While the accumulation of proteins in the brain is a marker to indicate the onset of Alzheimer's, a new study analysed the ways in which these proteins spread, that might help in describing why the disease is more prevalent in females than males. 

A recent study presented at the Alzheimer's Association International Conference has identified differences in the spread of a protein called tau, which is linked to cognitive impairment -- between men and women, with women showing a larger brain-wide accumulation of tau than men due to an accelerated brain-wide spread. Accumulating evidence suggests that tau spreads through brain tissue like an infection, traveling from neuron to neuron and turning other proteins into abnormal tangles, subsequently killing brain cells. 

Researchers used data from positron emission tomography (PET) scans of healthy individuals and patients with mild cognitive impairment who were enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. 

"It's kind of like reconstructing a crime scene after a crime. You weren't there when it happened, but you can determine where an intruder entered a house and what room they entered next," said Sepi Shokouhi, lead investigator for the study. "The graph analysis does something similar to show how tau spreads from one region to another," Shokouhi added. 

The findings showed that the architecture of tau networks is different in men and women, with women having a larger number of "bridging regions" that connect various communities in the brain. This difference may allow tau to spread more easily between regions, boosting the speed at which it accumulates and putting women at greater risk for developing Alzheimer's disease. 

The lead study investigator said, "Understanding how different biological processes influence our memory is a really important topic." "Sex-specific differences in the brain's pathological, neuroanatomical and functional organization may map into differences at a neurobehavioral and cognitive level, thus explaining differences in the prevalence of neurodegenerative disorders and helping us develop appropriate treatments," Shokouhi opined.