Put lipstick on a dwarf

Today, virtually all wheat products are produced from the Triticum aestivum dwarf mutant.

You might call it "multi-grain bread,""oat bread," or "flaxseed bread." You could call it "organic," "pesticide-free," "non-GMO," or "no preservatives." It might be shaped into a ciabatta, bruschetta, focaccia, or panini. It might be sourdough, unleavened, or sprouted. It could be brown, black, Pumpernickel, or white. It could be shaped into a roll, bun, bagel, pizza, loaf, pretzel, cracker, pancake, brioche, baguette, or pita. It could be matzah, challah, naan, or Communion wafers.

No matter what you call it, it's all the same. It's all from the dwarf mutant Triticum aestivum plant, the 18-inch tall product of hybridizations, backcrossings, and introgressions that emerged from genetics research during the 1960s and 70s.

According to Dr. Allan Fritz, Professor of Wheat Breeding at Kansas State University, and Dr. Gary Vocke at the USDA, over 99% of all wheat grown today is the dwarf variant of Triticum aestivum. (For you genetics types, Triticum aestivum is the hexaploid, i.e., 3 combined genomes, product of extensive hybridizations, while ancestral einkorn is a diploid, i.e., a single genome, grass. Hexaploid Triticum aestivum contains the especially hazardous "D" genome, the set of genes most commonly the recipient of genetic manipulations to modify the characteristics of flour, such as gluten content. Einkorn contains only the original "A" genome.)

No matter what you call it, add to it, how you shape it, etc., it's all the same. It's all the dwarf mutant product of tens of thousands of hybridizations.

You can put lipstick on a pig, but it's still a pig. By the way, lipstick may contain wheat.

What the Institute of Medicine SHOULD have said

The news is full of comments, along with many attention-grabbing headlines, about the announcement from the Institute of Medicine that the new Recommended Daily Allowance (RDA) for vitamin D should be 600 units per day for adults.

What surprised me was the certainty with which some of the more outspoken committee members expressed with their view that 1) the desirable serum 25-hydroxy vitamin D level was only 20 ng/ml, and 2) that most Americans already obtain a sufficient quantity of vitamin D.

Here's what I believe the Institute of Medicine SHOULD have said:

Multiple lines of evidence suggest that there is a plausible biological basis for vitamin D's effects on cancer, inflammatory responses, bone health, and metabolic responses including insulin responsiveness and blood glucose. However, the full extent and magnitude of these responses has not yet been fully characterized.

Given the substantial observations reported in several large epidemiologic studies that show an inverse correlation between 25-hydroxy vitamin D levels and mortality, there is without question an association between vitamin D and mortality from cancer, cardiovascular disease, and all cause mortality. However, it has not been established that there are cause-effect relationships, as this cannot be established by epidemiologic study.

While the adverse health effects of 25-hydroxy vitamin D levels of less than 30 ng/ml have been established, the evidence supporting achieving higher 25-hydroxy vitamin D levels remains insufficient, limited to epidemiologic observations on cancer incidence. However, should 25-hydroxy vitamin D levels of greater than 30 ng/ml be shown to be desirable for ideal health, then vitamin D deficiency has potential to be the most widespread deficiency of the modern age.

Given the potential for vitamin D's impact on multiple facets of health, as suggested by preliminary epidemiologic and basic science data, we suggest that future research efforts be focused on establishing 1) the ideal level of 25-hydroxy vitamin D levels to achieve cancer-preventing, bone health-preserving or reversing, and cardiovascular health preventive benefits, 2) the racial and genetic (vitamin D receptor, VDR) variants that may account for varying effects in different populations, 3) whether vitamin D restoration has potential to exert not just health-preserving effects, but also treatment effects, specifically as adjunct to conventional cancer and osteoporosis therapies, and 4) how such vitamin D restoration is best achieved.

Until the above crucial issues are clarified, we advise Americans that vitamin D is a necessary and important nutrient for multiple facets of health but, given current evidence, are unable to specify a level of vitamin D intake that is likely to be safe, effective, and fully beneficial for all Americans.


Instead of a careful, science-minded conclusion that meets the painfully conservative demands of crafting broad public policy, the committee instead chose to dogmatically pull the discussion back to the 1990s, ignoring the flood of compelling evidence that suggests that vitamin D is among the most important public health issues of the age.

Believe it or not, this new, though anemic, RDA represents progress: It's a (small) step farther down the road towards broader recognition and acceptance that higher intakes (or skin exposures) to achieve higher vitamin D levels are good for health.

My view: Vitamin D remains among the most substantial, life-changing health issues of our age. Having restored 25-hydroxy vitamin D levels in over 1000 people, I have no doubt whatsoever that vitamin D achieves substantial benefits in health with virtually no downside, provided 25-hydroxy vitamin D levels are monitored.

Coronary calcium: Cause or effect?

Here's an interesting observation made by a British research group.

We all know that coronary calcium, as measured by CT heart scans, are a surrogate measure of atherosclerotic plaque "burden," i.e., an indirect yardstick for coronary plaque. The greater the quantity of coronary calcium, the higher the heart scan "score," the greater the risk for heart attack and other unstable coronary syndromes that lead to stents, bypass, etc.

But can calcium also cause plaque to form or trigger processes that lead to plaque formation and/or instability?

