The development of a dementia disorder (like Alzheimers disease or Vascular dementia) is a process that takes years of maybe even decades. The period when cognitive deficites may be detected, although the person does not fulfill the diagnostic criteria for dementia, is often called the preclinical phase. Since treatment is more effective the earlier it is started, early diagnosis is benificial.
The Kungsholmen Project was a longitudinal population-based study targeting parsons living in the Kungsholmen parish who were 75 year old or older on October 1, 1987. These persons were subjected to a number of tests approximately every 3 years until 2000, when most of them had passed away. The tests included a number of cognitive tests, testing global cognitive ability, primary memory, episodic memory, visuospatial ability and verbal ability. At each test occasion, each person is classified as either having a type of dementia or being healthy (controls). Between follow-ups some of the controls developed dementia and the test-results of the previous testing of these were compared to those who remained healthy. Substantial differences in performance of these two groups were found for many of the cognitive tests, but the overlap between the two groups is large. My contribution to the project will be to combine the results of different tests to develop av classifier that can predict who runs the risk of developing dementia within 3 years. Since treatment is different, it would also be desirable to distinguish between Alzheimers disease (AD) and Vascular dementia (VaD), although this may prove difficult. Making a differential diagnosis between VaD and AD is not always a straightforward task. Furthermore, the cause of the dementia is very often a mixture of the two, especially in the oldest age groups.
