THE MINI-MENTAL-STATE-EXAMINATION SCORE AND THE CLINICAL-DIAGNOSIS OF DEMENTIA

To set a working cutoff score for the referral to diagnostic examination, we evaluated 150 consecutive patients with complaints potentially related to dementia, using the Mini-Mental State Examination (MMSE). All patients were later given a complete, standardized work-up and diagnosis as part of our Alzheimer's Disease Patient Registry protocol. Dementia diagnosis was made, consistent with accepted criteria, by consensus of the physicians and psychologist. Diagnosis was reaffirmed after 1-year follow-up exam; 133 of the 150 original patients completed follow-up (80 dementia, 53 no dementia). We evaluated the initial MMSE score compared with the follow-up diagnosis. Sensitivity, specificity, and predictive values were calculated for MMSE scores ranging from 22 through 29. The conventional cutoff score of < 24 shows a sensitivity of 0.63 and a specificity of 0.96; sensitivity increased at higher cutoff scores. Multivariate analysis showed that educational level added significant prediction only at scores of greater than or equal to 27. We conclude that an MMSE score of 26 or 27 should be used as a cutoff score in symptomatic populations with similar educational and socioeconomic backgrounds when the goal is to miss few true cases. Population surveys where the expected prevalence is low may require a different cutoff score to indicate the need for further diagnostic evaluation.