Around 75% of the heart attacks and about
85% of the strokes are caused by a clogging of an artery (caused by atherosclerosis) with plaque that has leaked from the
artery wall. There are three effective ways to slow the development of atherosclerosis: diet, exercise, and drugs (nicotinic acids, statins, fibrates, and resins). Considering that around 40%
of Americans do not have medical insurance and that niacin is inexpensive, effective, safer than prescription drugs, obtained
without a prescription; it ought to be taken in medicinal amounts (2-3 grams per day) by those in the higher risk group for
coronary disease—those with elevated levels of LDL and cholesterol. SOURCES:
2002 |
|
Statins These drugs produce the greatest reduction in blood borne
lipoproteins the most marked reduction of CHD. This association has been overstated
for they also reduce thrombi—just like aspirin. Their aspirin like effect
in reducing MI (myocardia infraction) ought to be included in the evaluation of statins’ effectiveness. Statins are competitive inhibitors of 3-hydroxy-3methylgultaryl
coenzyme A (HMG-CoA) reductase, which catalyzes an early, rate limiting step in cholesterol biosynthesis. They can also reduce triglyceride levels caused by elevated VLDL.
Rates of side effects approach that of the placebo group.
Statin affect cholesterol levels by inhibiting hepatic cholesterol
synthesis, which results in increased expression of the LDL receptor gene. Triglyceride levels >250 mg/dl are reduced substantially by statins, and the percent reduction is similar to the reduction in LDL-C. For the highest dose (simvastatin
and atorvastitin, 80 mg/day) reduction of 35-45% for both LDL-C and triglycerides. A
similar reduction in triglycerides can be achieved with fibrates or niacin. Statins
also raise HDL levels, though studies have not shown if the modest rise is clinically significant. A multitude of potentially cardio-protective effects are being ascribed to these drugs [by big PHARMA];
however, the mechanisms of action for non-lipid lowering roles has not been established and thus it is not known of these
putative effects are biologically or clinically relevant. The vulnerability of plaques to rupture and thrombosis is
of greater clinical relevance than the degree of stenosis they cause. Statins
may affect plaque stability in a variety of ways. They reportedly inhibit monocyte
infiltration into the artery wall in a rabbit model, and inhibit macrophage secretion of matrix metalloproteinases in vitro. The metalloproteinases degrade extracellular matrix components
and thus weaken the birous cap of atherosclerotic plaques. Other effects proffered
by big PHARMA include inhibiting of smooth muscle cells in artery walls, and enhancing apoptotic cell death. Statins decrease C-reactive protein (CRP), an independent marker for inflammation and high CHD risk. However, CRP might be a marker for the metabolic syndrome (obese, insulin resistant)—and
not for atherosclerosis. CRP reduction has been shown to modestly reduce CHD,
this might be because of better managing of those with metabolic syndrome. Statins have been shown to reduce the oxidation of LDL in
both in vitro and ex vivo studies. Statins reduce [like aspirin] platelet aggregation
and reduce the deposition of platelet thrombi in the porcine aorta model. [The
separating of the thrombi effect from that of LDL effect on reduction of CHD would significantly impact statins prudent usage—jk]. After an oral dose, plasma concentrations of statins peak
in 1 to 4 hours. The half-lives of the parent compounds are 1 to 4 hours, except
atorvastatin and rosuvastatin which have half-lives of about 20 hours, which probably account for these drugs greater effect
upon LDL. More than 70% of statins metabolites are excreted by the liver with
subsequent elimination in feces. Serious adverse effects are truly rare when administered
alone. There are serious drug interactions.
The myopathy (muscle pain) syndrome is characterized by intense myalgia similar to flu-related myalgia. Since myopathy
rarely occurs in the absence of combination therapy routine CK monitoring is not recommended unless the statins are used with
one of the predisposing drugs. Bile-Acid Sequestrants The two established bile-acid sequestrants resins (cholestyramine
and colestipol) are among the oldest of the hypolipidemic drugs, and they are probably the safest, since they are not absorbed
from the intestine. Because statins are so effective at lowering LDL, resins
are used as a second agent if statin therapy does not lower LDL sufficiently. Maximal
doses (24-30 g) can reduce LDL by up to 25%, but are associated with unacceptable gastrointestinal side effects (bloating
and constipation) that limit compliance. In a 1984 study cholestyramine therapy
reduced total cholesterol by 13% and LDL by 20% (diet 5% and 8%) and CHD events by 19%.
