Current Hypertension
Reviews
ISSN: 1573-4021
Current Hypertension Reviews
Volume 4, Number 1, February 2008
Contents
Interactions Between Hypertension and Hypercholesterolemia:
From Epidemiology to Therapeutic Implications Pp.
1-7
Claudio Borghi, Guido Grassi and Stefano Taddei
[Abstract]
Genetic Basis of Renal Mass in Rat Models
Pp. 8-16
Alan Y. Deng
[Abstract]
Pulmonary Hypertension and Lung Transplantation
Pp. 17-29
Paolo Feltracco, Eugenio Serra, Stefania Barbieri, Giacinto
Lunardi, Moira Milevoj and Carlo Ori
[Abstract]
Fast Food Versus Slow Food and Hypertension Control
Pp. 30-35
D. Pacioni, G. Vitolo, L. Staiano, E. Riccio, G. Gaetano
and L.A. Ferrara
[Abstract]
The Accuracy of Self-Reported Hypertension: A
Systematic Review and Meta-Analysis Pp. 36-62
Sarah Connor Gorber, Mark Tremblay, Norm Campbell and
Jill Hardt
[Abstract]
Effects of Static Magnetic Fields on Blood Pressure
in Animals and Humans Pp. 63-72
Hideyuki Okano
[Abstract]
Post Dural Puncture Headache and Hypertension
Pp. 73-77
Nalini Vadivelu, Christian Whitney, Gopal Kodumudi and
Mari Gudin
[Abstract]
Abstracts
[Back to top]
Interactions Between Hypertension and Hypercholesterolemia:
From Epidemiology to Therapeutic Implications
Claudio Borghi, Guido Grassi and Stefano Taddei
Hypertension and hyperlipidemia frequently co-exist in
the same patients and are responsible for an increase in the
extent of cardiovascular risk. The treatment of both risk
factors clearly improves the individual risk profile. The
possible mechanisms of interaction seem to be related with
RAS activation, resulting in endothelial dysfunction and increased
oxidative stress. The underlying mechanisms of the interaction
between these two risk factors may reveal the development
of new treatment strategies to control both factors at the
same time. Available data on therapeutic approach of cardiovascular
disease risk suggests the use of RAS blocking agents, calcium
channel blockers and statins can be particularly appropriated
for the prevention of cardiovascular risk in patients with
hypertension. These classes of drugs improve endothelial function
and protect the vessels wall from atherogenesis. The results
of trials carried out with the combination of a statins (atorvastatin)
and a calcium channel blocker (amlodipine) clearly support
the important of such combination for the achievement of specific
targets of treatment in patients with multiple risk factors.
Although many preclinical and clinical studies offer positive
effects of the combined use of statins and ARBs for patients
with increased risk of cardiovascular events, there is yet
need for direct evidences of their efficacy in preventing
events in high risk patients.
[Back to top]
Genetic Basis of Renal Mass in Rat Models
Alan Y. Deng
Renal hypertrophy is an important contributor to end-stage
renal disease, but little is known about its underlying physiological
mechanisms, primarily because of complex etiologies, intricate
gene-gene and gene-environment interactions. Kidney mass (Km)
can be viewed as a proximal predictor of renal hypertrophy
and, consequently, identifying the physiological mechanisms
determining Km will probably facilitate our understanding
of the factors causing renal hyper-trophy. Genetic approaches
are powerful in detecting etiological steps involved in pathways
and cascades leading to Km control. Recent genetic analyses
employing inbred rat models have defined 2 broad categories
of genes known as quantitative trait loci (QTLs) responsible
for Km. The first class controls Km independently of cardiovascular
and hemodynamic phenotypes, suggesting that their underlying
physiological mechanisms can be renal-specific and dissociated
from those regulating cardiovascular traits. The second class
of QTLs modulates Km as well as cardiovascular phenotypes,
implying that these renal and cardiovascular traits may share
physiological mechanisms. It is expected that some of the
mechanisms discovered in animal models may be translated into
humans. The strategies of gene discovery for KmQTLs consist
of identifying gene candidates (e.g. gene profiling and targeted
mutation screening) and in vivo functional validation
(e.g. fine congenic resolution, transgenesis and gene targeting).
