Andrea Rosso thinks, in the future, doctors who work with older adults will regularly time them walking down hallways. But it won’t be to find out if they’re slowing down for physical reasons; it will be to determine if they are in the early stages of cognitive disorders such as Alzheimer’s and dementia.
Scientists have known for about five years that slower walking speeds are linked to cognitive decline. Now researchers at the University of Pittsburgh are starting to figure out why, and they believe that the connection lies in a region of the brain called the right hippocampus.
Rosso, an epidemiologist with Pitt’s Graduate School of Public Health, said the hippocampus plays an important role in the development of memory.
“We also are starting to realize it’s involved in spatial navigation and spatial memory, which may be the reason why it’s also related to gait speed,” Rosso said.
Rosso and her colleagues monitored the gait speed and cognitive skills of 175 older adults over the course of 14 years. During the study, all of the participants slowed when asked to walk an 18-foot stretch of hallway. Participants also underwent cognitive testing to see how well their short-term memory was functioning and how well they could process information.
Those who slowed at least one-tenth of a second more than their peers were 47 percent more likely to develop cognitive impairment.
Those results only reinforced what scientists already knew, Rosso said. MRI scans further pinpointed the hippocampus as the possible locus for both physical and mental slowing in older age.
It was the only region of the brain that shrunk in correlation with both slowing gait and cognitive decline, Rosso said.
“Typically if we see, in older adults, slowing, we think of mechanical issues, but this will point physicians towards thinking about whether or not there’s a neurologic contributor to their slowing gait,” she said.
Rosso’s paper is published in the journal Neurology.