Researchers develop tool to predict one's risk of developing Alzheimer's

Researchers have created a new tool — a prediction model — for estimating one's risk of developing memory and thinking problems, usually associated with an onset of Alzheimer's disease, up to 10 years before symptoms may appear.

Women could be at a higher risk over a lifetime of developing the neurodegenerative condition or mild cognitive impairment, which is considered to precede Alzheimer's disease, said the team from Mayo Clinic, a US-based integrated, not-for-profit medical group practice.

Alzheimer's disease is an ageing-related disorder in which memory, speech and thought processes steadily decline and can eventually affect one's daily functioning.

Men and women with a common genetic variant — 'APOE e4' — also have higher lifetime risk, the researchers said.

Published in The Lancet Neurology journal, the study analysed data from 5,858 participants and builds on decades of information, including brain scans, collected via the 'Mayo Clinic Study of Aging' project.

"In this retrospective, longitudinal cohort study of data from participants of the population-based Mayo Clinic Study of Aging (Olmsted County, Minnesota, USA), we computed lifetime and 10-year absolute risk of cognitive impairment in participants who were cognitively unimpaired and aged 50 years or older at enrolment," the authors wrote.

The tool combined factors, including age, gender, genetic risk and amyloid levels in the brain —considered a hallmark of Alzheimer's disease — detected in PET scans (positron emission tomography) to estimate an individual's risk of developing mild cognitive impairment or dementia within 10 years or one's predicted lifetime.

Amyloid levels, in which proteins in the brain accumulate to form clumps, detected using PET scans were noted to be the strongest predictor for lifetime risk of developing mild cognitive impairment or dementia.

Co-author Ronald Petersen, neurologist and director of Mayo Clinic Study of Aging, said, "This kind of risk estimate could eventually help people and their doctors decide when to begin therapy or make lifestyle changes that may delay the onset of symptoms. It's similar to how cholesterol levels help predict heart attack risk."

While the risk prediction tool is currently a research instrument, it represents a major step towards a more personalised care, with future versions possibly looking at blood-based biomarkers, the researchers said.