Linking objective measures of physical activity and capability with brain structure in healthy community dwelling older adults

Abstract

Maintaining high levels of daily activity and physical capability have been proposed as important constituents to promote healthy brain and cognitive aging. Studies investigating the associations between brain health and physical activity in late life have, however, mainly been based on self-reported data or measures designed for clinical populations. In the current study, we examined cross-sectional associations between physical activity, recorded by an ankle-positioned accelerometer for seven days, physical capability (grip strength, postural control, and walking speed), and neuroimaging based surrogate markers of brain health in 122 healthy older adults aged 65-88 years. We used a multimodal brain imaging approach offering two complementary structural MRI based indicators of brain health: white matter diffusivity and coherence based on diffusion tensor imaging and subcortical and global brain age based on brain morphology inferred from T1-weighted MRI data. The analyses revealed a significant association between global white matter fractional anisotropy (FA) and walking speed, indicating higher white matter coherence in people with higher pace. We also found a significant interaction between sex and brain age on number of daily steps, indicating younger-appearing brains in more physically active women, with no significant associations among men. These results provide insight into the intricate associations between different measures of brain and physical health in old age, and corroborate established public health advice promoting physical activity.

Cardiometabolic risk factors associated with brain age and accelerated brain ageing

“…While BAG shows substantial heritability (Cole et al, 2017; Kaufmann et al, 2019), the rate of brain ageing is malleable and dependent on a range of life events and health and lifestyle factors (Cole, 2020; Lindenberger, 2014; Sanders et al, 2021). Understanding the impact of cardiometabolic risk on brain integrity and ageing represents a window of opportunity wherein interventions targeting key elements of cardiometabolic health may delay and even prevent pathological brain changes (Friedman et al, 2014).…”

Dissecting unique and common variance across body and brain health indicators using age prediction

“…Furthermore, individual differences in cognitive reserve (Stern, 2009(Stern, , 2012, or resilience to neuropathological changes typically associated with ageing, could influence differences in age-prediction scores. Future studies might therefore aim to investigate these difference scores in the context of cognitive functions known to change with age, such as memory and reaction time (Grady, 2012), as well as reserve-related mechanisms including education, socioeconomic status, and lifestyle (Anatürk et al, 2021) Previous studies have demonstrated that variation in predicted brain age is partly explained by individual differences in body composition and health traits, including abdominal fat (Beck, de Lange, Pedersen, et al, 2022;Schindler et al, 2022;Subramaniapillai et al, 2022), muscle-fat infiltration (Beck, de Lange, Alnaes, et al, 2022), hand-grip strength (Cole et al, 2018;Sanders et al, 2021) and muscle volume (Beck, de Lange, Alnaes, et al, 2022). Our findings support these previous reports, but also suggest that health traits may differentially influence age predictions beyond what is captured by the brain imaging measures.…”

Assessing the interaction effects of brain structure longitudinal changes and life environmental factors on depression and anxiety

“…Except women, interactions between physical activity and several brain structures were correlated with both depression and anxiety in men. Physical activity and daily exercise are regarded as essential components for maintaining the brain health and cognition function (Sanders et al, 2021). Casaletto et al (2020) found that males exhibited a tighter relationship between daily physical activity and larger parahippocampal volumes, and better visual memory as well as processing speed, whereas these effects seemed to be attenuated or absent in females.…”