[Back to top]
Pulmonary Hypertension and Lung Transplantation
Paolo Feltracco, Eugenio Serra, Stefania Barbieri, Giacinto
Lunardi, Moira Milevoj and Carlo Ori
Pulmonary hypertension (PH) is a disorder with poor prognosis
sustained by progressive elevation of pulmonary vascular resistance
to blood flow. It is a serious condition for which treatments
exist but there is no cure. The main determinants are vasoconstriction,
pulmonary vascular remodelling, and in situ thrombosis
associated with exuberant cellular proliferation and
precapillary arterial bed obstruction. When unrecognized or
untreated, PH has an unpredictable but worsening course that
leads to cardiorespiratory decompensation.
In the past ten years there have been significant improvements
in both diagnostic and therapeutic strategies that have led
to substantial changes in prognosis. However the number of
subjects who over time become unresponsive to maximal medical
treatment is still considerable so that surgical interventions
are needed as last chance for survival. Lung transplantation
(LTx) is a viable therapy for severe symptomatic PH. Even
though survival after LTx has improved consistently, the recipients
with an underlying diagnosis of PH seem to be affected by
a greater 1-year mortality following LTx compared to recipients
with other diagnoses.
This article discusses the disease mechanisms and the pathophysiological
processes involved in the development of PH. It provides some
information on current and newer pharmacologic options, and
it also considers the physiologic aspects of lung transplantation.
[Back to top]
Fast Food Versus Slow Food and Hypertension Control
D. Pacioni, G. Vitolo, L. Staiano, E. Riccio, G. Gaetano
and L.A. Ferrara
Epidemiological studies have demonstrated that changes
in the lifestyle, in particular in the dietary habits, strongly
contribute to the development of hypertension and other cardiovascular
diseases. In the past two decades, in many western countries,
type and mode of consumption of daily food intake changed
accordingly to the changes in the rhythms of life. The solution
of consuming fast food is obviously time-saving but it associated
to the strong enhancement in the intake of calories, saturated
fats, soluble carbohydrates and salt. All these nutrients
are able to deteriorate the metabolic profile of the cardiovascular
risk. Moreover the habitual consumption of fast food has been
frequently indicated as one of the main causes of the lack
of dialogue in the family, which is no-more gathered around
the table to consume dinner.
The alternative choice to the fast food is the slow food that
promotes the recovery of the taste and quality of food, based
on the traditions of the Mediterranean diet. In particular,
this type of diet is rich in indigestible carbohydrates, unsaturated
lipids, vegetable, proteins and potassium, which is the first
physiological sodium antagonist. This diet has been proved
to beneficially affect blood pressure regulation, to reduce
serum lipids, blood glucose and cardiovascular risk profile.
Moreover particular attempt to the size of portions is also
able to prevent increase in body weight, which is one of the
most important undesirable effects of the Mediterranean diet.
Fans of the slow food suggest to consume the meal sitting
around a carefully prepared table, enjoying talks and food,
in order to antagonize the stress of the daily life in the
21st century.
Aim of this paper is to show two different menu, one typical
of the fast food and the second typical of the slow food philosophy,
and discuss about their composition along with the effects
of their macronutrients on blood pressure, body weight, serum
lipids and blood glucose.
[Back to top]
The Accuracy of Self-Reported Hypertension: A Systematic Review
and Meta-Analysis
Sarah Connor Gorber, Mark Tremblay, Norm Campbell and
Jill Hardt
Hypertension is a leading cause of morbidity and mortality
with surveillance often based on self-reported data. A systematic
review and meta-analysis was completed to determine what empirical
evidence exists regarding the agreement between measured and
self-reported estimates of hypertension. Four electronic databases
were searched to identify observational and experimental studies
on adult populations. Searching identified 144 studies that
examined the relationship between self-reported and directly-measured
hypertension. Studies demonstrate that the prevalence of hypertension
based on self-report is underestimated and that awareness
levels are low and highly variable, ranging from 0 to 97%.
