Hypertension
Origin And StatisticsAbout 50 million people in the U.S. suffer from hypertension.
It is more common among women than men, but is even more common among black women,
particularly after the menopause and beyond age 65. There is a public health crisis
going on, as Ref. 2 describes that 75 % of the 50 million Americans who have hypertension
are at risk for getting cardiovascular complications such as heart attacks or
strokes. There are deficiencies in diagnosing and treating hypertension
as it is painless and people who should have their blood pressure measured regularly
do not get this done.
The
authors describe that many physicians are not aware of the 1997 guidelines from
the Joint Committee (Ref.1) and as a result they use old outdated much higher
cutoff points before treatment is instituted. There are also problems with under-
and overtreatment according to Ref.2. Hyman et al.(Ref. 3) reiterates that many
physicians have much higher treatment thresholds than the Joint Committee's 140/90
target, which leads to underdiagnosing hypertension and unwillingly putting patients
at risk by not treating them. Also, these authors observed that once treatment
has been started, patients are not treated adequately to normalize their blood
pressures. Most people (85 to 90%) with hypertension have "primary
hypertension", which is also known under the name "essential hypertension".
This term is used to indicate that we do not know the cause of why these patients
have high blood pressure. The other group(10 to 15%) is said to have "secondary
hypertension". The causes for the high blood pressure in this group
is disease of the kidneys (where the powerful renin-angiotensin mechanism is activated),
pheochromocytoma, hyperthyroidism, hypothyroidism, primary aldosteronism, Cushing's
syndrome, renovascular disease and coarctation of the aorta. Most of these conditions
involve some form of powerful hormone changes or some structural changes in the
kidneys. Several chronic kidney diseases are associated with hypertension such
as glomerulonephritis, pyelonephritis, obstruction of the ureter from a kidney
stone, congenital polycystic kidney disease and connective tissue disease affecting
the kidneys. Despite what I said above about primary (essential) hypertension
quite a lot is known about this entity. Many authors now think that there is not
one cause, but a combination of various factors that interact,
all leading to hypertension. Such known factors are: stress leading to overstimulation
of the sympathetic nervous system, sodium retention from overindulgence of salt
and hereditary factors poorly understood so far. Absence of such substances as
prostaglandins and others, which are found in kidney tissue and have a relaxing
effect on arterial walls, can also lead to hypertension.
This
likely may be the major mechanism for hypertension in the case of chronic kidney
diseases mentioned under secondary hypertension, where the tissue of the kidneys
gets damaged. The lack of these arterial wall relaxing substances allows the other
powerful artery constricting substances, renin and angiotensin as well as epinephrine
and norepinephrine, to get the upper hand. Newest development in
the quest to find the cause of high blood pressure: Dr. Nathan Bryan
(Ref. 10) presented evidence from the literature about the basic research into
the causes of high blood pressure, heart attacks and strokes. He also talked about
this at the 19th Annual World Congress on Anti-Aging and Aesthetic Medicine in
Las Vegas (December 8-10, 2011). The common denominator in these illnesses is
a lack of nitric oxide (=NO) production in the arterial walls of these patients.
NO is a gas and this is what diffuses through the lining of the arteries and relaxes
the surrounding smooth muscle cells, thus widening the arteries and lowering the
blood pressure. This in turn will prevent hardening of the arteries, heart attacks
and strokes. Nitric oxide is also formed from green leave vegetables, such as
spinach, kale and lettuce, which contain natural nitrates and nitrites. The bacteria
in the mouth and stomach metabolize the nitrates into nitrites and nitric oxide,
which is absorbed in the small bowel. Too much fat, too much starch and sugar
will interfere with the formation of NO. |
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