Previous work has confirmed the benefits of aerobic exercise for brain aging, however mechanisms underlying these effects remain unclear. Two measures of exercise, time spent in moderate-to-vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF), may reflect different pathways linking activity to brain health. Using data from the UK Biobank, the largest sample combining neuroimaging and objectively measured MVPA available to date (n=7148, nmale=3062, nfemale=4086; age=62.14 +/- 7.40 years), we found that, when adjusted for covariates including MVPA, CRF was positively associated with overall gray matter volume (FDR p=1.28E-05). In contrast, when adjusted for covariates including CRF, MVPA was positively associated with left and right hippocampal (FDR pleft=0.01; FDR pright=0.02) volumes, but not overall gray matter volume. Both CRF and MVPA were inversely associated with white matter hyperintensity lesion loads (FDR pCRF=0.002; pMVPA=0.02). Our results suggest separable effects of engagement in exercise behaviors (MVPA) and the physiological effects of exercise (CRF) on structural brain volumes, which may have implications for differential pathways linking exercise and brain benefits.
The genetic basis for Alzheimer?s and neurodegenerative disease ? understanding etiology and interaction with other risk factors.
The aim of the proposed research is to examine how lifestyle factors such as physical activity may interact with genetic risk factors to increase susceptibility to Alzheimer?s disease (AD) and related measures of cognitive decline such as dementia and mild cognitive impairment. We will also attempt to gain a better understanding of the etiology of AD by examining the genetic overlap of AD with other diseases and traits, such as insulin resistance and cardiovascular biomarkers. The main health conditions under investigation are thus AD and cognitive decline. With an aging population and longer lifespans, AD is becoming a major public health concern. Identifying the genetic and lifestyle factors underlying this disease is an important step towards improved prediction, prevention, and treatment. We will be looking for links among genetic variants, lifestyle factors, family history, biomarkers, AD, and measures of cognitive decline. We will consider all genetic variants that are available, and we will also focus on previously established/known genetic markers. We will look for genetic variants and lifestyle factors that are associated with AD, then examine how the effect of genetic factors is modified by lifestyle factors and vice-versa. We will use standard statistical procedures such as linear and logistic regression, as well as multivariate regression. We would like to use the full cohort.
|Lead investigator:||Dr Yann Klimentidis|
|Lead institution:||University of Arizona|
|2147||Differential associations of engagement in physical activity and estimated cardiorespiratory fitness with brain volume in middle-aged to older adults||Raichlen, D.A. et al||2019||Brain Imaging and Behavior. 2019|