Cognitive processing speed mediates the effects of cardiovascular disease on executive functioning

Area of Science:

• Neuroscience
• Gerontology
• Cardiology

Background:

• Cardiovascular disease (CVD) is prevalent in older adults.
• Executive functioning (EF) and cognitive processing speed (CPS) often decline with age.
• The relationship between CVD, CPS, and EF requires further investigation.

Purpose of the Study:

• To examine the mediating role of cognitive processing speed (CPS) in the relationship between cardiovascular disease (CVD) and executive functioning (EF).
• To determine if the processing-speed hypothesis explains EF deficits in older adults with CVD.

Main Methods:

• Neuropsychological assessments of CPS and EF were administered to older adults with and without a history of CVD.
• Structural equation modeling was used to analyze indirect associations between CVD, CPS, and EF outcomes.
• Product-of-coefficients approach with bias-corrected bootstrap confidence intervals assessed indirect links.

Main Results:

• CVD was negatively associated with CPS (β = -.239) and EF (β = -.137).
• CPS was positively associated with EF (β = .566).
• Indirect links from CVD to EF via CPS were significant, particularly for cognitive flexibility and inhibition tasks.

Conclusions:

• The processing-speed hypothesis extends to older adults with CVD.
• Reduced CPS significantly mediates the link between CVD and poorer EF.
• CPS is a CVD-related mechanism contributing to executive dysfunction in older adults.