Questionable utility of the Montreal Cognitive Assessment (MoCA) in detecting cognitive impairment in individuals with comorbid PTSD and SUD.

Posttraumatic stress disorder (PTSD) is frequently comorbid with substance use disorder (SUD) in individuals seeking treatment for substance use. Further, SUD and PTSD are individually associated with cognitive impairment (CI) and poor treatment outcomes. Despite the frequent use of the Montreal Cognitive Assessment (MoCA) as a screening tool for CI, the validity of the MoCA has not been established in individuals with comorbid SUD-PTSD. We assessed the criterion validity of the MoCA in 128 participants seeking inpatient medically-assisted detoxification using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) as a reference for CI. The correlation between the RBANS and MoCA was weaker in those with SUD-PTSD (r = .32) relative to SUD alone (r = .56). Receiver operating characteristic (ROC) curves demonstrated that the MoCA had moderate-to-high ability to discriminate CI in individuals with SUD alone, with an area under the ROC curve of .82 (95% CI .69-.92) and optimal cutoff score of ≤23. However, in individuals with comorbid SUD-PTSD, the ROC analysis was not significant. Results suggest that PTSD, when comorbid with SUD, reduces the criterion-related validity of the MoCA. We recommend exercising caution when classifying CI in individuals with SUD-PTSD using the MoCA and suggest reducing the cutoff score to ≤23 in order to limit the rate of false-positive CI diagnoses in SUD-PTSD populations.

Improving our understanding of the relationship between emotional abuse and substance use disorders: the mediating roles of negative urgency and posttraumatic stress disorder.

Background: Emotional abuse is associated with an increased risk for substance use disorders (SUDs) as well as with negative urgency and posttraumatic stress disorder (PTSD) following a subsequent trauma. Both negative urgency and PTSD are key contributors to the relationship between emotional abuse and SUDs when examined separately. A comprehensive model including both factors can inform models of PTSD-SUD comorbidity. Furthermore, the comparison of these mechanistic roles in emotional versus other types of abuse can shed light on the specificity of these effects. Objectives: The present study tested whether negative urgency and PTSD symptom severity serially mediated the relationship between emotional abuse and substance use across two separate samples. Method: Participants were recruited from a detoxification center and completed a battery of surveys examining abuse history, PTSD symptom severity, and impulsivity measures including negative urgency and substance use history during the last 3 months. The samples consisted of predominantly (59% and 62%) males with an average age of 35 (age range: 18-65). The majority of participants (90% and 93%) were Caucasian. Results: Study 1 (N = 368) and Study 2 (N = 274) both found that negative urgency and PTSD symptom severity serially mediated the relationship between emotional abuse and substance use. When comparing indirect effects, both contributed equally. Conclusion: These findings suggest that negative urgency and PTSD symptom severity together account more for the link between emotional abuse and SUDs than either alone and argue for the inclusion of negative urgency in models of PTSD-SUD comorbidity.