Do hypertensive individuals have enlarged aortic root diameters? Insights from studying the various subtypes of hypertension.
BACKGROUND
Aortic root diameter (AoD) increases with aging and is related to body size. AoD is also presumed to increase in hypertension. In prior studies, however, after adjusting for age and body size, AoD did not differ between hypertensive and normotensive (NT) individuals. Hypertension is a heterogeneous condition with various subtypes that differ in pathophysiology and age distribution. We assessed whether AoD differs among subjects with the various subtypes of hypertension and nonhypertensive individuals.


METHODS
In 1,256 volunteers aged 30-79 years (48% women, 48% hypertensive; all untreated), AoD was measured at the sinuses of Valsalva with transthoracic echocardiography. Using cutoff values based on the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, subjects were identified as NT (23%), or prehypertensive (PH, 29%), or as having isolated diastolic (IDH, 6%), isolated systolic (ISH, 12%), or systolic-diastolic (SDH, 30%) hypertension. Groups were compared using analysis of variance with Bonferroni's correction.


RESULTS
AoD increased with age and body surface area (BSA) in both men (r = 0.25 and 0.19, respectively) and women (r = 0.30 and 0.22, respectively) (all P < 0.0001). In men, those identified as having IDH, ISH, and SDH each had a 6% larger AoD than NT individuals (all P < 0.05). In women, those identified with ISH and SDH had a 10 and 8% larger AoD than NT individuals, respectively (all P < 0.05). In both sexes, after indexing to BSA, only ISH individuals exhibited larger AoD compared with NT individuals (both P < 0.05). But, with further adjustment for age, these differences were no longer observed.


CONCLUSIONS
Even when the subtypes of hypertension are examined separately, age and BSA, not hypertension status, account for the AoD differences between NT and hypertensive subjects.
Farasat
S Morteza
SM
Laboratory of Cardiovascular Science, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA.
Morrell
Christopher H
CH
Scuteri
Angelo
A
Ting
Chih-Tai
CT
C P Yin
Frank
F
Spurgeon
Harold A
HA
Chen
Chen-Huan
CH
G Lakatta
Edward
E
Najjar
Samer S
SS
D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000473:pathology*; D001794:Blood Pressure; D049628:Body Size; D001830:Body Surface Area; D015331:Cohort Studies; D005260:Female; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000145:classification / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012850:Sinus of Valsalva / Q000000981:diagnostic imaging* / Q000503:physiopathology; D013624:Taiwan; D014463:Ultrasonography