Consistency of hemodynamic responses to cold stress in adolescents

Laboratory research on hypertension often is performed with cold stress to elicit vasoconstriction and increases in blood pressure. Several studies ha ve shown that cardiovascular responses to the cold presser test predict the development of hypertension. We extended this research by comparing cardio vascular responses to a traditional forehead cold presser test and a natura listic whole-body cold exposure. We evaluated blood pressure and impedance cardiographic measures of cardiac output and total peripheral resistance in healthy black (n = 69) and white (n = 47) adolescents (mean age, 14.7 year s) during forehead cold presser (3 degreesC to 4 degreesC) and passive whol e-body exposure to a cold chamber (8 degreesC to 10 degreesC). Both tasks e licited increases in vascular resistance and blood pressure, but forehead c old elicited an increase in cardiac output, whereas whole-body cold elicite d a decrease in cardiac output (P < 0.05). Consistent with previous researc h, there was a tendency toward greater vasoconstrictive reactivity to cold stress in blacks than in whites, particularly during whole-body cold exposu re (P < 0.05). Cardiovascular reactivity correlated significantly between t asks, but substantial intertask consistency occurred only for cardiac and v ascular reactivity in male subjects (r > 0.30) but not in female subjects ( r < 0.15). These gender differences might reflect diminished adrenergic rec eptor function in female subjects. We conclude that whole-body cold exposur e offers a viable, relatively naturalistic alternative to traditional cold presser tests for the assessment of cardiovascular reactivity.