Ethnicity, family history of hypertension and patterns of hemodynamic reactivity in boys.

This study compared blood pressure, heart rate, stroke volume, vascular resistance, and cardiac output responses to a video game challenge and forehead cold stressor in 6- to 15-year-old males who varied in ethnicity and family history of essential hypertension. Controlling for age, significant baseline differences were obtained with black boys exhibiting higher systolic and diastolic pressures than their white cohorts. Positive family history children were found to have higher cardiac outputs and stroke volumes indexed by body surface area during baseline. Controlling for baseline hemodynamic responses and age, positive family history children exhibited greater increases in systemic vascular resistance and systolic and diastolic pressure and greater decreases in heart rate to the cold stressor. The positive family history children exhibited greater decreases in cardiac index during both the video game and cold stressor phases. Implications of the findings and directions for future research are discussed.