A Healthy Mind in a Healthy Body – Association between Level and Change in Physical Fitness and Brain Atrophy Benjamin Aribisala Brain Research Imaging Centre Division of Clinical Neuroscience, University of Edinburgh Co-authors: Alan Gow, Mark Bastin, Maria Valdés Hernández, Natalie Royle, Susana Muñoz Maniega, John Starr, Ian Deary, Joanna Wardlaw

Introduction Better fitness is associated with higher cognitive ability More brain atrophy is associated with poorer cognitive ability The underlying mechanism through which fitness affects cognitive ability in under investigated Cognitive Ability Fitness Brain Atrophy

Aim and Hypotheses Aim Hypotheses To examine the associations between Current physical fitness level and brain atrophy Change in physical fitness level and brain atrophy Hypotheses A higher level of fitness is associated with less brain atrophy Fitness decline over a period of time is associated with greater brain atrophy

Lothian Birth Cohort 1936 Surviving participants of Scottish Mental Survey 1947 N=70, 805 All born in 1936 Nationwide IQ test at age 11, 1947 community dwelling, Lothian area of Scotland Wave 1 (2004 - 2007) N= 1091 Cognitive and Physical Fitness assessment Mean age 70 Wave 2 (2007 - 2010) N= 866 Mean age 73 Brain MR imaging (N=700)

Brain Atrophy Measurements Brain MR, Age 73, 1.5 T GE scanner, T1W, T2W, T2*W, FLAIR Segmentation used MCMxxxVI1 Fuses pairs of MR Images in R/G colour space Enhances visual differences T2W T1W T2*W FLAIR FUSED Volumetric measurements Total Brain Tissue Ventricle CSF Grey Matter Normal Appearing White Matter Intracranial volume 1. Valdes Hernandez et a., Eur. Radiol., 2010, 20(7):1684-91 http://sourceforge.net/projects/bric1936/

Physical Fitness Measurements Grip strength Forced Expiratory Volume 6-meter timed walk measures = Grip strength measures Forced expiratory volume measures Forced Expiratory Volume Grip Strength 6-meter timed walk general Fitness factor 6-meter timed walk All measures Taken at mean ages 70 and 73 Adjusted for height and sex

Results All fitness variables reduced from age 70 to 73 Higher level of fitness was associated with larger brain tissue Similar for ages 70 and 73 No association with Fitness change Values are standardized β Red= Significant, p<0.01

Results Higher level of fitness was associated with smaller ventricle Similar for ages 70 and 73 Similar for CSF No association with Fitness change Values are standardized β Red= Significant, p<0.01

Results Higher level of fitness was associated with larger normal appearing white matter volume Similar for ages 70 and 73 Fitness decline from ages 70 to 73 was associated with smaller NAWM Values are standardized β Red= Significant, p<0.01

Conclusions Hypotheses A higher level of fitness was associated with lower brain atrophy Fitness decline from age 70 to 73 was associated with higher brain atrophy, only for normal appearing white matter Findings support improving fitness levels as an intervention to maintain brain health in later life Future work Will include longitudinal volumetric measurements to assess association between change in fitness level and change in brain volumes Longer time follow up is required to determine the true associations and mechanisms through which fitness might influence brain structure

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