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NAVIGATION
New Research Links For many years, doctors knew that certain risk factors -- high blood pressure (hypertension), diabetes, cholesterol levels (HDL and LDL), smoking and obesity -- increased the probability of a stroke or heart attack...but they were uncertain exactly why. Now they know that inflammation is the key ingredient. In the coming years, you will hear much more about the effect that inflammation has on the risk of stroke and heart attack. You'll also hear about the new inflammatory risk factors of C-Reactive Protein and fibrinogen. But there's no need to wait! Read The Heart Attack Germ now and learn how you can lower your risk of stroke and heart attack by detecting and reducing inflammation in your arteries! |
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The latest news about cardiovascular germs and inflammation, strokes, heart attacks,
and Alzheimer's from medical
journals around the world, updated weekly, with commentary by |
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This abstract written by Italian
researchers from the University of Palermo is a nice summary of
where the current research stands on the relationship of infection
and inflammation to cardiovascular disease. Links are to articles on
this website which provide further details. Relationship of infection, inflammation, and atherosclerosis has been a subject of intensive investigation in recent years. Potential mechanisms whereby chronic infections may play a role in atherogenesis are myriad. Chlamydia pneumoniae (Cp) infection in early life may accelerate atherosclerosis, leading to cardiovascular complications. Other infections, simultaneously occurring with Cp, may result in a synergistic effect to promote atherosclerosis. Chronic Helicobacter pylori infection is known to increase the pH level of the gastric juice and to decrease ascorbic acid levels, both of which will lead to a reduced folate absorption. Low folate hampers the methionine synthase reaction. This leads to an increased concentration of homocysteine in the blood, resulting in damage of endothelial cells. Cytomegalovirus (CMV) infection is associated with accelerated atherosclerosis following cardiac transplantation; several studies have found that patients with a previous CMV infection had a high independent risk of restenosis after coronary angiography. Inflammatory markers are independent predictors of cardiovascular and cerebrovascular events. Large population-based studies ... have also suggested the relation between the levels of CRP and risk of coronary disease. Over the past decade also another marker of inflammation has been studied; fibrinogen has been identified as an independent risk factor for CAD in several large prospective studies. All these studies suggested a new, possible role of markers of infection and inflammation beyond traditional cardiovascular risk factors, in the development and progression of atherosclerosis. However, the clinical and therapeutic implications of these results remain to be evaluated. Although antibiotic treatment of infections in CAD patients had no impact on mortality in large prospective trials, promising data is coming from smaller studies and further studies are needed to investigate the possibility to submit this category of high-risk patients to therapeutical approaches of primary prevention. |
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Two important large-scale
studies have cast doubt on the ability of antibiotics to prevent
heart attacks in patients who already have advanced heart disease. A
report in the August edition of the British Medical Journal
summarizes these two studies:(6) Two recent trials have shed important light on the theory that the respiratory pathogen Chlamydia pneumoniae might cause atherosclerotic cardiovascular disease. (7) (8) The first, by Grayston et al, was a trial of azithromycin [an antibiotic] or placebo taken each week for one year by 4012 patients with stable coronary artery disease who were followed up for four years. The second, by Cannon et al, was a trial of gatifloxacin [an antibiotic] or placebo taken for 10 days each month for two years by 4162 patients who were in hospital with an acute coronary syndrome. In neither trial did the antibiotic therapy reduce the occurrence of serious cardiovascular events, confirming the conclusion of an earlier meta-analysis of smaller studies. The first study by Grayston is of particular interest because he is a pioneering researcher into Chlamydia pneumoniae. The article then notes the links between Chlamydia pneumoniae and heart disease -- such as this and this -- and smaller scale studies which indicate the beneficial effects of antibiotic therapy for heart disease -- such as this and this. Next, the article speculates why these large scale studies showed little beneficial effect of the antibiotic therapy. Thus, although C pneumoniae organisms, whole or in part, often exist in diseased