How cardio risk impacts cognitive ageing

Dec 15 2016

Functional Neuroimaging Laboratory group

New research at the University of Newcastle’s Functional Neuroimaging Laboratory indicates that cardiovascular health can significantly impact cognitive function in older adults.

When researchers began exploring how the overall health of the brain influences functionality, they noticed some intriguing patterns in their data. The outcomes were published recently in the international neuroscience journal Human Brain Mapping.

“We found that older people who have one or more cardiovascular risk factors showed greater decline in brain white matter health and more cognitive decline than those without. So cognitive decline depends on brain health, not age per se,” group leader Associate Professor Frini Karayanidis says.

In a series of projects encompassing the PhD research of Dr Todd Jolly, researchers explored the relationship between blood flow, cognitive changes and white matter.

“Initially we set out to examine the link between white matter hyperintensities – a sort of neural scar tissue – and their link to cardiovascular health,” explains Patrick Cooper, a co-author on the published study.

“But these lesions weren't as clearly linked to cognitive decline as we had thought. It turns out that it’s the health of the white matter they’re embedded within that has a more important role, and that itself is influenced by cardiovascular risk factors.”

Study participants underwent an MRI brain scan and cognitive challenges, and their cardiovascular risk factors were assessed. Like previous studies, the data showed that mental task-switching capacity decreased with age, but when the researchers controlled for white matter health the effect of age on cognitive capacity disappeared.

“What our studies show is that white matter health can explain the relationship between ageing and cognitive decline, and that this is especially evident in people who have one or more cardiovascular risk factors,” Mr Cooper explains.

The good news, Associate Professor Karayanidis adds, is that some cardiovascular risks are modifiable. “Taking care of your body means taking care of your mind too,” she says. “It’s not age, but how healthy your brain is. It’s a positive message.”

The group is extending this work in people who have had a transient ischemic attack (TIA) to examine the link between severity of cardiovascular risk factors and cognitive decline.

“TIA is like a mini-stroke. These people have an increased cardiovascular burden so we want to replicate the findings in this group,” Mr Cooper says. “We will examine whether effectively controlled cardiovascular risk factors removes the burden on white matter health and cognition.”

* The study was supported by HMRI and the Australian Research Council. HMRI is a partnership between the University of Newcastle, Hunter New England Health and the community.

Video and photo by Eddie O'Reilly, UON Research Services