The bile-acid Sequestrants are highly positively charged
and bind negatively charged bile acids. Because of their large size the resins
are not absorbed, and the bound bile acids are excreted in the stool. Since over
95% of bile acids are normally reabsorbed, interruption of this process depletes the pool of bile acids, and hepatic bile-acid
synthesis increases. As a result, hepatic cholesterol content declines, stimulating
the production of LDL receptors, an effect similar to that of statins. The increase
in hepatic LDL receptors increases LDL clearance and lowers LDL-C levels, but this effect is partially offset by enhanced
cholesterol synthesis caused by up-regulation of HMG-COA reductase. Inhibition
of reductase activity by statin substantially increases the effectiveness of the resins.
Fibric Acid Derivatives Fibrate are a class of amphipathic carboxylic acids used
mainly for hypercholesterolemia. In 1967 the ester form (clofribrate) was approved
by the FDA. Fibratres most effectively reduce triglycerides and raise HDL levels.
Its use declined dramatically after the World Health Organization reported in
1978 that despite a 9% reduction in cholesterol levels, clofibrate treatment did not reduce fatal cardiovascular events. Subsequent drug company sponsored studies
have shown a modest reduction in mortality. Fibrates decrease plasma triglyceride by increasing the
activity of lipoprotein lipase, which hydrolyzes triglycerides from VLDL particles.
Fibrates also decrease hepatic cholesterol synthesis and increase cholesterol excretion in bile. Commonly prescribed are bezafibrate, cirofibrate, clofibrate,
gemfibrozil, and fenofibrate. Despite extensive studies in humans, the mechanisms by which fibrates lower lipoprotein levels
and raise HDL levels remains unclear. Recent
studies have shown that fibrates activate PPAR (peroxisome proliferators activated receptors) especially PPARα., and
there effect seems to be through enhanced clearance of VLDL. Fibrates are structurally
and pharmacologically related to the thiazolidinediones, a novel class of anti-diabetic drugs that also act on PPARs (more
specifically PPARg. Most of the fibric acid agents
have antithrombotic effects including the inhibition of coagulation and enhancement of fibrinolysis. Thus the salutary effects could be mostly from altering cardivovascular outcomes by mechanisms unrelated
to any hypolipidemic activity; this lead to the conclusion for this reviewer to recommend
aspirin instead of fibrates except for severe hypertriglyceridemia and chylomicronemia syndrome. Goodman and Gilman recommends fibrates for subjects with triglycerides
>1000 mg/dl who are at risk for pancreatitis and have a role in subjects with high triglycerides and low HDL levels
associated with pancreatitis or type 2 diabetes mellitus. Many experts first
treat such patients with a statin, and then add a fibrate. However, statin-fibrate
combination theapy has not been evaluated in outcome studies.
In a 5-year study of hyperlidemic men, gemfibrozil reduced total cholesterol by 19% and LDL by 11%, raised HDL by 11%,
and decreased triglycerides by 35%. Overall there was a 34% decrease in the sum
of fatal plus nonfatal cardiovascular events, but without effecting total morality. Again Goodman and Gilman suggest that this benefit was from the same mechanism as
for aspirin and not its effect on lipids. Side effects occur in 5-10% of patients, but most often
are not sufficient to cause discontinuation of the drug. The usual dose is 2
g per day in divided doses for clofibrate, 600-mg dose for gemifbrozil taken twice a day, fenofibrate 145 mg daily. Ezetimbe and the Inhibition of Dietary Cholesterol Uptake Ezetimibe is the first compound approved for lowering total
and LDL-C levels that inhibits cholesterol absorptioin by enterocytes in the small intestine.
