HYPERTENSION PHENOTYPES BASED ON BRACHIAL AND AORTIC 24HR SYSTOLIC PRESSURE AND THEIR ASSOCIATION WITH HYPERTENSION PHENOTYPES BASED ON BOTH BRACHIAL AND AORTIC 24HR SYSTOLIC PRESSURE AND THEIR ASSOCIATION WITH LEFT VENTRICULAR HYPERTROPHY: FINDINGS FROM THE I24ABC CONSORTIUM

Objective:
To describe the prevalence of systolic hypertension phenotypes based on simultaneous 24hr ambulatory blood pressure monitoring (ABPM) of the brachial (br) and aortic (ao) systolic pressure, as well as their association with left ventricular hypertrophy (LVH), using data from the international 24hr aortic blood pressure consortium (i24ABC).

Design and method:
Participants with 24hr br & ao ABPM (Mobil-O-Graph, IEM Germany) and echocardiography data from 21 centers worldwide were analyzed and categorized into the following 4 phenotypes: sustained [br & ao] systolic normotension (SSN), isolated br systolic hypertension (IbrSH), isolated ao systolic hypertension (IaoSH), and sustained [br & ao] systolic hypertension (SSH). These phenotypes were generated using 2 different calibration (C) methods and various proposed 24hr ao systolic pressure cut-off values (mmHg) (C1: systolic /diastolic pressure [120 and 114]; C2: mean/diastolic [135 and 132]).

Results:
We analysed 2367 individuals (49.5 ± 16.1 years, 54.5% men, 55.8% hypertensives). Depending on both cut-off values as well as on calibration method the phenotypes prevalence ranged: IaoSH 5.8% - 24.2%; IbrSH: 0.2% - 8.7%; SSN: 41.9% - 60.3%; SSH: 29.2% - 33.9%. In comparison to the SSN and after adjustment for age, sex and diastolic blood pressure: the SSH phenotype had 2.4 to 3.2 times more often LVH (statistically significant irrespectively of calibration and cut-off); the IaoSH had 1.7 to 2.4 times more often LVH (statistically significant with both C1 and C2); the IbrSH had 2.1 times more often LVH only with C1 and 120 mmHg cut-off.

Conclusions:
Individuals with the novel herein defined phenotype of 24hr IaoSH constitute a non-neglectable percentage of the population that cannot be identified by brachial arm ABPM, possibly carrying high cardiovascular risk as suggested by the more frequent LVH. Outcome studies are needed to verify these results.