The results of the present study raise questions regarding the specificity of existing criteria for the subtypes of MCI, with these results indicating a high degree of instability in classification over time. In addition, the results suggest that multidomain MCI is the most reliable precursor stage to the development of AD.

The results indicate that a-MCI and na-MCI display a stable pattern of deficits to attention, working memory, and executive function. The decline in simple sustained attention in a-MCI and n-MCI groups and to divided attention in a-MCI may be early indicators of possible transition to dementia from MCI. However, further research is required to determine this.

The association between level of educational attainment and cognitive performance is well studied. People with higher education perform better across a broad range of cognitive tasks. However, there is uncertainty as to whether education moderates the trajectory of age‐related cognitive decline. This review paper addresses the potential link between education and age‐related cognitive decline by evaluating relevant research published since 2000. Studies reporting data on education and its association with the rate of cognitive decline across various cognitive domains were reviewed. A total of 10 studies were identified with a mean follow‐up period of 7.6 years; each contained a population‐based, non‐demented sample. In the majority of studies, results showed that education did not moderate age‐associated cognitive decline. The few studies that did find an association between education and decline in specific cognitive functions should be interpreted with caution because of methodological issues. The literature reveals little consistent evidence that normal age‐related cognitive decline is moderated by education attainment. This supports a passive theory of cognitive reserve: people with a higher level of education will continue to perform at a higher level of cognitive functioning than their lower educated peers, which may delay the onset of impairment in the future.

Mild cognitive impairment (MCI) has emerged as a classification for a prodromal phase of cognitive decline preceding the emergence of Alzheimer's disease (AD). We examined neuropsychological functioning in a sample of 60 adults with amnestic-MCI (a-MCI), 32 with subjective complaints of memory impairment (subjective-MCI, s-MCI), 14 with mild AD, and 25 age-matched controls. Both the a-MCI and s-MCI groups displayed impaired attentional processing, working memory capacity, and semantic language, with a-MCI displaying additional impairments to verbal and/or visual memory. These results indicate that further research is needed to examine cognitive decline in nonamnestic variants of MCI.

The THBP commenced in 2011 and is expected to run for 10-20 years duration. To date, a total of 383 participants have been recruited into the THBP.