Current Research

An insight to the current research taking place at the Alzheimer Scotland Dementia Research Centre.

Summary: Patients who are diagnosed with probable Alzheimer's Disease (AD) are usually prescribed acetylcholinesterase inhibitors (AChE-I), which manage the symptoms of AD.

However, these drugs are not a cure, and they may not work for some patients. In this last case, patients will be delayed in reaching the most effective treatment. As such, it would be useful to be able to predict whether a patient will respond positively to treatment.

Recent research has shown that patients with AD have a distinct inability to remember bound visual information together. For instance, they have difficulty remembering an object that is composed of a shape and a colour.

This is a recurring impairment found specifically in AD, and is not seen in healthy ageing or depression. Furthermore, it can be seen in cases of genetic AD before the usual clinical markers (like a memory impairment) arise. This visual binding deficit is therefore a very sensitive indicator of AD.

My current research is an attempt to use visual binding as a tool to predict whether a patient taking AChE-Is will benefit from the treatment.

The goal of this research is to provide clinicians with a sensitive and early indicator of a patient's response to treatment, which would then be used to give the most suitable treatment to a patients as soon as possible.

Summary:  My research involves using item response theory (IRT) to examine the psychometric properties of the Addenbrookes Cognitive Examination-Revised (ACE-R). This assessment covers five domains, attention/orientation, verbal fluency, memory, language and visuo-spatial. Although the ACE-R has become a standard memory test for UK based memory clinics no one has yet applied IRT to any of its scales.

Using data collected from approximately 700 patients from the Scottish Dementia Research Interest Register who have all been tested on ACE-R IRT properties of the ACE-R will be examined. Using IRT we can establish a formal hierarchy of cognitive decline which also serves to examine internal validity, to improve construct validity by assessing any gaps in measurement and to also increase content validity. All of which enhance the interpretive power of this memory test.

With these novel contributions IRT provides a more in depth view of each patient's cognitive function, showing a pattern of cognitive decline. This research also allows further investigation of the relationship of scores on the ACE-R and correlates, for example educational background and level of support required.

Doing a later follow up of these patients will allow us to gain insights into progression and look to make predictions of cognitive change and adverse health events.

IRT methods can show how ACE-R items differ in their usefulness in assessing the total severity of symptoms and as such IRT can be used to select the most useful items to develop a briefer scale. Therefore another aim of this research is to look to the possibility of developing a shorter scale to assess cognitive decline without loss of measurement efficiency. The development of a brief powerful test would benefit both patients and clinicians.

Summary: Health service planning assumes a uniform spread of dementia across the country. However there is evidence that young-onset dementia, at least, is not randomly distributed geographical clusters have been developed. This has not been investigated for the much more common late-onset dementia.

Evidence of clustering of dementia would allow more efficient use of scarce health service resources but also, potentially more importantly, could help identify socio-enviromental factors that increase or decrease the risk of developing dementia. This opens the possibility of altering that risk and potentially protecting someone, at least partially, from developing dementia.

I am attempting to identify which of the participants in the 1932 Scottish Mental Survey have developed dementia using record linkage to hospital discharge and death certificate data, in addition to accessing a sample of primary care records. Mapping the location of these individuals at birth, age 11 (when they took part in the Survey) and at diagnosis will allow the geographical spread of dementia cases in a narrow age cohort in Scotland to be investigated.

Summary:  Apathy is a debilitating symptom of neurodegenerative disease and is characterised by reduced motivation relating to goal direct behaviour. It is a prevalent symptom associated with Alzheimer’s Disease (AD) that can often be difficult to detect while having a marked negative effect on disease progression.

Apathy is often regarded and assessed as a singular concept despite research showing it to have a multidimensional substructure related to motivational deficits of emotion, organizing and initiating behaviour. These different types of apathy effect functioning in different ways and have implications for adherence to treatment, both pharmacological and non- pharmacological. Currently, there is no direct or well- established method that assesses apathy in this particular, substructural form.

My research looks to develop and implement a new, more comprehensive apathy scale, which quantifies different apathetic subtype impairments through subscales. This new scale will assess patients with all severities of AD.

Following the validation of this new scale, research in to the relationship between apathy subtypes and neuropsychological impairment will be conducted as to attempt to build apathy profiles associated with different severities of AD and other neurodegenerative diseases.

The main aim of this research would be to establish this new apathy scale in a clinical setting, encouraging its use due the negative implications of apathy as a symptom, and its associated neuropsychological impairments, of neurodegenerative diseases.