The Informant AD8 Can Discriminate Patients with Dementia From Healthy Control Participants in an Asian Older Cohort.

OBJECTIVES: The informant-AD8 (i-AD8) was found to be reliable in detecting cognitive impairment and dementia in tertiary and primary health care settings. We evaluated the discriminability of the i-AD8, as compared to other brief cognitive measures, and its combination with the 5-minute Montreal Cognitive Assessment (MoCA) and Mini-Cog in detecting very mild dementia in an Asian older cohort. DESIGN: The Epidemiology of Dementia in Singapore (EDIS) study recruited participants from a population-based eye disease study who were of Chinese, Malay, and Indian ethnicities. SETTING AND PARTICIPANTS: Participants aged ≥60 years were clinically assessed and diagnosed using the Clinical Dementia Rating (CDR) scale. Of the 761 participants recruited, 526 (69.1%) had no dementia (CDR = 0), 193 (25.4%) had very mild dementia (CDR = 0.5), and 42 (5.5%) had dementia (CDR ≥ 1). MEASURES: Participants were administered the Mini-Mental State Examination, MoCA, Mini-Cog, and a local neuropsychological battery. Their informants were interviewed using the i-AD8. Receiver operating characteristic analyses were conducted to establish the optimal cut-off points, and all discriminatory indices were calculated. RESULTS: The i-AD8 was good and equivalent to other cognitive tools in detecting dementia [area under the curve (AUC) = 0.89, sensitivity = 0.76, and specificity = 0.94] but only fair in detecting very mild dementia (AUC = 0.69, sensitivity = 0.62, and specificity = 0.73). Combination of the i-AD8 with 5-minute MoCA or Mini-Cog in compensatory or in conjunction showed minimal improvement to the clinical utility for dementia or very mild dementia. All scales yielded a high rate of false positives (positive predictive value < 0.70). CONCLUSIONS AND IMPLICATIONS: The i-AD8 has good discriminatory power in detecting dementia (CDR ≥ 1) and is brief enough to be applied as an effective screening tool in the community. However, the i-AD8 and other cognitive tools lacked classification accuracy in detecting very mild dementia (CDR = 0.5).

Duke Scholars

Author Tien Yin Wong Ophthalmology