arteries, antibiotics with antichlamydial activity have no protective effect. Why might this be? Human atherosclerosis develops progressively from an early age. Taking antibiotics too late in the inflammatory process is unlikely to have an effect, a point acknowledged by the authors of the two recent trials. Detection of viable or metabolically active organisms in atherosclerotic lesions has proved to be difficult and achieved rarely. By inference, it would seem likely that such organisms are sparse in plaques so that antibiotics-however active and for whatever duration taken-may have no chance of having a discernable effect on the occurrence of cardiovascular events. The article ends by noting that antibiotic therapy should be targeted at the early stage of disease, when Chlamydia pneumoniae is circulated around the body by carrier cells. Although large advances in dealing with heart disease may come in the future from gene therapy and stem cell research, it will still be important to determine beyond question whether antibiotic therapy can or cannot reduce C pneumoniae carriage by peripheral blood mononuclear cells. A finding that carriage can be greatly reduced or abolished significantly would provide a logical basis for trials of antibiotic treatment, not in patients with myocardial infarcts, but in young people without well established atherosclerosis. Of course, vaccination of the young against C pneumoniae, although hard to contemplate at the moment, is another avenue that could be taken. Such kinds of research will undoubtedly prove difficult but without implementation, the role, if any, of C pneumoniae in cardiovascular disease will remain shrouded in mystery for many years to come. Dr. Dvonch comments: For an antibiotic to work, it must come into contact with the germ. One of the problems with cholesterol plaque is that it has no blood supply so there is no way for the antibiotic to reach the Chlamydia germs that are embedded in the plaque. As the article notes, targeting cells that carry Chlamydia in the blood stream might be the best way for antibiotics to rid the body of the Heart Attack Germ and prevent future heart disease. As I mention in the book, studies show that people with a history of taking antibiotics have reduced rates of heart disease. This may be because the antibiotic is killing the germ in places other than inside the plaque-filled artery.
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04-17-05 |
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Researchers from the University of
Wisconsin Medical School devised a study(4)
to see if young men infected with the bacteria Chlamydia
pneumoniae -- the Heart Attack Germ
-- are more likely to suffer heart attacks than similar men not
infected by the germ. A Reuters news story titled Cold Bug
Tied to Heart Attack in Younger Men reported on the study. In
part, the article noted: Christine Arcari and colleagues at the University of Wisconsin Medical School and Johns Hopkins University in Baltimore studied regular blood samples taken from soldiers aged between 30 and 50, identifying 300 of them who suffered heart attacks. They compared their blood records to 300 men who had not suffered heart attacks. Writing in the journal Clinical Infectious Diseases, the researchers said they tested each blood sample for antibodies, which provide indirect evidence of previous infection. ... Men who had high levels of ... antibodies were more likely to have had serious heart attacks, they found. And the more recent the infection, the more likely they were to have suffered a heart attack. The article concluded: The findings add to a growing body of evidence that Chlamydia pneumoniae and perhaps other infections can sometimes damage the heart and arteries, causing heart disease.(5) Dr. Dvonch comments: The importance of this study is not only that it links the Heart Attack Germ to the risk of heart attack, but that it demonstrates that active infection poses the highest risk. Active infection means that the body is currently mobilizing the immune system and producing inflammation in the arteries. I think this may account for much of the variability in studies trying to determine the link between past Chlamydia infection and heart disease. Simply having been infected with the germ in the past may not be sufficient to significantly increase your risk of heart attack. Your body has to be actively fighting the germ and creating inflammation in order for the risk to be substantial. Studies that don't take this fact into account will be flawed. |
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03-18-05 |
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Peripheral Artery Disease is a
group of diseases that cause partial or total blockage of blood flow
through the larger arteries on the periphery of the body, such as
the arm and leg arteries. More and more, medicine refers to this as
Peripheral Artery Obstructive Disease (PAOD). Atherosclerosis
(the build-up of cholesterol plaque) and the consequences of
