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

Authors: LAMBIASE, MAYA - University Of Buffalo; DORN, JOAN - University Of Buffalo; Roemmich, James

Submitted to: Physiology & Behavior
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2011
Publication Date: 3/20/2012
Citation: Lambiase, M., Dorn, J., Roemmich, J.N. 2012. Metabolic and cardiovascular adjustments during psychological stress and carotid artery intima-media thickness in youth. Physiology and Behavior. 105(5):1140-1147.

Interpretive Summary: The absolute systolic blood pressure during exercise and the increase in systolic blood pressure above baseline, or reactivity, in systolic blood pressure during psychological stress are correlated with an increased risk for cardiovascular disease. Most studies hypothesize that increased cardiovascular responses to stress contribute to the development of cardiovascular disease. However, the direction of this relationship remains ambiguous. It is unclear if increases in systolic blood pressure during exercise and stress promote the development of cardiovascular disease or if subclinical changes to the vasculature alter cardiovascular changes during exercise and psychological stress. Ultrasound measures of the carotid artery intima-media thickness allow for assessing subclinical alterations in the peripheral vasculature that predict later cardiovascular health. We thought that determining the association of systolic blood pressure reactivity during psychological stress and exercise with ultrasound measured carotid artery intima-media thickness might give insight into this relationship. Fifty-four youth, ages 13-16 years completed three visits. On one day they completed three, 4-minute stages of increasing intensity on a treadmill. On another day, they completed measures of psychological stress reactivity (star tracing, speech preparation, speech). On a third visit they completed an ultrasound scan to measure carotid artery intima-media thickness. We found that systolic blood pressure reactivity during speech preparation (a psychological stressor) significantly added to the prediction of carotid artery intima-media thickness. Systolic blood pressure reactivity during both lower (ß=0.001, p<0.03) and higher intensity exercise also predicted carotid artery intima-media thickness. Thus, systolic blood pressure reactivity during psychological stress and submaximal exercise were both correlated with carotid artery intima-media thickness in healthy adolescents. A general tendency for individuals to be more reactive to a variety of psychological and physical stressors was observed. The magnitude of the reactivity across different stress tasks did not seem to be the main determinant of carotid artery intima-media thickness.

Technical Abstract: Objective: Absolute systolic blood pressure during exercise and a greater increase above baseline, or reactivity, in systolic blood pressure during psychological stress are correlated with an increased risk for cardiovascular disease. Most studies hypothesize that increased cardiovascular responses to stress contributes to the development of cardiovascular disease. However, the direction of this relationship remains ambiguous. Determining the association of systolic blood pressure reactivity during psychological stress and exercise with ultrasound measured carotid artery intima-media thickness might give insight into this relationship. Methods: Fifty-four adolescents, ages 13-16 years completed three visits. On one day adolescents completed three, 4-minute stages of increasing intensity on a treadmill. On another day, in counterbalanced order, adolescents completed measures of psychological stress reactivity (star tracing, speech preparation, speech). On a third visit adolescents completed an ultrasound scan to measure carotid artery intima-media thickness. Results: Systolic blood pressure reactivity during speech preparation significantly added to the prediction of carotid artery intima-media thickness (ß=0.001, p<0.05). Systolic blood pressure reactivity during lower (ß=0.001, p<0.03) and higher (ß=0.001, p<0.02) intensity exercise also predicted carotid artery intima-media thickness. Conclusions: Systolic blood pressure reactivity during psychological stress and submaximal exercise were correlated with carotid artery intima-media thickness in healthy adolescents. A general tendency for individuals to be more reactive to a variety of stressors was observed. The magnitude of the reactivity across different stress tasks did not seem to be the main determinant of carotid artery intima-media thickness.