Date of Award


Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Aldo Peixoto


The purpose of this study was to investigate the different hemodynamic mechanisms underlying isolated diastolic hypertension (IDH) and systolic-diastolic hypertension (SDH) in a population of young healthy adults. We analyzed de-identified data from 207 subjects with diastolic hypertension from the ENIGMA study, a long-term prospective study of 1,668 young adults from university campuses in the United Kingdom. This dataset included age, gender, height, weight, waist size, body mass index (BMI), body surface area (BSA), peripheral and central blood pressure measurements and pulse pressures (PP), augmentation pressure (AP), augmentation index (AIx), ejection duration (ED), cardiac index (CI), stroke volume (SV), peripheral vascular resistance (PVR) and pulse wave velocities. After removing subjects who were taking vasotonic medications and those with incomplete hemodynamic information, we identified 49 subjects with IDH, defined as peripheral diastolic blood pressure (PDBP) ≥90 mmHg and peripheral systolic blood pressures (PSBP)≥90 mmHg and PSBP ≥140 mmHg. We performed multiple logistic regression and stepwise linear regression to determine what demographic, hemodynamic, and lab variables were associated with an increased likelihood that a subject would have IDH or increased PDBP respectively. Subjects were then grouped into tertiles of cardiac index (CI), indexed peripheral vascular resistance (PVRI), and carotid-femoral pulse wave velocity (PWVCF). Mean values of all hemodynamic measurements were compared across tertiles to elucidate different hemodynamic mechanisms underlying IDH and SDH. Compared to individuals with IDH, we found that subjects with SDH were significantly older (p=0.0176), taller (p=0.0079), and heavier (p=0.0025). Most subjects with IDH were female (33 out of 49 or 67% were female). In contrast, most subjects with SDH were male (66/103 or 64% were male). There were statistically significant differences in peripheral and central pressures, peripheral and central PP, CI, indexed stroke volume (SVI), PVRI, and pulse wave velocities between the two groups (p