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To find out what I mean, you need only ask: Who profits when people become diabetic? That's easy:

The pharmaceutical industry--Diabetes is a booming growth industry, a source of tens of billions of dollars of revenue, poised for enormous growth as the population ages and gets fatter. It is common for a newly-diagnosed diabetic to be given new prescriptions for two or three drugs with a monthly cost of $300. Of course, the chronic nature of the disease make this far more profitable than, say, a two week course of antibiotics. Presently, 70 new drugs are under development.

Diabetes drug maker Novo Nordisk reported a 25% increase in revenues in 2007 from diabetic agents in the North American market, along with near $2 billion increase in profit for the year. Merck's recently-released DPP-4 inhibitor, Januvia, has already sold $668 million in 2007 and is growing rapidly.

The medical device and supply industry. Take a look at the Medtronic quarterly earnings report, detailing the breakdown of their record-setting quarterly revenue of $3.7 billion:

Diabetes revenue of $269 million grew 12 percent driven by sales
of consumables, the accessories required by insulin pump users, and
continuous glucose monitoring products. Revenue from international
sales grew 31 percent over the same quarter last year.


That's what I call a growth industry.

The processed food industry. The food industry is as big or bigger than the drug industry. ADM, Kraft, General Mills all have annual revenues in the $12-50 billion range. There are plenty of others.

When we're told, for instance, that Cheerios reduces cholesterol, we're not told that it skyrockets blood sugar or triggers small LDL. When we're sold whole wheat crackers, Cocoa Puffs (which the American Heart Asscociation says is heart-healthy), or granola bars, hunger is stimulated, impulse to eat more grows, blood sugar escalates, we get fat, we get diabetic. It's a simple formula.

So be aware that there is little incentive among corporate giants in the food, medical device, or drug industries to encourage behaviors that decrease the incidence of diabetes. In fact, there is enormous financial incentive to make sure that diabetes continues to grow at the startling rate it has over the last decade.

To be sure, the drug and medical device industry will also develop better tools to deal with diabetes and its complications. But the very best way to deal with diabetes is to not develop it in the first place.

What else is there?

This question comes up frequently:

Aren't there any alternatives to heart scans performed on a CT or EBT device?

Yes, there are.

First of all, heart scans are performed best on an electron-beam CT device (EBT) or a 64-slice multi-detector CT (MDCT) device. (While they are also obtainable through less-than-64 slice CT devices (e.g., 16 slices and less), I would advise against it because of the excessive radiation exposure and poor accuracy.) CT heart scans are not to be confused with now more popular CT coronary angiograms, which are performed on the same devices but require intravenous x-ray dye and many times more radiation.(See CT scans and radiation exposure and Heart scan frustration.) Heart scans currently form the basis for the Track Your Plaque program, a program of tracking plaque in the hopes of stopping or reversing the otherwise inevitable 30% per year increase.

Let's confine our discussion to people without symptoms, meaning people like you and me sitting at home, not in an emergency room having chest pain or other similar acute symptomatic presentation.

Among the other ways to uncover hidden coronary plaque:

--Heart catheterization--to yield a coronary angiogram. Yes, this does tell us whether coronary plaque is present. However, it is invasive, expensive, and crude. (I've performed 5000 over my career; they are crude, though useful, tools in acute settings like unstable symptoms or heart attack, a different situation.) Coronary angiography is also non-quantitative. While they provide a value like "40% blockage mid-way in right coronary" or "90% blockage in left anterior descending" they do not provide a trackable lengthwise index of total plaque volume. Identifying severe blockages in people with symptoms leads to stents, bypass surgery and the like, but it is not practical nor of long-term usefulness in apparently, healthy people without symptoms.

--Carotid ultrasound--Here's is where a lot of confusion comes from. Standard carotid ultrasound (U/S) performed in virtually every hospital and many clinics will yield crude qualitative results, e.g., "16-49% stenosis (blockage) in right internal carotid artery". The crude value range is because much of carotid U/S is based on flow velocities, not just direct visualization of the plaque itself ("2-D imaging). However, if carotid stenosis of any degree is identified, the likelihood of silent coronary plaque is much greater.

Limitations: The qualitative, non-quantitative nature of carotid U/S make it difficult to follow long-term in a precise way. Also, this is carotid plaque, not coronary plaque. It makes it very difficult to follow carotid plaque as an indirect means of tracking coronary plaque. The two arterial territories, carotid and coronary, do not track together: there are divergences in many people, with carotid plaque absent in some people with advanced coronary plaque, carotid plaque more susceptible to different risk factors than coronary. So carotid U/S is helpful for its own purposes, but not terribly helpful for coronary tracking.

How about carotid intimal-medial thickness (CIMT) obtained also with carotid U/S? CIMT is a useful index of bodywide atherosclerosis. CIMT is simply a measure not of plaque (and is measured in regions of the carotid artery away from plaque), but of the thickness of the lining of the carotid arteries. Everybody has a measurable CIMT, but it thickens as atherosclerosis grows. CIMT is a radiation-free test that takes several minutes.

Limitations: Hardly anybody does it outside of research protocols. I know of no hospital or clinic in my area that performs CIMT, though it is slowly being adopted in some centers. It is also difficult to rely on repeated tests, because there is substantial variation when one technologist or another performs it. CIMT is also a flawed index of coronary plaque. When CIMT is compared to heart scan scores, CT coronary angiography, or conventional coronary angiography, CIMT correlates about 60-70% with the degree of coronary atherosclerosis.

CIMT is therefore a useful test for research, but a distant 2nd choice--if you can obtain it.

