Neurobiological Pathways Linking Acute Mental Stress to Impairments in Executive Function in Individuals with Coronary Artery Disease

BACKGROUND: Individuals with coronary artery disease (CAD) have worse executive function compared to the general population but the mechanisms are unknown. OBJECTIVE: To investigate the role of acute mental stress (MS) on the executive function of patients with CAD. METHODS: Participants with stable CAD underwent acute MS testing with simultaneous peripheral vascular function measurements and brain imaging using high resolution-positron emission tomography. Digital pulse wave amplitude was continuously measured using peripheral artery tonometry (PAT, Itamar Inc). Stress/rest PAT ratio (sPAT) of pulse wave amplitude during MS/baseline was calculated as a measure of microvascular constriction during MS. Plasma levels of catecholamine and interleukin-6 were assessed at baseline and after MS. Executive function was assessed both at baseline and at 2 years follow-up using the Trail Making Test parts A and B. RESULTS: We studied 389 individuals with brain data available for 148 participants. Of this population follow-up cognitive assessments were performed in 226 individuals (121 with brain imaging). After multivariable adjustment for baseline demographics, risk factors, and medication use, a lower sPAT, indicating greater vasoconstriction, a higher inferior frontal lobe activation with MS, and increases in norepinephrine and IL-6 levels with MS were all independently associated with greater time to complete Trail B test.-38.4pt. CONCLUSION: In response to acute MS, greater peripheral vasoconstriction, higher inferior frontal lobe brain activation, and increases in the levels of norepinephrine and IL-6 are associated with worse executive function.