Archive for April, 2010
What About the Kids…
In my last blog, I wrote about the issue of being overweight and the rise of diabetes. I have also blogged about exercise and not watching television, unless you are exercising while you are viewing. Now let’s talk about the kids.
The CDC recently published data from the NHANES survey of 1999 to 2006. As you will recall, the National Health and Nutrition Examination had data for 9187 youths, ages 12 to 19 years-old. Of these respondents, 3733 had fasting lipid profiles reported.
20% of these youths had at least one constituent of the lipid panel abnormal. These constituents are triglycerides, LDL cholesterol and HDL cholesterol. The values used were LDL cholesterol >130 mg/dl, reduced HDL <35 mg/dl or elevated triglycerides levels > 150 mg/dl.
Those youths, who were overweight, had significantly more abnormal values than those who had BMI (body mass indexes) that were normal. In addition, boys were more likely than girls to have low HDL and the older these youths became, the more likely it was that their HDL was low and their triglyceride values high.
Screening lipids is now recommended for young patients by the American Academy of Pediatrics. Just based on elevated BMI i.e., they are overweight. It is thought that more that 30% of youths would need to be screened and many would be found to have abnormalities. It is also recommended for family history of high cholesterol or premature cardiovascular disease or an unknown history but one risk factor which includes obesity.
It is recommended that these children receive statin drugs but this is still controversial. I have many patients in my practice who have had early coronary disease and many of these patients have chosen to treat their children. This illness starts at an early age with the first pathologic indications appearing in patients in their late teen or early twenties. To combat this, we will have to treat the children until we have a better understanding of the process and until we have a better agent with which to control it. Until then, diet, exercise, and yes in some cases statins are called for. If we do not control this, it will add immeasurably to our ongoing health care crisis. We must start now.
The Opportunity We Lost
Healthy People 2010 was launched in 2000. The aim of this project was to reduce the number of cardiovascular deaths by 20%. This is certainly a worthy project. The results were published in the Bulletin of the World Health Organization in February.
I’m sure you can guess but we didn’t make it. 400,000 deaths in the U.S. from cardiovascular disease are projected to occur this year. I want to put this into perspective. 416,000 servicemen and women died during World War II. Each year, we lose that many people to heart disease. You would think there would be uproar. The only sound I hear is snacking.
What exactly seems to be the problem? We have had a reduction in improved total cholesterol and in lower blood pressure in men. We have also increased physical activity and decreased smoking. However, this is almost totally offset by an increase in obesity and diabetes.
We must rethink the balance of government and personal responsibility. The government does not make us eat more or make us fat. The government can limit the salt in food and demand that soft drinks be removed from schools. We can develop all sorts of medications, but it seems to come down to what will you do for yourself and most of it seems to revolve around how much you eat. Most diabetes is related to simply being overweight. This is a personal responsibly and until we grasp this future progress may not be made.
The most recent National Health and Nutrition Examination Survey found that most Americans are overweight and one-third are obese. Obesity has overtaken smoking as a major health burden in the United States. This is very apparent if you travel anywhere outside the United States and compare average body size. Don’t go to Disney World, it is truly disheartening.
Let’s all pledge to lose 10 or 15 pounds. We went to the moon. We can understand this problem and solve it. It won’t be solved by drugs, it must be solved by education and the simple understanding that we eat too much. Put down the remote and do something.
Correcting Urban Legends in Medicine
Urban legends are situations or things that are thought to exist but don’t. Their power is such that they can lead to excessive attempts to change behavior that didn’t need to be done in the first place.
Urban legends in medicine lead to an overuse of resources and an enormous increase in the overall cost of medical care in spite of contrary evidence. I don’t claim to know how to stamp it out. Education is one way, but people and physicians are incredibly resistant to it.
One such “Urban Medical Legend” is preoperative cardiac risk evaluation. The legend holds that it is possible to identify and then rectify the condition of patients who are at risk for cardiovascular incident and death before they have an operation. This is the so called cardiac clearance for surgery. It comes in two flavors the “emergency clearance” and the classical “elective clearance.”
