Stress-induced cardiovascular reactivity and atherogenesis in adolescents

Objective: To examine the association between cardiovascular reactivity to a set of psychological stressors and carotid artery intima-media thickness, a marker of subclinical cardiovascular disease in healthy adolescents. Methods: Participants were 25 boys and 23 girls age 14.2±0.9 years who were measured for heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure reactivity to mirror-tracing, reaction time, speech preparation and ad lib speech tasks and for common carotid artery intima-media thickness. Sequential regression analyses were used to establish the incremental increase in R² (Rinc2) for the prediction of intima-media thickness due to cardiovascular reactivity independent of age, BMI percentile, sex, socioeconomic status, and resting HR or BP. Results: SBP reactivity while preparing (β= 0.0019, Rinc2=0.09) and giving the speech (β= 0.0014, Rinc2=0.10) and an aggregate reactivity score based on all 4 tasks (β= 0.0026, Rinc2=0.11) independently predicted (p≤ 0.05) mean carotid artery intima-media thickness. Neither DBP reactivity nor HR reactivity during any task were independent predictors of intima-media thickness. Conclusion: Stress-induced cardiovascular reactivity, and especially SBP reactivity, is associated with carotid intima-media thickness and the early pathogenesis of cardiovascular disease. The use of an aggregate stress reactivity index provides a more reliable reflection of trait SBP reactivity to psychological stress and increases the confidence that youth with greater cardiovascular stress reactivity may indeed have greater progression of subclinical cardiovascular disease.