Active Travel Mode and Incident Dementia and Brain Structure

Area of Science:

• Neuroscience and Public Health
• Epidemiology of neurodegenerative diseases
• Physical activity and brain health

Background:

• Active travel modes (walking, cycling) are established forms of physical activity.
• The link between active travel, dementia risk, and brain structure is not well understood.
• Genetic predisposition may influence the relationship between travel modes and dementia.

Purpose of the Study:

• To examine the long-term association between travel modes and dementia risk.
• To investigate the relationship between travel modes and brain structural metrics.
• To determine if genetic susceptibility modifies the travel mode-dementia risk association.

Main Methods:

• Prospective cohort study utilizing UK Biobank data (2006-2010).
• Travel modes categorized: nonactive, walking, mixed-walking, cycling, mixed-cycling.
• Dementia incidence (all-cause, YOD, LOD, AD) and brain structure (MRI) assessed.
• Cox proportional hazards regression models used for analysis.

Main Results:

• Cycling/mixed-cycling associated with reduced risk of all-cause dementia (HR 0.81), AD (HR 0.78), YOD (HR 0.60), and LOD (HR 0.83) compared to nonactive travel.
• Active travel linked to increased hippocampal volume (β 0.05).
• Significant interaction between travel mode and APOE ε4 carrier status observed for all-cause dementia and LOD, with lower risks for non-carriers who cycle.

Conclusions:

• Active travel, particularly cycling, is associated with a lower risk of dementia and improved brain structure.
• The protective effect of cycling against dementia may be more pronounced in individuals without the APOE ε4 genetic risk factor.
• Promoting active travel modes like cycling could be a strategy for dementia prevention and maintaining brain health.