Nadra et al show, in an in vitro preparation, that calcium phosphate crystals are actively incorporated into inflammatory macrophages, which then trigger a constellation of inflammatory cytokine release (tumor necrosis factor-alpha, interleukins), fundamental processes underlying atherosclerotic plaque formation and inflammation.

Here's the abstract of the study:
Proinflammatory Activation of Macrophages by Basic Calcium Phosphate Crystals via Protein Kinase C and MAP Kinase Pathways:

A Vicious Cycle of Inflammation and Arterial Calcification?


Basic calcium phosphate (BCP) crystal deposition underlies the development of arterial calcification. Inflammatory macrophagescolocalize with BCP deposits in developing atherosclerotic lesionsand in vitro can promote calcification through the release of TNF alpha. Here we have investigated whether BCP crystals can elicit a proinflammatory response from monocyte-macrophages.BCP microcrystals were internalized into vacuoles of human monocyte-derived macrophages in vitro. This was associated with secretion of proinflammatory cytokines (TNF{alpha}, IL-1ß and IL-8) capable of activating cultured endothelial cells and promoting capture of flowing leukocytes under shear flow. Critical roles for PKC, ERK1/2, JNK, but not p38 intracellular signaling pathways were identified in the secretion of TNF alpha, with activation of ERK1/2 but not JNK being dependent on upstream activation of PKC. Using confocal microscopy and adenoviral transfection approaches, we determined a specific role for the PKC-alpha isozyme.

The response of macrophages to BCP crystals suggests that pathological calcification is not merely a passive consequence of chronic inflammatory disease but may lead to a positive feed-back loop of calcification and inflammation driving disease progression.



This observation adds support to the notion that increasing coronary calcium scores, i.e., increasing accumulation of calcium within plaque, suggests active plaque. As I say in Track Your Plaque, "growing plaque is active plaque." Active plaque means plaque that is actively growing, inflamed and infiltrated by inflammatory cells like macrophages, eroding its structural components, and prone to "rupture," i.e., cause heart attack. Someone whose first heart scan score is, say, 100, followed by another heart scan score two years later of 200 is exposed to sharply increasing risk for cardiovascular events which may, in part, be due to the plaque-stimulating effects of calcium.

Conversely, reducing coronary calcium scores removes a component of plaque that would otherwise fuel its growth. So, people like our Freddie, who reduced his heart scan score by 75%, can be expected to enjoy a dramatic reduction of risk for cardiovascular events.

Less calcium, less plaque to rupture, less risk.

Wheat one-liners

If you're having difficulty convincing a loved one or someone else that wheat should be eliminated from the human diet, here are some useful one-liners to use:

Wheat makes your boobs big.
(This is true. Priceless for women to use on their husbands.)

Wheat causes dementia.
(And confirmed on examination of brain tissue at autopsy. Yes, autopsy.)

Wheat makes you look pregnant.
(The visceral fat of a wheat belly does a darn good imitation of a near-term infant.)

The first sign of wheat intolerance can be wetting your pants.
(Cerebellar ataxia, i.e., destruction and atrophy of the cerebellum, caused by wheat leads to loss of coordination and bladder control. Average age of onset: 53 years old.)

White flour bad, whole grain better; just as Marlboros are bad, Salems are better.
(The flawed syllogism that led to the "eat more healthy whole grain" colossal blunder.)

Wheat is the only food with its very own mortality rate.
(Celiac disease, osteoporotic hip fractures, and the neurologic diseases triggered by wheat can be fatal.)

"Wheat" is no longer wheat; it's the dwarf mutant that came from genetics research in the 1960s.
(Over 99% of all wheat today comes from the 18-inch tall dwarf mutant.)

Wheat increases blood sugar higher than nearly all other foods.
(Higher than Milky Way bars, higher than Snickers bars, higher than table sugar.)


There you have it: A full arsenal of one-liners to shoot at your husband, wife, or friend when they roll their eyes at your refusal to consume this thing called "wheat."

The happy homeotherm

If you were a "cold blooded" poikilotherm unable to regulate internal body temperature, you would have to sun yourself on rocks to raise your body temperature, just like turtles and snakes. When it got cold, your metabolic rate would slow and you might burrow into the mud to hide.

You and I, however, are homeotherms, terrestrial animals able to regulate our own internal body temperature. Principal responsibility for keeping your body temperature regulated falls with the thyroid gland, your very own thermoregulatory "thermostat."

But internal body temperature, even in a homeotherm, varies with circadian rhythm: Highest temperature occurs in the early evening around 8 p.m.; the low temperature nadir occurs at around 4 a.m.

The notion that normal human temperature is 98.6 degrees Fahrenheit is a widely-held fiction, a legacy of the extraordinary experience of 19th century German physician, Carl Reinhold August Wunderlich, who claims to have measured temperatures of one million people using his crude, uncalibrated thermometer to obtain axillary (armpit) body temperatures.

Dr. Broda Barnes was a 20th century American proponent of using the nadir body temperature to gauge thyroid function. Like Wunderlich, Barnes also used axillary temperatures.

Modern temperature assessments have employed radiotransmitting thermistors that are swallowed, with temperatures tracked as the thermistor travels through the stomach, duodenum, small intestine, large intestine, rectum, then peek-a-boos back out. Such internal "core temperature" assessments have shown that:

--Axillary temperatures do not track with internal core temperatures very well, often veering off course due to external factors.
--Axillary temperatures are subject to ambient temperatures, such as room temperature, and are affected by clothing.
--Axillary temperatures are more susceptible to physical activity, e.g., increased with exercise or physical work.

