Researchers are applying standardised criteria to international studies of centenarians to better understand the prevalence and incidence of rates of dementia in this group, as well as risk and protective factors for dementia and healthy brain ageing across the lifespan. The Centre for Healthy Brain Ageing (CHeBA) at UNSW is leading the research through the International Centenarian Consortium-Dementia (ICC-Dementia), which seeks to create comparable data across countries and study sites to improve the statistical significance of findings and explore universal factors and regional differences.
Lead author and Co-Director of CHeBA Professor Henry Brodaty, published a protocol paper in this month’s issue of BMC Neurology outlining the aims and structure of the consortium, selection criteria for participating studies, and a summary of planned harmonisation and statistical procedures.
Rates of dementia incidence and prevalence among centenarians, or people aged 100 years and over, are still not well studied despite the potential this group has in providing unique insights into the risk and protective factors for dementia, explained the other lead author and Co-Director of CheBA, Professor Perminder Sachdev.
“We know that there is a 20 to 30 year delay between the beginning of the disease process and symptoms becoming apparent, with rates of dementia increasing exponentially after the age of 65. Examining rates of dementia in the oldest members of society will give us important insights into the disease process, particularly around risk and protective factors, since these individuals may provide real-life models of healthy brain ageing,” said Professor Brodaty.
According to co-author on the paper and Study Co-ordinator of ICC-Dementia at CHeBA, Catriona Daly, establishing standardised criteria for diagnosing dementia in this special group is the first step in this process.
“Enabling comparison between large scale studies from around the world, provides more statistically robust findings and allows us to investigate regional and ethnic differences, which cannot be understood from individual cohort studies alone,” said Ms Daly.
Combining seventeen different centenarian and near-centenarian studies from Asia, Europe, the Americas, and Oceania, ICC-Dementia seeks to harmonise these studies internationally to describe the cognitive and functional profiles of exceptionally old individuals and systematically explore the factors involved in dementia and longevity. It is one of four consortia contributing to The Dementia Momentum, an initiative of CHeBA which is harnessing the power of 'big data' to better understand and thereby reduce dementia incidence.