Although there are Guidelines published by The American College of Cardiology in conjunction with The American Heart Association, neither are closely followed by most practitioners. The guidelines suggest that patients who have no evidence of angina or congestive heart failure are at no adverse risk for any surgery. In the process of screening for “problems” patients are generally subjected to nuclear stress tests and these tests identify those lesions that are “significant.” However, significant lesions cause angina and not myocardial infarctions and many myocardial infarctions are from lesions that are not considered significant.
The most important study done on this was a study that identified these patients and then randomized them to medical therapy and “corrective” therapy, either angioplasty or coronary artery bypass surgery. This study revealed that the “corrected group” had a statistically significant worse outcome than the medically treated group because of the incidents that occurred during the correction. This included the data for the surgery that they then went for after they were cleared.
The medical therapy most often applied is the use of preoperative beta blockers. These are drugs like Toprol and atenolol which control heart rate and blood pressure. This too has been called into question in that the routine use of these drugs can have important consequences for patients.
There is no perfect answer but what we presently do is unjustified by the data. The use of selective functional testing and the selective correction and treatment is evidence based but not necessarily the current standard of practice. This arises from legal concerns, compensation from testing and procedures and possibly from surgeons.
We as physicians need to do better. This is one area that we can make a difference in the quality and cost of health care. Beware of clearance that requires testing that you would not have gotten without the pending surgery.
Can a Substance Make You Live Longer?
As I discussed in my last blog, a substance known as resveratrol has gained much notoriety in the last few years. It was originally brought to the attention of the general public during a 60 Minutes broadcast and subsequently has gone “viral” in the amount of attention that it gets, particularly on the Internet. The science and data to date show little to no effect on humans.
The story starts when this substance was found in the skin of red grapes, and in 2003 it was found to significantly extend the life span of certain yeast species. It was subsequently given to mice and found to protect them from a high fat diet and make them run longer on the treadmill. The amount of resveratrol need in humans would be roughly 4g a day and the metabolism of this drug is severely limited in the body because of rapid metabolism.
However, the action may be on a system in the body known as Sirtuin, which produces an increase in the functioning of mitochondria. which are the power plants of our cells. This substance is the substance produced in a famous mice experiment. When mice are fed 1/3 less than they nee; they live significantly longer. No one has asked them whether they are happier though.
It is also very difficult to get humans to do this, although there is some thought that it might work as well. The thesis goes that “starvation” turns on a reparative process that is evolutionary in us and has allowed us to survive as a species when food was limited. Resveratrol supposedly turns on the system without the diet. Take the pill and eat yourself silly and while your at it don’t bother with the exercise either.
By the way, red wine contains between 0.2 and 5.8mg/l. White wine has much less. You can do the math but don’t try to get your daily dose by drinking. Most of the supplements sold in stores come from processed extract of a plant known as Japanese knotweed and contain 50% resveratrol and a substance known as emodin, which can act as a laxative. I have patients that tell me that they take it.
The Sirtuin system is being studied in many ways and may yet yield important health benefits to human. In general my patients would rather talk to the guy in the aisle at Whole Foods than me about this kind of stuff, but I find it interesting that the information generates a great deal of attention instead of randomized clinical trials. Maybe one day someone will ask me to study it in humans with cardiac disease. I promise to give it a good look.
The Answer to My Prayers, Part 2
In my last blog, I wrote about the benefit of chocolate in reducing mortality from vascular disease. Now recurrent news that light to moderate drinking reduces the risk of death from cardiovascular causes as opposed to total abstinence or heavy drinking has been published.
I say recurrent because this information has been seen before and is part of what is known as the “French Paradox.” The “French Paradox” comes from the observation that although the French eat “worse” and smoke more than we do as a country, they have less death from cardiovascular disease than we do. It originally was felt that this was due to consumption of red wine and that it was further thought to be due to a substance found in red wine called resveratrol, which is found in the skins of red grapes.
When this “French Paradox” - named by a French scientist named Serge Renaud who happens to work at the University of Bordeaux - was discussed on 60 Minutes in 1991, the consumption of red wine in the Unites States went up 44%. I will come back to resveratrol in another blog because it is a fascinating issue in itself. Let’s get back to the drinking.
This study published in J Am Coll Cardiol 2010; 1328-1335 is an observational study. That is a study which collects data but is not randomized. It is not possible to randomize people to drinking and not drinking so they self select, but when the numbers are large this tends to not be that much of a problem.
