Physical activity moderates the association between white matter hyperintensity burden and cognitive change

Area of Science:

• Neuroscience
• Gerontology
• Public Health

Background:

• Cognitive decline is a growing concern in aging populations.
• White matter hyperintensities (WMH) are associated with accelerated cognitive decline.
• The role of physical activity (PA) in mitigating brain pathology effects on cognition is not fully understood.

Purpose of the Study:

• To investigate if physical activity (PA) moderates the relationship between white matter hyperintensity (WMH) burden and cognitive change over five years.
• To explore the potential of PA in preserving cognitive functions despite the presence of WMH.

Main Methods:

• A population-based longitudinal study of 198 dementia-free adults (aged 20-80).
• Assessment of leisure-time physical activity (LTPA) and occupational physical activity (OPA) to calculate total physical activity (TPA).
• Evaluation of 5-year changes in global cognition, reasoning, processing speed, memory, and vocabulary using multivariable linear regression.

Main Results:

• Cognitive functions including reasoning, processing speed, and vocabulary showed significant changes over five years.
• Higher WMH burden correlated with greater decline in global cognition, reasoning, and processing speed, and less vocabulary increase.
• Increased total physical activity (TPA) significantly attenuated the negative association between WMH burden and changes in reasoning, processing speed, and vocabulary, with OPA showing a stronger moderating effect.

Conclusions:

• Physical activity, particularly occupational PA, may preserve reasoning, processing speed, and vocabulary in individuals with white matter hyperintensities.
• Physical activity demonstrates potential for building cognitive reserve and should be further examined as a protective factor against age-related cognitive decline.