--Ankle-brachial index (ABI)--ABI is a crude measure, simply a comparison of the blood pressure (obtained with a blood pressure cuff) in the legs divided by blood pressure in the arms. The ratio is called ABI. Any ABI <1.0, meaning less pressure in the legs compared to the arms, is indirectly indicative of advanced coronary disease. ABI is, in fact, a very powerful predictor of cardiovascular events. If ABI is <1.0, your future risk for heart attack is very high, even in the absence of symptoms.

Limitations: The vast majority of people with heart disease, even those having undergone stents or bypass surgery, have normal ABI's. Virtually all people with high heart scan scores have normal ABI's. In other words, ABI is a measure of very advanced atherosclerosis only.

--Stress tests--I lump all stress tests together in their various forms, e.g., stress thallium, stress Cardiolite, stress Myoview, persantine/adenosine Cardiolite, dobutamine echocardiography, etc. Stress tests are tests of coronary blood flow, not of plaque. Stress tests are useful in people with symptoms, like chest pain or breathlessness, since stress tests are provocative tests that can help determine whether reduced coronary blood flow is the cause behind a symptom, or whether hiatal hernia, esophagitis, gallstones, pleurisy, musculoskeletal causes, or some other process is behind symptoms.

Limitations: Stress test are virtually useless in people without symptoms. This is why people like Tim Russert and Bill Clinton, both without symptoms, underwent several (Russert 3, Clinton 5) nuclear stress tests---all normal. You know what happened to them. Stress tests do not reliably uncover hidden coronary plaque in people without symptoms. Stress tests are, like coronary angiograms, non-quantitative. They are normal or abnormal.


Outside of experimental settings, that's it.

You can probably see why I advocate CT heart scans for tracking plaque. I do not advocate heart scans because I sell them (I don't), because scan centers pay me to say these things (they don't, and in fact my relationship with my usual heart scan centers has become deeply contentious, though I still endorse the technology). I say that heart scans are superior because they are, in 2008, the only way to 1) identify and 2) track coronary plaque that is easy, safe, low-radiation, and reasonably priced (<$200 in Milwaukee at 5 centers).

The need for a technology that allows tracking of plaque, not just initial identification, is also an important distinction. People who've had some measure of atherosclerosis all catch on to this eventually. "Can I reverse it?" is an inevitable question once the disease is identified in some way. So a tool for tracking over time to gauge the success or failure of a program of prevention can be assessed.

Perhaps in 10 years, another technology will emerge as the preferred means to do the same, but better. If that proves true, we will convert to that technology. But today heart scans performed on CT heart scans are the only rational way to both detect, then track, coronary atherosclerotic plaque.

Let's gamble with your health

Let's play a game.

I'm going to list some lipid patterns and you tell me whether or not the person with these values has heart disease.

Patient 1

Total cholesterol 150 mg/dl
LDL cholesterol 75 mg/dl
HDL 50 mg/dl
Triglycerides 125 mg/dl


Patient 2

Total cholesterol 300 mg/dl
LDL cholesterol 200 mg/dl
HDL cholesterol 35 mg/dl
Triglycerides 325


Patient 3

Total cholesterol 300 mg/dl
LDL cholesterol 100 mg/dl
HDL cholesterol 25 mg/dl
Triglycerides 875 mg/dl



Let's say that any one of these profiles is yours. Should you be getting your affairs in order, preparing for your cardiac catastrophe? Should you demand a stress test from your doctor, hoping that it will shed some light on your dilemma? Should you go ahead and go to the all-you-can-eat rib restaurant, content that you will be attending your granddaughger's wedding in 2020 in full health?

If you can tell, you're a lot better at this than I am.

I provide consultation to other physicians and patients on complex hyperlipidemias in my area. In other words, if someone has a difficulty to manage lipid disorder, the doctor sends the patient to me.

Managing these wildly variable values is the easy part. Deciding whether or not heart disease is concealed within the patient . . . well, that's the hard part.

Let's take it a step further: Suppose all three profiles also have 50% of all LDL particles as the abnormal small particles. And they all have a lipoprotein(a) level of 50 mg/dl, an abnormally high level.

How about now: Can you tell whether any or all of these people have hidden heart disease?

What if they are 20 years old? Does that make a difference?

What if they are all females over 65 years--how about now?

If the only tool you have to divine the presence of hidden heart disease is a lipid panel, or even a lipoprotein panel, then the best you can manage is to hazard a guess based on statistical probability. You also assume that this "snapshot" represents the sorts of values someone has had for their entire lives. You cannot factor in the fact that the first person gained 60 lbs in the last three years since completing menopause. You can't factor in that patient 2 smoked two packs of cigarettes a day for 25 years, but quit 10 years ago.

It's also foolhardy to believe that every known cause of heart disease is currently identifiable and revealed by modern-day blood testing.

A heart scan is simply a means to quantify the sum-total of risk factors--causes--that have exerted an effect up until the moment of your scan. It will reveal the quantity of coronary atherosclerotic plaque present, regardless of whether you stopped smoking 20 years ago or lost 30 lbs last year.

For these reasons, nothing can replace the value of quantifying plaque: not cholesterol, not the Framingham risk calculation, not measures of small LDL or lipoprotein(a), not the presence or absence of symptoms. In 2008, the method of choice for measuring plaque remains a CT heart scan. Perhaps in 10 years it will be some other method.

As always, let me remind Heart Scan Blog viewers that I make this point NOT to sell heart scans, which I have no reason whatsoever to do. I say this because we require a tool to track this potentially fatal disease. We require a yardstick for tracking progression or regression. The only tool that suits these purposes in 2008 is a CT heart scan.