Even right vs. left axillary temperatures have been shown to vary up to 2 degrees Fahrenheit.

Studies such as this demonstrate that normal oral temperature upon arising is around 97.2-97.3 degrees Fahrenheit. While we lack data correlating thyroid function with circadian temperature variation, the a.m. nadir does indeed, as Dr. Barnes originally suggested, seem to track thyroid status quite well: lower with hypothyroidism, higher with normal or hyperthyroidism.

I have been using 97.3 degrees F orally as the cutoff for confirming or uncovering thyroid dysfunction, particularly when symptoms or blood tests (TSH, free T3, free T4) are equivocal, a value that has held up well in the majority of cases. I find it helpful when, for instance, someone complains of cold hands and feet and has normal TSH (1.5 mIU/L or less in my view) but low free T3. An a.m. oral temperature of, say, 95.7 degrees F, suggests that there will be a favorable response to T3 supplementation. And it nearly always plays out that way.

Wouldn't it be interesting to know if there was insight into thyroid status provided by also examining the circadian behavior of temperature (e.g., height or timing of the peak)?

Statin buster?

Merck recently reported preliminary results with its drug-in-development, anacetrapib.

After six months of treatment, participants showed:

LDL cholesterol was reduced from 81 mg/dl to 45 mg/dl in those taking anacetrapib, and from 82 mg/dl to 77 mg/dl in the placebo group.

HDL increased from 41 mg/dl to 101 mg/dl in the drug group, from 40 mg/dl to 46 mg/dl in those on placebo.

As you'd expect, the usual line-up of my colleagues gushed over the prospects of the drug, salivating over new speaking opportunities, handsomely-paid clinical "research" trials, and plenty of nice trips to exotic locales.

Anacetrapib is a cholesteryl-ester transfer protein inhibitor, or CETP inhibitor, much like its scrapped predecessor, torcetrapib . . . you know, the one that went down in flames in 2006 after 60% excess mortality occurred in people taking the drug compared to placebo. The hopes of many investors and Pfizer executives were dashed with torcetrapib's demise. The data on torcetrapib's lipid effects were as impressive as Merck's anacetrapib.

These drugs block the effects of the CETP enzyme, an enzyme with complex effects. Among CETP's effects: mediating the "heteroexchange" of triglycerides from triglyceride-rich VLDL particles that first emerge from the liver for cholesterol from LDL particles. This CETP-mediated process enriches LDL particles with triglycerides, which then make LDL a target for action by another enzyme, hepatic lipase, that removes triglycerides. This yields a several nanometer smaller LDL particle, now the number one most common cause of heart disease in the U.S., thanks to conventional advice to cut fat intake and increase consumption of "healthy whole grains."

With effects like this, anacetrapib, should it hold up under the scrutiny of FDA-required trials and not show the same mortality-increasing effects of torcetrapib, will be a huge blockbuster for Merck if release goes as scheduled in 2015. It will likely match or exceed sales of any statin drug. Statin drugs have achieved $27 billion annual sales, some of it deserved. Anacetrapib will likely handily match or exceed Lipitor's $12 billion annual revenue.

More than increasing HDL, CETP inhibition is really a strategy to reduce small LDL particles.

As with many drugs, there are natural means to achieve similar effects with none of the side-effects. In this case, similar effects to CETP inhibition, though with no risk of heightened mortality, is . . . elimination of wheat, in addition to an overall limitation of carbohydrate consumption. Not just low-carb, mind you, but wheat elimination on the background of low-carb. For instance, eliminate wheat products and limit daily carbohydrate intake to 50-100 grams per day, depending on your individual carbohydrate sensitivity, and small LDL drops 50-75%. HDL, too, will increase over time, not as vigorously as with a CETP inhibitor, but a healthy 20-30% increase, more with restoration of vitamin D.

Eliminating wheat and adjusting diet to ratchet down carbs is, of course, cheap, non-prescription, and can be self-administerd, criteria that leave the medical world indifferent. But it's a form of "CETP inhibition" that you can employ today with none of the worries of a new drug, especially one that might share effects with an agent with a dangerous track record.

Why does wheat cause arthritis?

Wheat causes arthritis.

Before you say "What the hell is he saying now?", let me connect the dots on how this ubiquitous dietary ingredient accelerates the path to arthritis in its many forms.

1) Wheat causes glycation--Glycation is glucose-modification of proteins in the body that occurs when blood glucose exceeds 100 mg/dl. Cartilage cells are especially susceptible to glycation. The cartilage cells you had at age 18 are the very same cartilage cells you have at age 60, since they lack the ability to reproduce and repair themselves. Proteins in cartilage are highly susceptible to glycation, which makes them stiff and brittle. Stiff, brittle cartilage loses its soft, elastic, lubricating function. Damaged cartilage cells don't regenerate nor produce more protective proteins. This allows destruction of cartilage tissue, inflammation, and, eventually, bone-on-bone arthritis.

Because wheat, even whole wheat, sends blood sugar higher than almost all other foods, from table sugar to Snickers bars, glycation occurs after each and every slice of toast, every whole wheat bagel, every pita wrap.

