Metabolic and cardiovascular adjustments during psychological stress and carotid artery intima-media thickness in youth

Objective: Cardiovascular reactivity is associated with carotid artery intima-media thickness as early as childhood. Excess cardiovascular responses relative to the metabolic demand during psychological stress have been proposed as a mechanism for this association. However, it is not known whether excess cardiovascular responses in relation to the metabolic demand correlate with carotid artery intima-media thickness as strongly as traditionally measured cardiovascular reactivity. Methods: Fifty-four adolescents, ages 13-16. years completed a graded exercise test in 1. day and measures of psychological stress reactivity (star tracing, speech) on another day. Heart rate, systolic blood pressure, and oxygen consumption were measured on both days. On a third visit adolescents completed an ultrasound scan to measure carotid artery intima-media thickness. Results: Traditionally measured systolic blood pressure reactivity (β=0.30, p=0.02, R ² increase=0.09) and excess systolic blood pressure (β=0.30, p=0.02, R ² increase=0.08) while preparing a speech were associated with greater carotid artery intima-media thickness when controlling for demographic characteristics, fitness, and baseline systolic blood pressure. Conclusions: This study adds to the growing body of literature showing a link between systolic blood pressure reactivity to acute psychological stress and carotid artery intima-media thickness in youth. This was the first study to demonstrate that systolic blood pressure in excess of the metabolic demand during psychological stress was also associated with carotid artery-intima media thickness.