Simple Tests May Flag Dementia, Stroke Risk

Published on: February 15, 2012

by Charles Bankhead for Medpage Today:

Walking speed and hand-grip strength during middle age correlated with cognitive function and stroke risk in older adults, suggesting simple tests might aid diagnosis of the two conditions, according to data from a large cohort study.

During 11 years of follow-up, slower walking speed at baseline was associated with a 50% rise in the hazard for dementia. Brain volume and performance on a variety of tests of cognitive function also were significantly lower in slower walkers.

Grip strength did not influence stroke risk in the overall cohort, but a higher baseline grip strength was associated with a 42% reduction in stroke risk among individuals 65 and older, as will be reported here in April at the American Academy of Neurology meeting.

“These are basic office tests [that] can provide insight into the risk of dementia and stroke and can be easily performed by a neurologist or general practitioner,” Erica C. Camargo, MD, PhD, of Boston Medical Center, said in a statement.

“While frailty and lower physical performance in elderly people have been associated with an increased risk of dementia, we weren’t sure until now how it impacted people of middle age,” she added.

The findings came from an analysis of data from the Framingham Offspring Cohort, children of the original participants in the long-running study of the natural history of cardiovascular disease.

Camargo and colleagues analyzed data for 2,410 participants in the offspring cohort study, mean age 62, all of whom were stroke- and dementia-free at baseline. The initial workup included assessments of walking speed, grip strength, and cognitive function, as well as MRI scans of the brain.

The investigators statistically related age-standardized grip strength and walking speed with baseline cerebral volume estimated by MRI, with age- and education-standardized cognitive function and with stroke and dementia incidence.

During follow-up, 34 participants developed dementia, and 79 had strokes or transient ischemic attacks (TIAs). Slower walking speed had a significant correlation with:

• Increased stroke risk (HR 1.50, P=0.020)
• Lower total cerebral volume (P=0.007)
• Poorer performance on tests of various aspects of memory (visual reproduction, P=0.009; paired associate learning, P<0.001; executive function, P=0.004; visuo-perceptual function, P=0.002; and language, P=0.006)

Greater hand-grip strength was associated with a significant reduction in stroke risk (HR 0.58,P=0.013) in the subgroup of 784 participants who were older than 65 at baseline.

Increasing grip strength also was associated with:

• Total cerebral brain volume (P<0.001)
• Visual reproduction (P<0.001)
• Executive function (P=0.009)
• Visuo-perceptional function (P<0.001)
• Language (P=0.002)
• Better abstraction (P=0.009)

Acknowledging the need for more studies, Camargo and colleagues concluded that “walking speed and hand-grip strength might serve as clinical markers of the need for a more detailed assessment of brain function.”