Identifying those with cognitive impairment

March, 2012

A brief questionnaire designed to identify those with Alzheimer’s has been found to be useful in also identifying those with MCI. A large study confirms the value of such tools but also points to their limitations

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.

Reference: 

Related News

Studies linking head trauma with increased risk and earlier age of onset for Alzheimer's disease have yielded contradictory results.

A survey of 7,072 older adults in six provinces across China, with one rural and one urban community in each province, has identified 359 older adults with dementia and 328 with depression.

A survey of 7796 older adults (65+) living in three geographic areas in England has allowed us to compare dementia rates over time, with an identical survey having been taken between 1989 and 1994. The overall prevalence of dementia fell significantly, from 8.3% to 6.5%.

A large Danish study comparing two groups of nonagenarians born 10 years apart has found that not only were people born in 1915 nearly a third (32%) more likely to reach the age of 95 than those in the 1905 cohort, but members of the group born in 1915 performed significantly better on tests of

A five-year study involving 525 older adults (70+) found 46 had Alzheimer’s or aMCI and a further 28 went on to develop the conditions.

A three-year study involving 152 adults aged 50 and older, of whom 52 had been recently diagnosed with mild cognitive impairment and 31 were diagnosed with Alzheimer's disease, has found that those with mild or no cognitive impairment who initially had amyloid-beta plaques showed greater cogniti

More evidence for early changes in the eye in Alzheimer’s disease comes from a study involving both rats and postmortem human retinas.

Blocking a receptor involved in inflammation in the brains of mice with severe Alzheimer’s produced marked recovery in blood flow and vascular reactivity, a dramatic reduction in toxic amyloid-beta, and significant improvements in learning and memory.

A multi-year study involving 207 healthy older adults, in which their spinal fluids were repeatedly sampled and their brains repeatedly scanned, has found that disruptions in the default mode network emerges about the same time as chemical markers of Alzheimer’s appear in the spinal fluid (decre

An analysis of the anatomical connectivity in the brains of 15 people with Alzheimer's disease, 68 with mild cognitive impairment and 28 healthy older individuals, has found several measures showed disease effects:

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news