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

ABSTRACT

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 (ß=0.30, p=0.02, R(2) increase=0.09) and excess systolic blood pressure (ß=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.