Using the US National Health Interview Survey 245,207, adults over the years 1987 to 2000 were analyzed and linked to the National Death Index in 2002. They were divided into abstainers, light 3 drinks or less per week, moderate 4-7 drinks per week for women and 4-14 drinks per week for men, and heavy more than 7 for women and 14 for men. I do not know why they made the distinction between men and women.
The risk of death was reduced 24% by drinking light or moderately than if you do not drink at all. If you drink heavily the risk is reduced only 11%.
This is the strongest evidence to date and seems to be generalized to the US population. The reason is unknown but it is postulated to be a reduction in hypertension and an increase in those pesky HDL lipoproteins. It is not related to resveratrol and any alcohol provides the effect not just red wine.
Please understand that this is not a reason to start drinking and people should control the amount they drink and be “sensible,” but it does no harm to your cardiovascular system in the described way. Your liver is another story. Don’t drink and drive. Enjoy!
An Answer to My Prayers Part 1
In my constant search for useful information to share on my blog, I have come across the most important piece yet. Chocolate is good for you. As published in the Eur Heart J 2010: DOI: 10.1093, Yes this was really published. If you consume 7.5 g per day of chocolate, you lower your risk of stroke or heart attack by 39%. Sign me up!
First the basics 7.5 grams is roughly .26 ounces or slightly more than one Hershey’s kiss which is 5 g. Not that much. Why should this be? It seems that chocolate and cocoa have a pronounced effect on lowering blood pressure and this is the cause of the beneficial effect. The real key here is the compound called flavanol. The “darker” the color of the chocolate, the more flavanol it contains. Many chocolates now come with the amount of flavanol or pure cocoa labeled on it. In general, the darker and more “bitter,” the more flavanol it contains. Many people actually prefer it to “regular” chocolate. As you could probably guess, Hershey’s is not the best to be eating for the effect. The surprise is so little of the substance is needed.
It is important to again emphasize that so little is needed to achieve such a large effect. This blog is not a license to eat the whole bag. That will just get you fat and probably diabetes to boot. One square of a 100gm bar is enough. The whole 100gms has about 500 calories. It is important to also understand that the effect on stroke levels seem to be greater than heart attack.
This is not the first time that this information has been brought forth. In a study known as the Zuphten Elderly Study, 500 men in Holland were studied and found to have the same effect. There has been no randomized trial of fake vs. real chocolate because an appropriate placebo can not be found. There is simply nothing like chocolate.
So thank the Easter bunny who brought you so much chocolate. Have 3 M&M’s and knock yourself out. Here’s to your health.
The End of Zetia?
We received news that the outcome study of ezetimibe or Zetia ,which is being performed under the name IMPROVE-IT, is slated to end in 2013. Data should then be available by the fall of 2014. Zetia’s patent expires in October 2016. Zetia earned Schering-Plough 1.9 billion dollars in 2006, and they split this money with Merck.
Let me put this in prospective. Two years before a multi-billion dollar drug undergoes patent release to generic, we will finally identify that the drug has some value beyond the lowering of a number. This is truly amazing when you think about it.
As I have blogged before in December 2009, this drug was approved on the basis of just the lowering of a chemical number and not that it reduces hard clinical endpoints. That is what this study is to determine. No one really cares if your LDL cholesterol number is lower just that fewer people die. Let me again point out that the reduction number does not need to be large just statistically significant.
There unfortunately are significant differences in that number and its meaning. Several blogs ago I discussed the new indication for Crestor. In the final analysis you have to treat 1000 patients to prevent two deaths using Crestor under its new indication. The number is significant statistically but is this indication really worth it to patients or just the company?
The issue was further clouded by the “lowering of the bar.” As Dr. Califf pointed out, (Note: I know Dr. Califf and he is one of the finest researchers in cardiology today) “because this study is done on a background of simvastatin the incremental absolute reduction in LDL is expected to be modest and as a result the anticipated absolute reduction in event rates will be modest also,” Am Heart J 2010. DOI: 10.1016
As pointed out in my previous blogs, the ARBITER 6-HALTS study findings were more valuable then these findings will be.
This goes back to the science of LDL cholesterol. It is clear that patients who have peripheral vascular disease, stroke or coronary artery disease should be on maximally tolerated statin doses for the largest effect. This goes for people who have reasonable levels of LDL reduction on small doses of drug because it is felt that some of these effects are “pleiotropic” or to put it another way “magical” and is not fully measurable. These include the decrease of the “inflammation” of the LDL.