It lowers LDL-C levels by about 18% and is used primarily as adjunctive therapy with statins. Outcome studies have recently started. Dual therapy with these
two classes of drugs prevents enhanced cholesterol synthesis induced by ezetimibe and the increase in cholesterol absorption
induced by statins; there is thus a 15-20% reduction in LDL-C. Increasing statin
dosages from the usual starting dose of 20 mg to 80 mg normally yields only an additional 12% reduction in LDL-C, whereas
adding ezetimibe, 10 mg daily to 20 mg of a statin will reduce LDL-C by an additional 18-20%.
Ezetimibe is highly water insoluble, precluding studies
of bioavailability. After ingestion, it is glucuronidated in the intestinal epithelium,
absorbed, and enters an enteroheptic recirculation. Pharmacokinetic studies indicate
that about 70% is excreted in the feces and aboutg 10% in the urine. Bile acid
Sequestrants inhibit absorption of ezetimibe. Other risk factors high levels of lipoprotein
A, homocysteine, Apoprotein B
There
has been an extraordinary amount of news attention focused on recent studies concerning statins and heart disease, presented
at the American College of Cardiology meetings in March and, in one case, published in the April 8, 2004 New England Journal
of Medicine. Without
disparaging the importance of the studies themselves, we believe that spin-doctors and a scientifically uncritical news media
have interpreted and stretched the findings in ways that go far beyond the actual data from the studies. A few examples will
illustrate this: Misinterpretation #1 Statins will prevent heart disease even in people who have not yet had a heart attack, stroke, angina or other kinds
of cardiovascular disease if they have elevated cholesterol levels. {WEAK EVIDENCE FOR STATINS FOR THOSE WITH ONLY HIGH CHLOSTERAL}:
Although there are some earlier studies involving people without previous evidence of cardiovascular disease (angina,
heart attacks, bypass surgery, angioplasty or strokes), the evidence for treatment of these people, especially with cholesterol-lowering
drugs, is weaker and is known as primary prevention. This is especially so
for those people who do not have more than one of the risk factors listed below: These
risk factors include hypertension, diabetes, smoking, obesity, or a close family history of premature heart attacks or strokes.
Other predisposing risk factors include a sedentary life style and a high-fat diet. It is likely that millions of people being
given cholesterol-lowering drugs such as statins for primary prevention do not have more than one of these risk factors and
are only being treated because of their total cholesterol or LDL cholesterol levels. Thus,
it is extremely important to look at the global risk of cardiovascular disease rather than focusing on just the blood pressure
or just the cholesterol level. For primary prevention, it is usually most prudent to attempt to improve your cardiovascular
risk through sensible programs of diet and exercise. A case
example of primary prevention involving someone who will, unfortunately, more times than not be recommended to start statins
follows: Ben is
a 55-year-old man with a total cholesterol of 240 and an HDL of 50. However, his blood pressure is a normal 120/90 and he
is neither a diabetic nor does he smoke. Ben turns out to have a 5-year risk of having a cardiovascular event (heart attack,
stroke, etc) of only 5.1%, about one-half of the 5-year risk of over 10% that might merit drug treatment. It would be a good
idea for Ben — or most people, for that matter—-to adopt the non-drug approaches to lowering his cholesterol discussed
above, but since his global risk is as low as it is, drug treatment is not indicated even if his total cholesterol and
HDL cholesterol stay the same. In summary,
these new studies did not even examine the role of statins in primary prevention. There are many people who have had heart
attacks and strokes with elevated cholesterol levels who are not being aggressively enough encouraged and helped to lower
their subsequent risk with diet, exercise or statins, the very kinds of secondary prevention the studies did address. Misinterpretation #2 The study showed that atorvastatin (LIPITOR) prevents heart attacks. It is
correct that the study showed that those taking atorvastatin were significantly (16%) less likely than those taking pravastatin
to have any of the above events — and this is an important finding. However, there was not a significant reduction in heart attacks alone, death alone, or in the combination
of death and heart attacks. The most significant reduction in the Lipitor group was in the subsequent occurrence of unstable
angina requiring hospitalization. Misinterpretation #3 The studies prove that atorvastatin (LIPITOR) is superior to pravastatin (PRAVACHOL). As mentioned
