was measured using the Montreal Cognitive Assessment (MoCA), while PTSD symptoms were assessed with the Jellinek PTSD Screening Questionnaire (JPSQ). Logistic regression analyses were conducted to investigate the predictive effects of cognitive functioning and PTSD symptoms on dropout, including their interaction effect. Additionally, a linear regression analysis examined differences in cognitive functioning between participants with and without PTSD symptoms.

Results: PTSD symptoms significantly predicted treatment dropout, with participants reporting PTSD symptoms showing a substantially higher probability of discontinuing treatment prematurely. Cognitive functioning, measured by the MoCA, did not independently predict dropout. Furthermore, no significant interaction effect between PTSD symptoms and cognitive functioning was found, although the study had limited statistical power to reliably detect small to moderate interaction effects. Participants with PTSD symptoms scored significantly lower on cognitive functioning compared to participants without PTSD symptoms.

Discussion/conclusion: The findings suggest that PTSD symptoms play an important role in treatment dropout among individuals with AUD, whereas cognitive functioning alone was not associated with dropout. The absence of an interaction effect should be interpreted cautiously due to limited statistical power. This study highlights the importance of considering trauma-related symptoms in AUD treatment and emphasizes the need for future research with larger samples and clinically diagnosed PTSD populations.

Keywords: Alcohol Use Disorder, PTSD symptoms, cognitive functioning, treatment dropout, MoCA, addiction treatment.