Measuring cognitive impairment in young adults with polysubstance use disorder with MoCA or BRIEF-A - The significance of psychiatric symptoms.

INTRODUCTION

Chronic polysubstance use disorder (PSUD) is associated with cognitive impairments. These impairments affect the quality of life, occupational functioning, and the ability to benefit from therapy. Psychological distress also affects neurocognitive status, and impaired neurocognition characterizes several psychiatric conditions. Neurocognitive assessment is thus of importance but faces several interpretive challenges. One is disentangling the link between psychological distress and cognitive impairment. This paper investigates the associations between psychological distress and two cognitive screening tools, the Montreal Cognitive Assessment (MoCA) and the Behavior Rating Inventory of Executive Function - Adult Version (BRIEF-A) in young adults with PSUD.

MATERIAL AND METHODS

This study included 104 patients with PSUD recruited from the Norwegian Stayer study. Participants completed the MoCA, a self-report measure of executive functioning (EF), the BRIEF-A, and the Symptom Checklist 90 Revised, a measure of psychiatric symptoms (SCL-90-R). Cognitive impairment was diagnosed in accordance with previously published cutoff scores for the MoCA and BRIEF-A. Correlation analysis and multiple logistic regression were used to evaluate the association between cognitive impairment identified with the MoCA or BRIEF-A and psychological distress.

RESULTS

More than a third (34.6%) of patients scored below the threshold for cognitive impairment on the MoCA. On the BRIEF-A, 63.2% of participants reported executive problems that exceeded what was expected based on previously published norms. SCL-90-R scores were, as expected, elevated when compared with normative scores. Logistic regression analysis demonstrated a significant association between cognitive impairment identified by the BRIEF-A and scores on the SCL-90-R Global Severity Index (OR = 17.3, 95% CI: 4.4-68.8, p < 0.001) and age (OR = 0.7, 95% CI: 0.6-0.9, p = 0.003). Cognitive impairment identified by the MoCA was not significantly associated with demographic variables or SCL-90-R GSI score in multiple regression analysis.

CONCLUSIONS

Our study indicated that the MoCA is a measure of cognitive impairment that is independent of psychological distress, as measured with the SCL-90-R, whereas the BRIEF-A Global Executive Composite is strongly associated with distress. This suggests the need to interpret BRIEF-A results within a broad differential diagnostic context, where the assessment of psychological distress is included. The findings support that performance-based assessment such as the MoCA could reduce the impact of psychological distress in cognitive screening.