above, the purpose of the study was to see how intensive statin therapy (80 milligrams daily of atorvastatin) compared to
standard therapy (40 milligrams of pravastatin) in people who had already had a cardiovascular event. There is reason to believe
that the most important variable may be the intensity of the treatment rather than characteristics of the individual drugs. Ideally,
the study should have explored both the different drugs and different doses — standard or intense — of each. Cholesterol-lowering Drugs For People 70 or Older Aside
from these recent papers, there is still some misinformation about the evidence for treating — in the form of primary
prevention — elevated cholesterol levels in people over 70 years of age. It is
clear that the relationship between moderately elevated cholesterol levels and increased risk of heart disease is not as clear
as people get older. As geriatricians Fran Kaiser and John Morely have written: “Given the uncertainty of the effects
of cholesterol manipulation in older individuals, what should be the approach of the prudent geriatrician to hypercholesterolemia
[elevated blood cholesterol levels]? In persons over 70 years of age, lifelong dietary habits are often difficult to change
and overzealous dietary manipulation may lead to failure to eat and subsequent malnutrition. Thus in this group minor dietary
manipulations such as the addition of some oatmeal [or other sources of oat bran or soluble fiber] and beans and modest increases
in the amount of fish eaten, may represent a rational approach. Recommending a modest increase in exercise would also seem
appropriate. Beyond this, it would seem best to remember that the geriatrician’s dictum is to use no drug for which
there is not a clear indication.” The
use of cholesterol-lowering drugs in people 70 or older should be limited to patients with very high cholesterol levels (greater
than 300 milligrams) and those who manifest cardiovascular disease (previous history of heart attack or angina, stroke). More
recent reviews of this topic have reached similar conclusions: In one review, it was concluded that “unanswered questions
include cholesterol treatment for primary prevention in the elderly, gender effect, and benefit of treatment in persons older
than 70.” There are even questions as to whether elderly people who are hypertensive should have their cholesterol lowered
by drugs. One review concluded that “Further trials are required before routinely suggesting that it is advantageous
to lower cholesterol in an elderly hypertensive who does not have pre-existing evidence of coronary heart disease.” What You Can Do If your
doctor recommends a cholesterol-lowering drug, especially for primary prevention, ask on what basis this is being done. This
is especially true if you either are over age 70 or have no more than one risk factor. Those who have a financial interest in the outcome manipulate the results, Major study finds that all 37 journal articles positive effects over stated; the average was 32%. Statins cause erectile
dysfunction, cognitive imparement, and cancer. Lipitor (2011) lifetime sales $131
billion, tops all drugs. Plavix at
$60 billion is second. STATINS CANCER Link 52% short term LA Times, Health section, Vytorin, the
combination drug (simvastatin (better known by its commercial name Zocor) and ezetimibe--known as Zetia) prescribed to lower
cholesterol, sustained another blow today, when the author of a major clinical trial announced that the medication had failed
to drive down hospitalization and death due to heart failure in patients with narrowing of the aortic valve. In the process,
researchers in Today's findings
suggested something more ominous: the incidence of cancer -- and of dying of cancer -- was significantly higher in the patients
taking Vytorin. Altogether, 67 patients on placebo developed cancer during the trial.
Among subjects on Vytorin, 102 developed cancers of various kinds.* This
is the second adverse press—the first being in March 08, when the ENHANCE trial found that Vytorin fared no better than
a placebo at reducing plaque buildup on the walls of patients' arteries.* * Comments
by jk Simvastatin (Zocor) is off patent. Thus in a scramble for profits a combination drug (on patent) was introduced. Direct to consumer market cost $155 in 07—mainly TV ads. *
The pressing issue is that since the development of Statins, the very
first animal studies in the 60s it has been known that Statins increase the incidents of cancer. However, nearly all studies done thereafter have not included cancer.
*
Several studies have failed to find a reduction in the build of plaque, even thought the statins including Zocor, reduce
EXTENDED RELEASE NIACIN IS A SAFER, AND A MORE EFFECTIVE WAY TO LOWER
MI RISK! |