Borderline Hypertension andObesity: TwoPrehypertensive States withElevated Cardiac Output

SUMMARY Systemic,renalandsplanchnichemodynamics,intravascularvolume,circulatingcatechola-minelevels andplasmarenin activity were compared in 39patients with borderline hypertension and28normotensivesubjects, who were less than5%(n = 42, leanpatients) ormore than40%overweight(n = 25,obesepatients). Leanborderlinehypertensivepatientshadgreatercardiacoutput(p < 0.05),heartrate(p < 0.01) andrenal bloodflow (p < 0.05); cardiopulmonaryredistribution ofintravascular volume(p < 0.05);andhighercirculatingnorepinephrinelevels (p < 0.05). Obesenormotensivesubjectsalsoshowed an increasedcardiacoutput(p < 0.005),strokevolume(p < 0.01), leftventricularstrokework(p < 0.05), andrenalbloodflow(p < 0.05)(butnotrespectiveindexes), butintravascularvolume was expanded(p < 0.05)without redistribution andcirculating catecholamine levels were normal. Obeseborderline hypertensivepatients hadhemodynamic characteristics similar to those ofobese normotensive subjects except for an increased peripheral resistance (p