Screening for Cognitive Impairment in Asian Substance-Dependent Patients: MMSE versus MoCA

Background: Cognitive Impairment (CI) is common and associated with poor outcomes among substance-dependent patients. The Montreal Cognitive Assessment (MoCA), a screening tool for CI has demonstrated superiority over the routinely used Mini Mental State Exam (MMSE) in multiple clinical populations, yet is rarely used in addiction settings or studies. The current study describes the performance of the two instruments in a sample of Asian substance-dependent patients. Methods: The MMSE and MoCA were administered to 104 drug or alcohol-dependent inpatients 8 days after inpatient detoxification to identify those with CI. Total scores and task errors on common cognitive domains, and the level of agreement (Kappa coefficient) between the two screening tools in terms of identified cases of CI using MMSE (score < 24) and MOCA (score < 26) were examined along with the acceptability of the MoCA. Results: CI was identified in 76% of patients using the MoCA (M = 22.7) and only 5.8% using the MMSE (M = 27.0). Kappa agreement was exceptionally poor (κ = 0.05) and significantly more task errors were observed on the MoCA relative to MMSE domains. The acceptability of the MoCA was generally high, despite a majority (85%) finding it to be at least somewhat demanding. Conclusions: The MoCA detected far more cases of CI than the MMSE which may reflect its inclusion of items assessing executive functioning. Whilst validation studies are needed to determine its sensitivity and specificity with an Asian population, these initial findings provide further evidence of its promise as a more suitable screening tool for CI in substance-dependent patients.