2) Wheat is acidifying--Humans are meant to consume a diet that is net alkaline. While hunter-gatherers who consume meat along with plentiful vegetables and fruits live a net alkaline diet (urine pH 7 to 9), modern humans who consume insufficient vegetables and too much grain (of which more than 90% is usually wheat) shift the body towards net acid (urine pH 5 to 7). Wheat is The Great Disrupter, upsetting the normal pH balance that causes loss of calcium from bones, resulting in decalcification, weakness, arthritis and osteoporotic fractures.

3) Wheat causes visceral fat--The extravagant glucose-insulin surges triggered by wheat leads to accumulation of visceral fat: wheat belly.

Visceral fat not only releases inflammatory mediators like tumor necrosis factor and various interleukins, but is also itself inflamed. The inflammatory hotbed of the wheat belly leads to inflammation of joint tissues. This is why overweight and obese wheat-consuming people have more arthritis than would be explained by the burden of excess weight: inflammation makes it worse. Conversely, weight loss leads to greater relief from arthritis pain and inflammation than would be explained by just lightening the physical load.

We need a name for this wheat effect. How about "bagel bones"?

Why do morphine-blocking drugs make you lose weight?

Naloxone (IV) and naltrexone (oral) are drugs that block the action of morphine.

If you were an inner city heroine addict and got knifed during a drug deal, you'd be dragged into the local emergency room. You're high, irrational, and combative. The ER staff restrain you, inject you with naloxone and you are instantly not high. Or, if you overdosed on morphine and stopped breathing, an injection of naloxone would reverse the effect immediately, making you sit bolt upright and wondering what the heck was going on.

So what do morphine-blocking drugs have to do with weight loss?

An odd series of clinical studies conducted over the past 40 years has demonstrated that foods can have opiate-like properties. Opiate blockers, like naloxone, can thereby block appetite. One such study demonstrated 28% reduction in caloric intake after naloxone administration. But opiate blocking drugs don't block desire for all foods, just some.

What food is known to be broken down into opiate-like polypeptides?

Wheat. On digestion in the gastrointestinal tract, wheat gluten is broken down into a collection of polypeptides that are released into the bloodstream. These gluten-derived polypeptides are able to cross the blood-brain barrier and enter the brain. Their binding to brain cells can be blocked by naloxone or naltrexone administration. These polypeptides have been named exorphins, since they exert morphine-like activity on the brain. While you may not be "high," many people experience a subtle reward, a low-grade pleasure or euphoria.

For the same reasons, 30% of people who stop consuming wheat experience withdrawal, i.e., sadness, mental fog, and fatigue.

Wouldn't you know that the pharmaceutical industry would eventually catch on? Drug company startup, Orexigen, will be making FDA application for its drug, Contrave, a combination of naltrexone and the antidepressant, buproprion. It is billed as a blocker of the "mesolimbic reward system" that enhances weight loss.

Step back a moment and think about this: We are urged by the USDA and other "official" sources of nutritional advice to eat more "healthy whole grains." Such advice creates a nation of obese Americans, many the unwitting victims of the new generation of exorphin-generating, high-yield dwarf mutant wheat. A desperate, obese public now turns to the drug industry to provide drugs that can turn off the addictive behavior of the USDA-endorsed food.

There is no question that wheat has addictive properties. You will soon be able to take a drug to block its effects. That way, the food industry profits, the drug industry profits, and you pay for it all.

Heart scan tomfoolery 2

In the last Heart Scan Blog post, I discussed the significance of the apparent discrepancy between Steve's heart scan score and volume score. This post addresses his second question, also a FAQ about heart scan scores.

Steve noted that his second scan compared to his first showed:

- Left Main volume went up from 22.4 to 35.6
- LAD went down from 95.2 to 91.3
- LCX volume went down from 23.2 to 0
- RCA volume went up from 0 to 9.3

So there are apparent divergences in behavior in the left main that increased and both LAD (left anterior descending) and LCX (left circumflex) that decreased.

The explanation is simple: When heart scans are "scored," they are viewed in horizontal "slices." When the heart is viewed as horizontal slices, the LAD and LCX originate from the common left main stem. In other words, it's like a tree with the left mainsteam representing the trunk, the LAD and LCX representing two main branches.

Plaque can form, obviously, in all three arteries, but it can do so by starting in the left main, for instance, and extending into either the LAD or LCX, or both. The left main plaque can therefore bridge any 2 or all 3 arteries.

When the plaque is "scored" by taking the computer mouse and circling the calcified plaque in question (to allow the computer program to generate the calcium score and volume score of that particular plaque), the plaque that may extend from left main into the LAD and/or LCX might be labeled "left main," or it might be labeled "LAD" or "LCX." There is no reliable way to "dissect" apart the plaque into the three arteries, since the plaque is coalescent and continuous. So the scoring technologist or physician simply arbitrarily declares the artery "LAD," for instance.

The problem comes when two different interpretation methods are used: Perhaps it's a new technologist or physician, or there was no attention paid to how the previous scan was read. One reader calls it "left main" and the next calls it "LCX."

So the apparent discrepancy has to do with flaws in the methods of segregating plaque location, as well as inattention to scoring techniques. The total score, however, remains unaffected.

Nonetheless, Steve has enjoyed a modest reduction in the score of the left main/LAD/LCX from his original 140.8 down to a second left main/LAD/LCX score of 126.9.

The right coronary artery (RCA), however, is not subject to this difficulty and Steve score shows a modest increase in score. (Why the divergent behavior between left main/LAD/LCX and RCA? There is no clear explanation for this, unfortunately.)

