
Changes in Subconscious Movements May Be New Way to Predict Alzheimer’s Disease
Predicting Alzheimer’s before cognitive impairment occurs can be difficult. However, some researchers have taken to studying 24-hour movement in adults to see if it can give any clues to future cognitive issues. A new study has found that changes in subconscious movements may be a good predictor.
A team of researchers from Brigham and Women’s Hospital, the Massachusetts General Hospital, and Washington University at St. Louis have tackled the topic by looking at fractal motor activity regulation, or FMAR. Those are complex fluctuations in movement that occur throughout the day without us giving any thought to them. The team found that in cognitively health adults, there was a link between these movements and women who had an established biomarker for preclinical Alzheimer’s disease. The findings were published in Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring.

Dr. Lei Gao, co-lead author and assistant professor of Anesthesiology at MGH, says, “Our day-to-day movements that are subconscious can reveal changes in the brain that may occur many years before symptoms show. If validated in future studies, this may provide a window of opportunity for early treatments and motivate the modification of existing risk factors.”
To conduct the study, the researchers examined 178 cognitively healthy adults from the Washington University Knight Alzheimer’s Disease Research Center. Participants had their movements tracked at home for seven to 14 days. Pittsburgh Compound B (PiB) PET amyloid imaging was also performed in 150 of the participants, while cerebrospinal fluid (CSF) was taken from 149. Both are biomarkers of preclinical Alzheimer’s.
Researchers found that degradation of FMAR was strongly linked with both markers. This was independent of age, physical activity, fragmented circadian rhythms, and whether or not the participant was a carrier of the Alzheimer’s-associated gene variant APOE-e4. This only applied to women, though, not men.

The findings indicate that FMAR could be a useful Alzheimer’s predictor.
Gao says, “FMAR represents a non-invasive biomarker for testing and screening for AD. In addition, we focused on daytime activity, which removed sleep as a potential confounder. The results also remained after controlling for more established circadian disruption measures; this suggests that FMAR has unique pathways to AD pathology that require further study.”
One limitation of the study was that the group was not very diverse, so they couldn’t make any distinctions for race or ethnicity. There also needs to be further research to validate the findings.
Still, if these findings can be replicated in future studies, it could mean some positive changes for existing Alzheimer’s procedures.
Dr. Kun Hu, co-senior author and physiologist in the Division of Sleep and Circadian Disorders in the Departments of Medicine and Neurology at the Brigham, says, “We’re very excited to see FMAR applied for the early detection of AD. This kind of approach could potentially guide research on AD and allow us to shift from focusing solely on cognition to improving motor functions that may link AD to other disorders, including sleep/circadian disorders.”

Movement changes may also be used to determine other factors related to dementia. Studies have found that it may be possible to determine which type of dementia someone has based on how they walk.