Grant: Travel Awards - Institute Community Support

Alzheimer's disease (AD) and subcortical ischemic vascular cognitive impairment (SIVCI) are the two most common causes of cognitive impairment and often people present with mixed AD-SIVCI pathology. Alzheimer's disease is a neurodegenerative disease characterized by the presence of amyloid plaques and neurofibrillary tangles and SIVCI is predominantly caused by small vessel ischemia resulting in white matter lesions and lacunar infarcts. Currently, much of our knowledge on the effects of co-existing amyloid pathology in SIVCI are based on cross-sectional studies and little is known about their effects on changes in cognitive and physical function over time. Thus, the objective of this study was to assess the impact of amyloid pathology on global cognition, executive functions, and physical function over a 12-month period in people with SIVCI. This was a planned secondary analysis of data acquired from a proof-of-concept randomized controlled trial of aerobic activity in people with SIVCI. A hierarchical multiple linear regression analysis was conducted to determine the unique contribution of amyloid pathology on cognitive/physical function after controlling for age, experimental group, and baseline cognitive/physical performance. We found that amyloid pathology significantly predicted decreased performance in: 1) Attention; 2) Set shifting; 3) Processing speed and; 4) Falls risk. However, amyloid pathology did not predict changes in global cognition or working memory. Our study suggests that amyloid pathology might be a marker for future decline in cognitive and physical performance among older adults with a primary SIVCI diagnosis.