All in all, the news for Steve is good: He achieved these results on his own using nutritional techniques. Because he, in all practicality, stopped the progression of his heart scan score and avoided the "natural" rate of increase of 30% per year, all he needs to do is "tweak" his program a bit to achieve reversal, i.e., reduction of score.


Here's an image from another previous Heart Scan Blog post (about the relationship of osteoporosis and coronary disease) that shows such a plaque that starts in the left mainstem yet extends into both the LAD and LCX:

Heart scan tomfoolery

Heart Scan Blog reader, Steve, sent these interesting questions about his heart scan experience. (I sometimes forget that this blog is called "The Heart Scan Blog" and was originally--several years ago--meant to discuss heart scans. It has evolved to become a much broader conversation.)

The answers are a bit lengthy, so I'll tackle Steve's questions in two parts, the second in another blog post.

Dr. Davis,

I had a heart scan last year. The score was 96. While not a horrible score, it
was a wake up call, and I changed my lifestyle.

I had another scan this year and the heart scan score went up to 105, but the
volume score went down from 141 to 136.

The report I received said this:

'The calcium volume score is less in the current study as compared with the
original or reference study. This is an excellent coronary result and indicates
that there has been a net decrease in coronary plaque burden. The current
prevention program is very effective and should be continued.'

This is all well and good, but I have two questions:

1. Am I really going in the right direction even though the heart scan score
went up 9%?

2. Here are results that make no sense to me:
- Left Main volume went up from 22.4 to 35.6
- LAD went down from 95.2 to 91.3
- LCX volume went down from 23.2 to 0
- RCA volume went up from 0 to 9.3

Why would there be so much variation from year to year, and why would the plaque
move from site to site?

Steve


Questions like Steve's come up with some frequency, so I thought it would be worthwhile to discuss in a blog post.

First of all, the conventional heart scan score, or "calcium score" or "Agatston score" (after Dr. Arthur Agatston, developer of the simple algorithm for calcium scoring, as well as South Beach Diet fame), is the product of the area of the plaque in a single CT "slice" image
multiplied by a density coefficient, i.e., a number ranging from 1 to 4 that grades the x-ray density of the plaque. (1 is least dense; 4 is most dense.) A density coefficient of 1 therefore signifies some calcium within plaque, with higher density coefficients signifying increasing calcium content and density. Incidentally, "soft" plaque, i.e., non-calcified, would fall in the less than 1 range, even the negative range (fatty tissue within plaque).

The volume, or "volumetric," score is the brainchild of Drs. Paulo Raggi and Traci Callister, who expressed concern that, if we cause plaque to shrink in volume, the density coefficient used to calculate the calcium score would increase (since they believed that calcium could not be reduced, contrary to our Track Your Plaque experience, thereby leading to misleading results. They therefore developed an algorithm that did not rely on density coefficients, but used the same two-dimensional area obtained in the standard heart scan score, but replaced the density coefficient with a (mathematically interpolated) vertical axis (z-axis) measure of plaque "height." This 3-dimensional volumetric value therefore provided a method to generate a measure of calcium volume. In their original publication, the volume score proved more reproducible than the standard calcium score. This way, any reduction in plaque volume would not be influenced by the misleading effects of calcium density, but reflect a real reduction in volume.

Callister and Raggi's study also highlighted that calcium scoring in any form is subject to variability. Back in 1998 (when their study was published), there was a bit more variation than today due to the image acquisition methods used. But, even today, there is about 9% variation in scoring even if performed repeatedly (with less percentage variation the higher the score).

Unfortunately, volume scoring never caught on and the calcium score has been the most commonly used value by most heart scan centers and in most clinical studies. And, in all practicality, the two values nearly always track together: When calcium score increases, volume score increases in tandem; when calcium score decreases, volume score decreases in tandem.

Steve is therefore an exception to the general observation that calcium score and volume score travel together. Steve's calcium score increased, while his volume score decreased. From the above discussion, you can surmise a few things about Steve's experience:"

1) In all likelihood, the changes in both calcium score and volume score could simply be due to variability, i.e., variation in the placement of his body on the scan table, variation in position of the heart, variation in data acquisition, etc. There is a high likelihood that neither value changed; both are essentially unchanged.

2) If the changes are not due to scan variability, but are real, then it could be that the calcified plaque is reduced in volume but increased in density. If true, this is probably still a favorable phenomenon, since plaque volume is a powerful predictor of coronary "events" and an increase in plaque density is likely a benign phenomenon. It would also raise questions about the adequacy of vitamin D and vitamin K2 status, both major control factors over calcium deposition and metabolism.

So, in all likelihood, Steve's apparent discrepant results are modest good news, especially since calcium scores can ordinarily be expected to increase at the rate of 30% per year if no action is taken. Experiencing no change in score, calcium or volumetric, carries a very excellent prognosis, with risk for heart attack approaching zero. (I'm impressed that Steve accomplished this on his own, something the majority of my colleagues haven't the least bit of interest doing.)

Part 2 of Steve's question will be tackled in a separate post.
Do heart scans cause cancer?

Do heart scans cause cancer?

Another in a series of data extrapolations that attempt to predict long-term cancer risk from medical radiation exposure was published in the July 13, 2009 Archives of Internal Medicine, viewable here.

