Progression pattern of brain mineral deposition as a differential indicator of cognitive decline

Using MRI data available from the ADNI-2 database, this project examined basal ganglia mineral deposition (BGMD) and microbleeds in individuals with normal cognitive status (CN), early/late mild cognitive impairment (EMCI/LMCI) and AD in order to assess the role of these features in disease progression. Microbleed count was significantly lower in CN compared to EMCI (p=0.017) and LMCI patients (p=0.002) in the larger of two samples. There was no significant difference in number of microbleeds between CN and AD patients (p=0.416). Median volume of BGMD increased in EMCI patients from year 1-3 and decreased in LMCI patients. Predominantly iron deposition followed the same pattern. Volume of mineralised clusters increased in EMCI with no clear pattern in LMCI or CN individuals. The pattern was replicated in the larger sample with reduced volumes in AD. The results show that microbleeds and BGMD may be useful indicators of Mild Cognitive Impairment (MCI). The trend of increased BGMD load from CN to MCI and decreased load in AD could be used as a differential indicator in AD if replicated in a larger sample.