P2‐297: Aerobic Exercise Increases Cortical White Matter Volume in Older Adults with Vascular Cognitive Impairment: A 6‐month Randomized Controlled Trial

Worldwide, Sub-cortical vascular ischaemia (SVCI) is the second most common etiology contributing to cognitive impairment among older adults. Yet, SVCI may be the most treatable form of cognitive impairment as many of its risk factors can be reduced with exercise. Nevertheless, few randomized controlled trials to date have specifically assessed the efficacy of exercise training on cognitive and brain outcomes in this high-risk group. Thus, we conducted a 6-month proof-of-concept randomized controlled trial of thrice-weekly aerobic exercise training (AE) among adults with mild SVCI. A sub-set of participants underwent MRI scanning; the focus of this analysis was to investigate the effect of AE on both white matter and grey matter in this sub-set. Seventy-one adults (56-96 years) with SVCI were recruited and randomized (1:1) to one of two experimental groups: 1) 3x/week AE or 2) usual care (UC). SVCI was confirmed by: 1) evidence of subcortical white matter lesions from neuroimaging (i.e., CT or MRI); 2) a score of less than 26 on the Montreal Cognitive Assessment (MoCA); and 3) clinical assessment by neurologist. Thirty participants (16 from AE and 14 from UC) completed 3T MRI scanning both at baseline and trial completion. Scans were analyzed using FSL Freesurfer. Compared with the control group, cortical white matter volume significantly increased in the AE group (p = .039). However, total grey matter volume significantly decreased in the AE group compared with the UC group (p= .043). A 6-month AE program significantly increased white matter volume in older adults diagnosed with VCI compared with the control group. However, future studies are need to confirm our current results.