Over the years, I've fussed about the radiation dose used by some centers for CT heart scans. (Note: I'm talking about CT heart scans, not CT coronary angiograms, an entirely different test with different radiation exposure.) In the "old" days, when electron-beam devices (EBT) were the best on the block, the old single-slice CT scanners (the predecessor of the current 64-slice MDCT scanners) exposed patients to ungodly quantities of radiation, while the EBT devices required very small quantities (0.5 mSv or about the equivalent of 4 standard chest x-rays or one mammogram).

But CT technology has advanced considerably. While EBT has been phased out (although it was an exceptional technology, GE acquired the small California manufacturer, then promptly scrapped the operation; you can guess why), multi-detector CT (MDCT) technology has improved in speed, image quality, and radiation exposure.

While it has improved, radiation exposure still remains an issue. The authors of the study applied the scanning protocols used at three hospitals and those in several CT heart scan studies, then calculated radiation exposure. They found a more than ten-fold range of exposure, from 0.8 mSv to 10.5 mSv. (All scanners were MDCT, none EBT.)

That's precisely what I've been worrying about: In the rapid rush to develop new devices, radiation exposure has often been a neglected issue. While some scan centers do an excellent job and take steps to minimize exposure, others barely lift a finger and consequently expose their patients to unnecessary radiation.

However, it's not as bad as it sounds. For one, the study included 16-slice MDCT scanners, a scanner type that I warned people to not use because of radiation. On the current most popular 64-slice devices, much lower radiation exposure is possible, on the order of 0.8-1.2 mSv routinely--if the center takes the effort.

This study, while eye-opening, will achieve some good: CT heart scans are here to stay. But the day-to-day practice of heart scanning should be:

1) standardized
2) conducted with radiation exposure as low as possible, preferably <0.8 mSv


To read more about this issue, below I've reprinted a 2007 full Track Your Plaque Special Report, CT Heart Scans and Radiation: The Real Story.




CT heart scans and radiation: The real story

“My personal opinion is that many patients today who are receiving multiple CT scans may well be getting at least comparable doses to subjects that have now developed malignancies from x-ray radiation received in the 1930s and '40s. And, similar to those days when the doses were unknown, the dose that patients receive today over a course of years of multiple CT scans is also completely unknown . . .

“I recommend that all healthcare providers become familiar with the concept that 1 in 1000 CT studies of the chest, abdomen, or pelvis may result in cancer.”


Richard C. Semelka, MD
Professor and Vice Chairman, Department of Radiology
University of North Carolina–Chapel Hill



Is this just hype to generate headlines? Or is the truth buried in the enormous marketing clout of the medical device industry, among which the imaging device manufacturers reign supreme?

It’s been over 110 years since radiation was first used for medical imaging. Over those years, it has had its share of misadventures.

In the 1930s and 1940s, before the dangers of radiation were recognized, shoe shoppers had shoes fitted using an x-ray device of the foot to assess fit. High doses of radiation were used to shrink enlarged tonsils and extinguish overactive thyroid glands. Attitudes towards radiation were so lax that doctors commonly permitted themselves to be exposed without protection day after day, year after year, until an unexpected rise in blood cancers like leukemia was observed. As recently as the 1970s and 1980s, cancers like Hodgkins’ disease were treated with high doses of radiation, also leading to radiation-induced diseases decades later.

Not all radiation is bad. Radiation can also be used as a therapeutic tool and even today remains a useful and reasonably effective method to reduce the size, sometimes eliminate, certain types of cancer. Forty percent of people with cancer now receive some form of radiation as part of their treatment (Ron E 2003).


Just how much does medical radiation add to our exposure?

Estimates vary, but most experts estimate that medical imaging provides approximately 15% of total lifetime exposure. In other words, radiation exposure from medical imaging is simply a small portion of total exposure that develops over the years of life. Exposure can be much higher, however, in a specific individual who undergoes repeated radiation imaging or treatment of one sort or another.

For all of us, exposure to medical radiation is part of lifetime exposure from multiple sources, added to the radiation we receive from the world around us. Just by living on earth, we are exposed to radiation from space and naturally-occurring radioactive compounds, and receive somewhere around 3.0 mSv per year (U.S. Nuclear Regulatory Commission). (Doses for radiation exposure are commonly expressed in milliSieverts, mSv, a measure that reflects whole-body radiation exposure.) People living in high-altitude locales like Colorado get exposed to an additional 30–50% ambient radiation (1.0–1.5 mSv more per year).

Much of the information on radiation exposure comes from studies like the Life Span Study that, since 1961, has tracked 120,000 Japanese exposed to radiation from the atomic bombs dropped in 1945 (Preston DL et al 2003). Although regarded as a high-dose exposure study for obvious reasons, there are actually thousands of people in this study who were exposed to lesser quantities of radiation (because of distance from the bomb sites) who still display a “dose-response” increased risk for cancer many years later in life. Radiation exposures of as little as 5–20 mSv showed a slight increase in lifetime risk.

Occupational and excessive medical exposure to radiation also provides a “laboratory” to examine radiation risk. Miners exposed to radon gas; patients exposed to the imaging agent, Thorotrast, containing radioactive isotope thorium dioxide and used as an x-ray contrast agent in the 1930s and 1940s and possesses the curious property of lingering in the body for over 30 years after administration; radium injections administered between 1945 and 1955 to treat diseases like ankylosing spondylitis and tuberculosis, all provide researchers an opportunity to study the long-term effects of various types of radiation exposure over many years (Harrison JD et al 2003).

