New Test for Early Detection of Alzheimer’s Disease developed by TCD Researchers

Posted on: 16 January 2008

A new test for the early detection of Alzheimer’s disease has been developed by the TCD Chair of Psychiatry, Professor Harald Hampel based at the Adelaide & Meath Hospital , Incorporating the National Children’s Hospital at Tallaght. The findings of a study led by Professor Hampel were recently published in the world leading peer-reviewed clinical journal, Neurology¹.

The study shows that the biological marker in the brain called p-tau 231 is a significant predictor of cognitive decline and conversion in the transition from the clinically at risk syndrome Mild Cognitive Impairment (MCI) to Alzheimer’s disease.

For the purpose of the international multi-centre study, 145 subjects were followed for 1.5 years. The results show that the biological marker of highly increased hyperphosphorylated tau-protein within the cerebrospinal fluid called p-tau 231 predicts the conversion from preclinical MCI to Alzheimer’s disease with about 80% accuracy.

The incidence of Alzheimer’s disease is projected to dramatically increase worldwide during the next decade. For Ireland , the projected increase will be approximately 43% within the next 20 years, entailing a large increase in cost for patient care treatment as well as their caregivers. An estimated 30,000 patients with dementia are living in Ireland , with the annual costs of treatment of these patients accruing to about €474 million (National Council on Aging and Older People, 2000, NUI).

Commenting on the significance of the new test and the general need for earlier detection of Alzheimer’s disease, Professor Hampel stated: “This is one of the first multi-centre controlled validation studies on early detection and prediction of Alzheimer’s disease and the first one using p-tau 231. It is important to note that we utilised an assessment period of 1-2 years, which is both relatively short and a clinically relevant time frame for the prediction of disease progression to Alzheimer’s disease”.

“With novel therapeutic compounds for the treatment and prevention of Alzheimer’s disease currently being developed by pharmaceutical companies, the early detection of the disease is pivotal to assess increased risk to develop Alzheimer’s disease at early stages. Our newly established interdisciplinary Alzheimer’s disease research team based both at Tallaght Hospital and at the Trinity College Institute of Neuroscience has gained an internationally leading position in the development of early neurochemical and neuroimaging diagnostics to bring effective therapy as early as possible to the affected patient, hopefully at a stage when destruction in the brain is still minimal or even reversible, a stage when patients will benefit most from novel
therapies”.

“To date the challenge for GPs and consultants in Ireland to accurately diagnose Alzheimer’s disease in earlier predementia stages is still enormous. Alzheimer’s disease in Ireland is still generally detected at a very late clinical endstage, most likely after decades of presymptomatic disease progression in the patient’s brain and after the development of severe behavioural
and psychological symptoms and loss of functional independence and quality of life as a reflection of severe widespread cell death in the brain”.

Notes to the editor
1. Neurology, is the official journal of the American Academy of Neurology. The peer-reviewed paper published in the journal is entitled “Multicenter assessment of CSF-phosphorylated tau for the prediction of conversion of MCI” – first author is Michael Ewers, PhD, senior research fellow in Professor Hampel’s team. Published December 11, 2007