The MMSE and MoCA for Screening Cognitive Impairment in Less Educated Patients with Parkinson's Disease

Objective To explore whether the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) can be used to screen for dementia or mild cognitive impairment (MCI) in less educated patients with Parkinson's disease (PD). Methods We reviewed the medical records of PD patients who had taken the Korean MMSE (K-MMSE), Korean MoCA (K-MoCA), and comprehensive neuropsychological tests. Predictive values of the K-MMSE and K-MoCA for dementia or MCI were analyzed in groups divided by educational level. Results The discriminative powers of the K-MMSE and K-MoCA were excellent [area under the curve (AUC) 0.86-0.97] for detecting dementia but not for detecting MCI (AUC 0.64-0.85). The optimal screening cutoff values of both tests increased with educational level for dementia (K-MMSE < 15 for illiterate, < 20 for 0.5-3 years of education, < 23 for 4-6 years, < 25 for 7-9 years, and < 26 for 10 years or more; K-MoCA < 7 for illiterate, < 13 for 0.5-3 years, < 16 for 4-6 years, < 19 for 7-9 years, < 20 for 10 years or more) and MCI (K-MMSE < 19 for illiterate, < 26 for 0.5-3 years, < 27 for 4-6 years, < 28 for 7-9 years, and < 29 for 10 years or more; K-MoCA < 13 for illiterate, < 21 for 0.5-3 years, < 23 for 4-6 years, < 25 for 7-9 years, < 26 for 10 years or more). Conclusion Both MMSE and MoCA can be used to screen for dementia in patients with PD, regardless of educational level; however, neither test is sufficient to discriminate MCI from normal cognition without additional information.