The excess exposure of workers and several hundred thousand nearby residents to the Mayak nuclear plant in Russia has also revealed a “dose-response” relationship, with increasing exposure leading to more cancers, including leukemia and solid cancers of the bone, liver, and lung (Shilnikova NS et al 2003). Nuclear waste released into the Techa river between 1948 and 1956 contaminated drinking water used by over 100,000 Russians. A plant explosion in 1957 also released an excess of radiation into the atmosphere, yielding exposure via inhalation. Some sources estimate that at least 272,000 people have been affected by radiation from the Mayak plant. This unfortunate situation has, however, yielded plenty of data on radiation exposure and its long-term effects.

It’s also been known for several decades that people who receive therapeutic radiation for treatment of cancer, even with the reduced doses now employed, are subject to increased risk of a second cancer consequent to the radiation treatment.

From experiences like this, radiation experts estimate that an exposure of 10 mSv increases a population’s risk for cancer by 1 in 1000 (Semelka RC et al 2007).

This question was recently thrust into the spotlight with publication of a study from Columbia University in New York suggesting that a 20-year old woman would be exposed to a lifetime risk of cancer as high as 1 in 143 consequent to the radiation received during a CT coronary angiogram. (Important note: This was estimated risk from a CT coronary angiogram, not a simple heart scan that we advocate for the Track Your Plaque program.) The risk at the low end of the spectrum would be in an 80-year old man (because of the shorter period of time to develop cancer), with a risk of 1 in 5017. If “gating” to the EKG is added (which many scan centers do indeed perform nowadays), risk for a 60-year old woman is estimated at 1 in 715; risk for a 60-year old male, 1 in 1911 (Einstein AJ et al 2007). This study generated some criticism, since it did not directly involve human subjects, but used “phantoms” or x-ray dummies to simulate x-ray exposure. Nonetheless, the point was made: CT coronary angiograms in current practice do indeed expose the patient to substantial quantities of radiation, sufficient to pose a lifetime risk of cancer.


The media frenzy

The NY Times ran an article called With Rise in Radiation Exposure, Experts Urge Caution on Tests in which they stated:

"According to a new study, the per-capita dose of ionizing radiation from clinical imaging exams in the United States increased almost 600 percent from 1980 to 2006. In the past, natural background radiation was the leading source of human exposure; that has been displaced by diagnostic imaging procedures, the authors said."

“This is an absolutely sentinel event, a wake-up call,” said Dr. Fred A. Mettler Jr., principal investigator for the study, by the National Council on Radiation Protection. “Medical exposure now dwarfs that of all other sources.”

Radiation is a widely used imaging tool in medicine. Although CT scans of the brain, bones, chest, abdomen, and pelvis account for only 5% of all medical radiation procedures, they are responsible for nearly 50% of medical radiation used. It’s been known for years that increasing radiation exposure increases cancer risk over many years, but the boom of newer, faster devices that provide more detailed images has opened the floodgates to expanded use of CT scanners.

But before we join in the hysteria, let's first take a look at exposure measured for different sorts of tests:


Typical effective radiation dose values for common tests

Computed Tomography

Head CT 1 – 2 mSv
Pelvis CT 3 – 4 mSv
Chest CT 5 – 7 mSv
Abdomen CT 5 – 7 mSv
Abdomen/pelvis CT 8 – 11 mSv
Coronary CT angiography 5 – 12 mSv


Non-CT

Hand radiograph Less than 0.1 mSv
Chest radiograph Less than 0.1 mSv
Mammogram 0.3 – 0.6 mSv
Barium enema exam 3 – 6 mSv
Coronary angiogram 5 – 10 mSv
Sestamibi myocardial perfusion (per injection) 6 – 9 mSv
Thallium myocardial perfusion (per injection) 26 – 35 mSv

Source: Cynthia H. McCullough, Ph.D., Mayo Clinic, Rochester, MN


A plain, everyday chest x-ray, providing less than 0.1 mSv exposure, provides about the same quantity of radiation exposure as flying in an airplane for four hours, or the same amount of radiation from exposure to our surroundings for 11–12 days. Similar exposure arises from dental x-rays.

If you have a heart scan on an EBT device, then your exposure is 0.5-0.6 mSv, roughly the same as a mammogram or several standard chest x-rays.

With a heart scan on a 16- or 64-slice multidetector device, exposure is ideally around 1.0-2.0 mSv, about the same as 2-3 mammograms, though dose can vary with this technology depending on how it is performed (gated to the EKG, device settings, etc.)

CT coronary angiography presents a different story. This is where radiation really escalates and puts the radiation exposure issue in the spotlight. As Dr. Cynthia McCullough's chart shows above, the radiation exposure with CT coronary angiograms is 5-12 mSv, the equivalent of 100 or more chest x-rays or 20 mammograms. Now, that's a problem.

The exposure is about the same for a pelvic or abdominal CT. The problem is that some centers are using CT coronary angiograms as screening procedures and even advocating their use annually. This is where the alarm needs to be sounded. These tests, as wonderful as the information and image quality can be, are not screening tests. Just like a pelvic CT, they are diagnostic tests done for legitimate medical questions. They are not screening tests to be applied broadly and used year after year.

It’s also worth giving second thought to any full body scan you might be considering. These screening studies include scans of the chest, abdomen, and pelvis. These scans, performed for screening, expose the recipient to approximately 10 mSv of radiation (Radiological Society of North American, 2007). Debate continues on whether the radiation exposure is justified, given the generally asymptomatic people who generally undergo these tests.

