Journal of hypertension
-
Journal of hypertension · Apr 2000
High-normal serum homocysteine concentrations are associated with an increased risk of early atherosclerotic carotid artery wall lesions in healthy subjects.
Moderate hyperhomocysteinaemia is common in the general population and has been linked with systemic atherosclerotic vascular disease. We studied the relation of sonographically determined carotid intima-media wall thickness to serum homocysteine concentrations in asymptomatic, healthy subjects. ⋯ In healthy subjects, high-normal serum homocysteine concentrations are associated with an increased prevalence of carotid artery wall thickening. The significance of the contribution of homocysteine to the variation of carotid intima-media thickness, even at concentrations previously believed to be normal, suggests a role for homocysteine as an independent risk factor for early carotid artery atherosclerosis in the asymptomatic subjects.
-
Journal of hypertension · Mar 2000
Assessment of arterial and cardiopulmonary baroreflex gains from simultaneous recordings of spontaneous cardiovascular and respiratory variability.
In usual models of cardiovascular regulation, arterial pressure drives RR interval through a simple baroreflex, and the influence of respiration is dismissed. We examined the applicability of a trivariate autoregressive model to obtain separate values of the gain of the arterial and non-arterial, i.e. cardiopulmonary, components of the lumped baroreflex, employing spontaneous RR interval, systolic arterial pressure and respiration variability. ⋯ A trivariate autoregressive model, that considers explicitly the influence of respiration, can subdivide overall, lumped, arterial pressure-heart period baroreflex gain, into two separate components, alphaart and alphacp. Only the latter is reduced by active orthostatism.
-
Journal of hypertension · Feb 2000
Association analysis of beta2 adrenoceptor polymorphisms with hypertension in a Black African population.
To determine whether or not beta2 adrenoceptor polymorphism is a risk factor for the development of hypertension in a Black South African population. ⋯ These data suggest that beta2AR polymorphism is not a risk factor for hypertension per se in this defined population. The possibility that the decreased prevalence of Glu27 in black South African populations explains blunted vasodilator responses to isoprenaline requires further study.
-
Journal of hypertension · Jan 2000
Relative influence of insulin resistance versus blood pressure on vascular changes in longstanding hypertension. ICARUS, a LIFE sub study. Insulin Carotids US Scandinavia.
Insulin resistance is associated with hypertension. The relative influences of hyperinsulinaemia and high blood pressure on vascular hypertrophy and carotid distensibility is unclear in patients with longstanding hypertension. ⋯ High systolic blood pressure was related to vascular hypertrophy, whereas hyperinsulinaemia and insulin resistance were not, suggesting that longstanding high blood pressure is a far more important determinant for structural vascular changes than insulin resistance at this stage of the hypertensive disease. However, hyperinsulinaemia and insulin resistance were associated with low distensibility of the common carotid arteries in the subgroup of never treated hypertensive patients.
-
Journal of hypertension · Nov 1999
Influence of demographic, anthropometric and lifestyle characteristics on heart rate and its variability in the population.
The purpose of this investigation was to assess the effects of age, gender, posture and their interactions, and of body mass index and lifestyle factors, on heart rate, its total variance and its variability in the frequency domain in a population-based sample of healthy subjects. ⋯ Age, gender and/or some lifestyle factors significantly affect heart rate and various components of its variability in the supine position and in response to standing. The results are similar for autoregressive modelling and fast Fourier transform, but may differ according to the units in which the spectral components are expressed.