The speed of how older adults walk may be an indicative of an Alzheimer's (AD) risk, a new study found. This may provide a reliable hint of how well their brain is aging.
Researchers led by Dr. Natalia del Campo of the Gerontopole and the Centre of Excellence in Neurodegeneration of Toulouse, in France, found that the pace of the elderly in terms of walking may be related to the amount of amyloid that have built up in their brains despite not having any signs or manifestations of AD.
Amyloid precursor protein (APP) or amyloid beta (A4) precursor protein is found throughout the body especially in the central nervous system (CNS). Though its specific function is not clear, scientists speculate that it may bind to other proteins and help cells attach to each other. In the CNS specifically, it is known to help direct the migration of nerve cells during early development.
Its involvement in Alzheimer's disease is known to be linked with APP gene mutation changes. When this happens, there is increased production of APP or sometimes, APP becomes too sticky that when the cells release them, they accumulate in the brain and form clumps called amyloid plaques.
In the study published [pdf] in Neurology, the medical journal of the American Academy of Neurology, 128 people who have no history of dementia and were considered at high risk of developing the brain degenerative disease due to memory lapses were enrolled. Using positron emission tomography (PET) scan, the researchers measured the amount of amyloid plaques in the participants' brains.
Findings show that 48 percent of the participants showed levels of amyloid indicative of dementia. Aside from brain scans, they underwent cognitive, memory and assessment of daily activity tasks. A total of 46 percent of the participants have mild cognitive impairment and this may signal the beginning of dementia.
Aside from these tests, a walking assessment was also initiated. The test involves measuring the amount of time and speed they can walk about 13 feet at their normal pace. They found that the average walking speed was 3.48 feet per second. However, two participants fell short in the test while the others walked the distance in a normal speed.
When all tests were collated, the researchers found a link between slow walking speed and amyloid deposits in various areas in the brain specifically the putamen, a region associated with motor function.
"It's possible that having subtle walking disturbances in addition to memory concerns may signal Alzheimer's disease, even before people show any clinical symptoms," Dr. del Campo said.
Alzheimer's disease is now the 6th leading cause of death in the United States and it is the only disease included in the top 10 leading causes of mortality that cannot be prevented or cured. Around 5.3 million Americans have AD in 2015.
Photo: Garry Knight | Flickr