atherosclerosis (such as blood clots) are the prime causes of PAOD. Previous studies have found that PAOD is associated with infection by the Heart Attack Germ, Chlamydia pneumoniae. It is thought that the germ creates inflammation in the artery which leads to the build-up of cholesterol plaque. Scientists believe that by killing the germ with antibiotics you may be able to reduce inflammation, which in turn reduces the risks of PAOD. To test this theory, researchers in Zurich, Switzerland treated PAOD patients infected by Chlamydia pneumoniae with the antibiotic roxithromycin and tested to see if patients showed signs of improvement over the course of time. Their conclusion? "This study provides good evidence that C. pneumoniae are involved in the progression of PAOD and that antibiotic treatment directed against C. pneumoniae is effective in inhibiting this process."(2) It seems that the Heart Attack Germ is associated with Peripheral Artery Obstructive Disease and antibiotics do reduce the risks of the disease. Or do they? Another study released just a few days later found just the opposite! This time it was researchers in The Netherlands who treated PAOD patients infected by Chlamydia pneumoniae with the antibiotic azithromycin. After a period of time, they determined survival rates and tested for signs of PAOD improvement, using the ankle-brachial pressure index (ABPI). Their conclusion? "Life table analysis showed no effect of azithromycin on survival or ABPI. CONCLUSION: A short-term course of azithromycin offers no benefits for survival or ankle pressure in PAD-patients."(3) Two similar studies -- two different results! Dr. Dvonch comments: Studies that test the effectiveness of antibiotics in treating atherosclerotic cardiovascular disease have been contradictory to say the least. As the examples above illustrate, for every study that shows the benefits of treating atherosclerosis, there's another study that argues the opposite. I'll have more to say in the coming weeks on why I think antibiotic studies have been so wildly divergent in their conclusions. |
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Two studies -- both published in the
January 6th edition of the New England Journal of Medicine --
found that lowering levels of inflammation in the body reduced the
risk of heart disease. The first study, conducted by the Cleveland Clinic, treated heart patients with varying levels of statin drugs, a type of drug used to lower cholesterol levels in the body. Statins are also known to reduce inflammation levels in the body, specifically C-reactive protein or CRP -- a type of protein associated with an increased risk of heart attack. Afterwards, patients were checked for a reduction in cholesterol, reduction of CRP levels and the progression of heart disease. As reported in American Medical News, That study concluded that patients with low CRP levels had better outcomes than those with higher levels, regardless of the cholesterol numbers. In other words, the statin's reduction of CRP inflammation was more important than the statin's reduction in cholesterol in fighting heart disease. The same article continues: The second study, conducted by researchers at the Cleveland Clinic, found that patients who reduced both cholesterol and CRP levels with statin therapy did better than those who only reduced one factor or the other. CRP was also independently associated with progression of disease. Again, statins lowered inflammation and that -- in itself -- reduced heart troubles, independent of cholesterol.(1) Dr. Dvonch comments: The important news of these studies is the effect that statin drugs have on reducing the risks of heart disease -- not because of reduced cholesterol levels, but because of reduced levels CRP inflammation, the type of inflammation most associated with strokes and heart attacks. I have previously talked about studies that show the link between statins and inflammation here and more extensively in The Heart Attack Germ, As the Cleveland Clinic study and other studies suggest, inflammation is a more important predictor of heart attack than cholesterol levels -- and statin drugs appear to be a key method of lowering inflammation in the body. |
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Site Design, Text, Graphics & Animation Copyright (c) 2003 by Russell Dvonch |
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On Sale The Heart Attack Germ is filled with cutting-edge medical information that may prevent a stroke or heart attack in your future. Topics include:
The Germs of
Cardiovascular Disease Fighting Strokes and Heart Attacks with Antibiotics Inflammatory Atherosclerosis (hardening of the arteries) The Link between Inflammation, Stroke and Alzheimer's Disease Vulnerable Plaque Stress and Triggers Vasospasm, Blood Clots and Angina hs-CRP Testing Fibrinogen Testing Mental Stress Testing Silent Strokes Inflammatory Cholesterol The Link between Gum Disease and Heart Attack and much, much more. |
