Brain changes typical of Alzheimer’s disease may also cause subtle impairments in someone’s ability to walk, according to a new report. The study found that elderly men and women with memory problems who walked slowly were at increased risk of developing Alzheimer’s disease.
“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,” said the study’s lead author, Natalia del Campo, of the University Hospital Toulouse in France.
The findings bolster earlier research showing that gait problems may be linked to Alzheimer’s disease. Slow walking or walking problems have been tied to a variety of problems in the elderly, including an increased risk of falls, illness and dementia, including Alzheimer’s.
The newest study looked at 128 elderly men and women, average age 76, who had memory complaints and were considered at high risk of developing Alzheimer’s disease. Some had been diagnosed with mild cognitive impairment, also called MCI,a form of memory loss that often precedes Alzheimer’s, but none had symptoms of full-blown Alzheimer’s.
The study participants underwent brain scans using positron emission tomography. PET scans can measure the buildup in the brain of beta-amyloid, a toxic protein that forms the telltale brain plaques of Alzheimer’s disease. Almost half of the volunteers had levels of beta-amyloid typical of those with Alzheimer’s.
Participants also underwent tests of memory and thinking skills, as well as tests to measure how well they could carry out day-to-day-tasks. Almost half of the study volunteers were found to have mild cognitive impairment.
The researchers also conducted tests of walking speed. Participants were asked to walk 4 meters, or about 13 feet, at their customary pace. On average, it took them about 42 second to complete that distance – within the normal range.
But, the researchers found, the slowest walkers also tended to have the greatest buildup of beta-amyloid in the brain. They controlled for factors like age, education, and degree of memory problems. Walking speed still correlated closely with beta-amyloid buildup in the brain.
The authors note that their study does not prove that beta-amyloid plaques cause walking speed to diminish. Many health problems can impair the ability to walk, including heart disease, arthritis and other diseases. But the findings do suggest that damage to the brain caused by plaques may cause problems with walking. Researchers plan to conduct further research to explore the links between walking and Alzheimer’s disease.
Source: Natalia del Campo, PhD, Pierre Payoux, MD, PhD, Adel Djilali, PhD, et al: “Relationship of Regional Brain Beta-Amyloid to Gait Speed.” Neurology Vol. 86, pages 1-8, Dec. 2, 2015