Meta-analysis generated overall awareness estimates of 58%
at the 140/90 mmHg cut-off and 62% at the 160/95 mmHg cut-off.
Awareness levels were consistently higher for females. In
many of the reviewed studies, standard guidelines for blood
pressure measurement were not being followed or reporting
of guideline compliance was poor. Lack of awareness is an
important public health issue, yet this review demonstrates
that the current practice of surveillance based on awareness
alone is insufficient. These data indicate the importance
of directly measuring blood pressure according to standardized
protocols wherever possible, and increasing population awareness
both to increase the validity of self-report and to ensure
early diagnosis and treatment.
[Back to top]
Effects of Static Magnetic Fields on Blood Pressure in Animals
and Humans
Hideyuki Okano
It is presumed that life on Earth has evolved in the
presence of natural and ubiquitous magnetic fields. It is
not surprising that biological systems can respond to a wide
range of static magnetic fields (SMF). It is suggested that
some physiological responses seem to be mediated through the
nervous system. For weak intensity SMF, the effects of geomagnetic
activity on the arterial baroreflex (reflex initiated by receptors
in the aortic arch that alter peripheral vasomotion) in conscious
animals were investigated by measuring blood pressure and
microcirculation. Baroreflex sensitivity (BRS) was assessed
as an indicator of cardiac autonomic regulation on the basis
of the heart rate/mean arterial blood pressure relationship
during a vasodilator (sodium nitroprusside) or a vasoconstrictor
(phenylephrine) treatment. This study suggests that the geomagnetic
field directly modifies microcirculatory responses related
to BRS. These findings may have serious implications for individuals
with ischemic diseases during periods of intense geomagnetic
activity or geomagnetic storms. Concerning the moderate intensity
SMF effects, pharmacological procedures and experimental animals
have been used to assess the sympathetic responsiveness to
SMF. We have reported that continuous exposure to moderate
intensity SMF for several weeks can depress or suppress the
action of sympathetic agonists (norepinephrine, phenylephrine,
and dobutamine) and a sympathetic antagonist (reserpine) on
hemodynamics and/or blood pressure by modulating sympathetic
nerve activity or BRS in animals. In contrast, in humans there
is little evidence to suggest that the SMF exposure of up
to 8 tesla can alter blood pressure. Thus, this review describes
the SMF effects (and non-effects) on the blood pressure in
animals and humans.
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Post Dural Puncture Headache and Hypertension
Nalini Vadivelu, Christian Whitney, Gopal Kodumudi and
Maria Gudin
Post dural puncture headache and hypertension (PDPH)
is a low pressure headache closely related to Cerebrospinal
fluid (CSF) hygrodynamics. PDPH occurs because of a CSF leak
that occurs as a consequence of a dural puncture. The leakage
of CSF produces traction on the brain and the meninges and
causes compensatory cerebral vasodilatation resulting in a
headache. Cerebrovascular autoregulation is a gradual process
which minimizes intracranial pressure changes in the presence
of systemic blood changes. Cerebral autoregulation prevents
the cerebral blood vessels from dilating in moderate hypertension.
There is a loss of autoregulation in end stage intracranial
hypertension where there are passive changes in cerebral blood
flow and cerebral blood volume, when there are changes in
the systolic pressure. Hypertensive encephalopathy is associated
with the breakdown of the blood brain barrier and is a complication
of chronic severe hyper-tension Since the cerebral venous
system has no valves fluctuations in the systemic venous pressure
will directly affect CSF pressure. There is increased drainage
of CSF into the venous system secondary to increased CSF pressure
in severe systemic hypertension.. It appears that CSF volume
is decreased in the presence of systemic hypertension however
it is still unclear if the CSF pressure in systemic hypertension
is decreased as well. Clinical data on post dural puncture
headaches in the presence of hypertension in humans is rare.
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