THE CARDIOVASCULAR-RESPONSE TO POSTURAL CHANGE AS A FUNCTION OF RACE

Little is known about racial differences in cardiovascular responses t o postural change. The immediate and delayed change from sitting to st anding was studied in 207 healthy young Asian, black, and white men an d women by means of a noninvasive blood pressure tracking system. Wher eas Asians and whites had decreased mean arterial pressure (MAP) 32-41 s after standing, blacks had an increase. During the delayed response (3 min after standing), compared to Asians and whites, blacks had gre ater increases in diastolic blood pressure and MAP. Their heart rate i ncrease was also greater than Asians. For systolic blood pressure and pulse pressure there were Race X Family History interactions for the i mmediate response to orthostasis and Race X Gender interactions for th e delayed response. Blacks generally displayed different cardiovascula r patterns from the other two racial groups, possibly reflecting incre ased peripheral resistance and altered baroreceptor function.