We know at least that Zetia is not causing harm because the study was not stopped by the monitoring safety board at half way in the study. Whether it does any good and whether we can afford to pay for it as a society will be left to an answer probably at the American Heart meeting in November 2014. Stay tuned…
Our Radiation Problem…
In the past thirty years, the amount of radiation we are exposed to in the United States has doubled. As reported in the NEJM 362; 10:943-945. What has changed is the amount of radiation that we receive from medical imaging. At the present time, the amount is close to 50%. 30% of that dose comes from cardiac imaging.
If you have chest pain or there is some other abnormality that occurs that leads you to see a cardiologist frequently, the first test you will receive is a nuclear stress test. This test was performed over 9 million times last year and represents one of the largest man made contributors to radiation exposure. It also represents a huge cost to health care and this January Medicare reduced reimbursement on the test by 40%. If the patient’s nuclear stress test is positive, then the next step is often cardiac catheterization.
One would think that this sequence of tests would then often show important disease. One would then be surprised. As reported in the same issue of the NEJM and widely in the lay press this is not the case.
Using the American College of Cardiology National Cardiovascular Data Registry, which we at Holy Cross Hospital participate in, 398,978 patients who had no documented coronary artery disease was abstracted from the registry from January 2004 to April 2008. The data was then collected as to their nuclear stress tests and risk factors.
The disturbing results were that a small minority 37.6% had significant disease as defined by left main stenosis of >50% or >70% stenosis of a major epicardial coronary artery. The strongest risk factors were age, male sex, use of tobacco and the presence of diabetes, dyslipidemia or hypertension. Further, those with the highest Framingham risk scores received more noninvasive testing than those who our guidelines suggest would be benefited.
30% of the patients subjected to cardiac catheterization had no angina. As I have repeatedly blogged about the only reason for invasive tests are to treat angina that is resistant to medical management.
When the data from the whole registry was analyzed the rate of coronary artery disease went up to 60%. Still that means a full 40% of the patients being subjected to cath do not need it in the sense that nothing is found. I can tell you from experience that cath is sometimes done to “finalize” an issue and to move patients to other concerns but this does not account for 40%.
We, as physicians, need to do better to limit not just this radiation exposure but the cost of these tests. Unfortunately, this is just one of the many areas that need addressing in our health care crisis. We are at least identifying these areas and I look to the future to some of the solutions. I will keep you informed as we move forward.
The Start of Coronary Angiography
The start of coronary angiography was slow and began in earnest after a mistake was made. The reason was mostly that there wasn’t much to do with the information in the early 1960’s because bypass surgery wasn’t invented.
Dr. Charles Dotter played a seminal role in much of radiology. He is responsible for the concept of angioplasty, which started in the legs and first used ever increasing dilators to open arteries and finally went on to develop balloons for the task. Dr. Dotter was a mentor to Dr. Andreas Gruentzig, who miniaturized the balloons in his kitchen and then used them in the coronary arteries years later. In 1959, Dr. Dotter began experimenting on animals to visualize their coronary arteries by occluding the aorta and injecting contrast nonselectively. It was believed that even a small amount of contrast would kill the animal or a human.
In 1959, Mason Sones, a pediatric cardiologist, while doing an aortic root injection noticed that the catheter accidently entered the right coronary artery and visualized it. The patient sustained ventricular fibrillation and he thumped him on the chest and it stopped (luckily because cardiac defibrillators didn’t exist yet). He went into the animal lab and worked out how to inject coronaries without harming them. During this time, Sven-Ivar Seldinger in 1953 developed the technique that we still use today of entering the peripheral arteries with a small needle and using a wire to gain access to the main circulation and to move the catheters’ around.
Dr. Melvin Judkins developed many of the preformed shapes that the catheters are manufactured in to help enter the coronary arteries during the 1960’s and by the late 1960’s coronary bypass surgery was beginning and patients began to receive cardiac catheterizations for the purpose of defining their coronary anatomy. This process at first used 35mm film and required large amounts of radiation. Now, we use digital imaging and all the data is stored on a computer and the data can be manipulated for analysis by computer. The amount of radiation is significantly less.
Next…the problem now.
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