Research led by researchers within the Neuroimaging Group UNSW Sydney's Centre for Healthy Brain Ageing (CHeBA) has found that specific subregions within the hippocampus may be key in understanding Alzheimer's disease.
The hippocampus is one of the regions in the brain that has been frequently used in the diagnosis of Alzheimer's disease - the most common type of dementia - with hippocampal volume an important biomarker of the disease. Genetic risk of Alzheimer's disease is also indicated by hippocampal atrophy.
However, its structure is not uniform and is actually separated into subregions. These subregions have been observed to be influenced by genetics as well as age and sex.
Heidi Foo, Lead Author and PhD Candidate
The research, published in Neurobiology of Aging, examined the factors which influence the subregions of the hippocampus in 17,161 cognitively normal United Kingdom community dwelling participants aged between 44 and 80 years old.
Associate Professor Wei Wen, Leader of CHeBA's Neuroimaging Group said that the subfields of the hippocampus and their association to Alzheimer's disease have been inadequately investigated.
We found that increasing age and a higher genetic risk score for Alzheimer's disease were associated with decreasing volumes in the subregions. Females also had smaller volumes than males.
Associate Professor Wei Wen
Findings suggested that older individuals showed greater vulnerability to higher Alzheimer's disease genetic risk compared to younger individuals.
"The pattern of decline in the subregions in relation to the genetic predisposition in community dwelling healthy individuals may shed light on the pathogenesis of Alzheimer's disease," said Ms Foo.
Co-Director of CHeBA, Professor Perminder Sachdev, said that increasing our understanding of the hippocampus and its various subregions may be vital in advancing diagnosis and earlier intervention of Alzheimer's disease.
