Haemodynamics, arterial stiffness and endothelial function in young prehypertensive subjects

Prehypertension (or high-normal blood pressure) is commonly defined as a blood
pressure of 130-139/85-89 mmHg and associated with an increased risk of future
hypertension and cardiovascular disease. Hypertension is associated with
functional and structural changes of conduit arteries and endothelial
dysfunction. Compared to normotensive persons hypertensive subjects have a
two-fold increase in arterial stiffness. Pulse wave velocity (PWV) and
augmentation index (AIx), both measures of arterial stiffness, are elevated in
patients with hypertension. Information about haemodynamic properties and
endothelial function in prehypertensive subjects is scarce. Compared to
normotensive subjects, arterial stiffness is augmented in prehypertensive
patients. Endothelial dysfunction has been demonstrated in hypertensive
individuals and normotensive offspring of hypertensive parents. The presence of
increased augmentation, its possible improvement after exposure to
nitroglycerin and salbutamol and its association with arterial stifness,
systemic vascular rsistance (SVR) and endothelial dysfunction in
prehypertensive persons has not been assessed.

1. to investigate early haemodynamic alterations and endothelial function in
young prehypertensive medical students;
2. to examine the possbility to improve these haemodynamic changes after
exposure to an endothelial dependent (salbutamol) and endothelium independent
stimulation
3. the correlation between augmentation of the pulse wave, arterial stiffness,
SVR and endothelial dysfunction in normotensive and prehypertensive subjects.

Cross-sectional case-control study

Prehypertension can be considered an early stage of hypertension and is already
associated with an increased CV risk. Therefore, prehypertension provides an
excellent model to study early changes implicated in the development of
hypertension and CVD. Ultimately this may lead to a more tailor made approach
in the identification and treatment of subjects at risk of developing CVD. The
burden for the participants is relatively small, two visits of 15 minutes and
one visit of 2 hours and we do not expect side effects of the two drugs used
for the stimulation test. All assessments are non-invasive, except for one
blood sample. The risks associated with study participation are therefore
negligible.