New data from the ongoing validation study of the Alzheimer's Questionnaire (AQ), from 51 cognitively normal individuals (average age 78) and 47 aMCI individuals (average age 74), has found that the AQ is effective in identifying not only those with Alzheimer’s but also those older adults with mild cognitive impairment.
Of particular interest is that four questions were strong indicators of aMCI. These related to:
- repeating questions and statements,
- trouble knowing the date or time,
- difficulties managing finances, and
- decreased sense of direction.
The AQ consists of 21 yes/no questions designed to be answered by a relative or carer. The questions fall into five categories: memory, orientation, functional ability, visuospatial ability, and language. Six of these questions are known to be predictive of AD and are given extra weighting, resulting in a score out of 27. A score above 15 was indicative of AD, and between 5 and 14 of aMCI. Scores of 4 or lower indicate that the person does not have significant memory problems.
The questionnaire is not of course definitive, but is intended as an indicator for further testing. Note, too, that all participants in this study were Caucasian.
The value and limitations of brief cognitive screenings
The value of brief cognitive screenings combined with offering further evaluation is demonstrated in a recent large VA study, which found that, of 8,342 Veterans aged 70+ who were offered screening (the three-minute Mini-Cog), 8,063 (97%) accepted, 2,081 (26%) failed the screen, and 580 (28%) agreed to further evaluation. Among those accepting further evaluation, 93% were found to have cognitive impairment, including 75% with dementia.
Among those who declined further evaluation, 17% (259/1,501) were diagnosed with incident cognitive impairment through standard clinical care. In total, the use of brief cognitive screenings increased the numbers with cognitive impairment to 11% (902/8,063) versus 4% (1,242/28,349) in similar clinics without this program.
Importantly, the limits of such questionnaires were also demonstrated: 118 patients who passed the initial screen nevertheless requested further evaluation, and 87% were found to have cognitive impairment, including 70% with dementia.
This should not be taken as a reason not to employ such cognitive tests! There are two points that should, I think, be taken from this:
- Routine screening of older adults is undoubtedly an effective strategy for identifying those with cognitive impairment.
- Individuals who pass such tests but nevertheless believe they have cognitive problems should be taken seriously.
(2012). Informant-reported cognitive symptoms that predict amnestic mild cognitive impairment.
BMC Geriatrics. 12(1), 3 - 3.
Full text available at http://www.biomedcentral.com/1471-2318/12/3
(2012). Finding Dementia in Primary Care: The Results of a Clinical Demonstration Project.
Journal of the American Geriatrics Society. 60(2), 210 - 217.