The Mini-Addenbrooke’s Cognitive Examination (M-ACE) as a brief cognitive screening instrument in Mild Cognitive Impairment and mild Alzheimer’s disease

ABSTRACT The Mini-Addenbrooke’s Cognitive Examination (M-ACE) is a brief cognitive screening test that evaluates four main cognitive domains (orientation, memory, language and visuospatial function) with a maximum score of 30 points and administration time of five minutes. Objective: To assess the performance of healthy elderly, MCI patients and mild AD patients using the Brazilian version of the M-ACE. Methods: The test was applied to a group of 36 Mild Cognitive Impairment (MCI), 23 mild Alzheimer’s Disease (AD) and 25 cognitive healthy elderly. All participants were aged ≥60 years. Results: The M-ACE displayed high internal consistency (Cronbach alpha >0.8; 95% CI 0.7-0.8) and proved effective for differentiating the AD group from MCI and control groups, providing superior accuracy than the MMSE (the cut-off point of 20 points had the highest sensitivity and specificity – 95.6% and 90.16% respectively, with a high area under the curve – AUC=0.8; 95% CI 0.7-0.9). Performance on the M-ACE was strongly correlated with that of the MMSE and Functional Activities Questionnaire (FAQ). The M-ACE was not accurate in discriminating MCI from control subjects. Conclusion: The M-ACE is a brief screening test which provided high accuracy for diagnosing AD in this sample. The suggested cut-off point in this study was 20 points for AD