Detecting Dementia Earlier

Overview

Aims 1. To determine whether the 4 Mountains test of allocentric (i.e. viewpoint-independent) spatial memory, and tests of memory for a recent experience (e.g. watching a brief video), to diagnose the early stages of Alzheimer's disease. 2. We operationalise this as the ability of these tests to predict whether or not an individual progresses from having some cognitive difficulties (diagnosed as 'mild cognitive impairment' MCI) to subsequently developing Alzheimer's disease up to two years later. 3. To assess whether the ability to diagnose early stages of Alzheimer's disease can be improved by combining the scores from different memory tests, from questionnaires assessing spatial and social aspects of everyday life. 4. To assess whether scores on the spatial memory test are correlated with patients' reports of their everyday spatial memory, using a newly-developed questionnaire. Outcome Measures Primary study objective: To determine the ability of allocentric spatial and episodic memory test performance to predict progression from mild cognitive impairment (MCI) to Alzheimer's disease. Secondary outcome measure 1. To assess to what extent social characteristics of everyday life may impact upon progression from mild cognitive impairment (MCI) to Alzheimer's disease. 2. To correlate allocentric spatial test performance with real-world spatial ability as assessed through a novel spatial questionnaire.

In recent years, the need for tests that reliably diagnose the early stages of Alzheimer's disease (AD) with high accuracy has been strongly emphasised. Detecting AD in its earliest stages increases the likelihood that therapeutic agents (e.g. newly-developed drugs) and interventions (e.g. changes in diet and exercise) can prolong the period of high-quality, independent living and reduce the impact on patients, families and care providers. An ideal test would have the sensitivity to detect everyone who has early-stage AD, while simultaneously not giving a 'false alarm' to anyone who shows some age-related impairments in cognition but who does not have early-stage AD. Secondly, an ideal test should be free and simple to administer on a national scale, without requiring extensive training on the part of the testers to set up, run, and interpret. Unfortunately, currently used tests do not come close to this ideal. There are some good biomarker-based tests for early stages of AD, but they are costly, highly invasive and in effect impossible to use for national screening purposes. MRI imaging of brain regions affected early in AD detects early AD no better than neuropsychological testing and whilst it is non-invasive, many patients find it aversive. Here, we propose to examine whether the use of spatial and episodic memory tests can get us nearer to this ideal, whether used singly, together, or in combination with other tests. The project has two stages. In stage 1, we will administer recently-developed spatial and episodic memory tests (along with more established neuropsychological tests) to patients who have recently been diagnosed with Mild Cognitive Impairment (MCI). At stage 2, clinical follow up (c.15-30 months after MCI diagnosis) we will establish those patients who have, and have not, progressed to AD. Analysis will then determine which tests at stage 1 best predicted progression-to-AD at stage 2.