Always be mindful of your radiation exposure, as the NY Times article rightly advises. However, don't be so frightened that you are kept from obtaining truly useful information from, for instance, a CT heart scan (not angiography) at a modest radiation cost.


Heart scans, CT coronary angiograms and the future

Unfortunately, practicing physicians and those involved in providing CT scans are generally unconcerned with radiation exposure. The majority, in fact, are entirely unaware of the dose of radiation required for most CT scan studies and unaware of the cancer risk involved. It is therefore up to the individual to insist on a discussion of the type of scanner being used, the radiation dose delivered (at least in general terms), the necessity of the test, alternative methods to obtain the same diagnostic information, all in the context of lifetime radiation exposure.

Our concerns about radiation exposure all boil down to concern over lifetime risk for cancer, a disease that strikes approximately 20% of all Americans. Many factors contribute to cancer risk, including obesity, excessive saturated fat intake, low fiber intake, lack of vitamin D, repeated sunburns, excessive alcohol use, smoking, exposure to pesticides and other organochemicals, asbestos and other industrial exposures, electromagnetic wave exposure, and genetics. Radiation is just one source of risk, though to some degree a controllable one.

Some people, on hearing this somewhat disturbing discussion, refuse to ever have another medical test requiring radiation. That’s the wrong attitude. It makes no more sense than wearing lead shielding on your body 24 hours a day to reduce exposure from the atmosphere. Taken in the larger context of life, radiation exposure is just one item on a list of potentially harmful factors.

It is, however, worth some effort to minimize radiation exposure over your lifetime, particularly before age 60, and by submitting to high-dose testing only when truly necessary, or when the potential benefits outweigh the risks. Thus, with heart scans and CT coronary angiography, some thought to the potential benefits of knowing your score or the information gained from the CT angiogram need to be considered before undergoing the test. Often the practical difficulty, of course, is that your risk for heart disease simply cannot be known until after the test.

In our view, in the vast majority of instances a simple CT heart scan can serve the simple but crucial role of quantifying risk for heart attack and atherosclerotic plaque. CT heart scans yield this information with less than a tenth of the radiation exposure of a CT coronary angiogram. In people without symptoms and a normal stress test, there is rarely a need for CT coronary angiography with present day levels of radiation exposure. Perhaps as technology advances and the radiation required to generate images is reduced, then we should reconsider.

Early experiences are suggesting that the newest 256-slice scanners, now being developed but not yet available, will cut the dose exposure of 64-slice CT angiograms in half (from 27.8 mSv to 14.1 mSv in a recent Japanese study). The 256-slice scanners will allow scanning that is faster over a larger area in a given period of time.

Thankfully, the scanner manufacturers are increasingly sensitive to the radiation issue and have been working on methods to reduce radiation exposure. However, it still remains substantial.


References:
Einstein AJ, Henzlova MJ, Rajagopalan S. Estimating risk of cancer associated with radiation exposure from 64-slice computed tomography coronary angiography. JAMA 2007 Jul 18;298(3):317–323.

Harrison JD, Muirhead CR. Quantitative comparisons of cancer induction in humans by internally deposited radionuclides and external radiation. Int J Radiat Biol 2003 Jan;79(1):1–13.

Hausleiter J, Meyer T, Hadamitzyky M et al. Radiation Dose Estimates From Cardiac Multislice Computed Tomography in Daily Practice: Impact of Different Scanning Protocols on Effective Dose Estimates. Circulation 2006;113:1305–1310.

Kalra MK, Maher MM, Toth TL, Hamberg LM, Blake MA, Shepard J, Saini S. Strategies for CT radiation dose optimization. Radiology 2004;230:619–628.

Mayo JR, Aldrich J, Müller NL. Radiation exposure at chest CT: A statement of the Fleischner Society. Radiology 2003; 228:15–21.

Mori S, Nishizawa K, Kondo C, Ohno M, Akahane K, Endo M. Effective doses in subjects undergoing computed tomography cardiac imaging with the 256-multislice CT scanner. Eur J Radiol 2007 Jul 10; [Epub ahead of print].

Preston DL, Pierce DA, Shimizu Y, Ron E, Mabuchi K. Dose response and temporal patterns of radiation-associated solid cancer risks. Health Phys 2003 Jul;85(1):43–46.

Ron E. Cancer risks from medical radiation. Health Phys 2003 Jul;85(1):47–59.

Shilnikova NS, Preston DL, Ron E et al. Cancer mortality risk among workers at the Mayak nuclear complex. Radiation Res 2003 Jun;159(6):787–798.

Semelka RC, Armao DM, Elias J Jr, Huda W. Imaging strategies to reduce the risk of radiation in CT studies, including selective substitution with MRI. J Magn Reson Imaging 2007 May;25(5):900–9090.


Copyright 2007, Track Your Plaque.

Comments (3) -

  • Anne

    7/16/2009 11:38:08 AM |

    I remember those x-ray devices at the shoe store. It was fun looking at the bones in my feet. I also got to play with mercury when I visited an amateur chemist in the neighborhood. He would pour a little mercury in our hands and we would roll it around.

    I wonder what my radiation dose was in the years I was having coronary blockage. I went through 6 coronary caths - 4 were stents. Then I had bypass. Yearly mammograms and dental xrays. Bone density testing every 3 yrs. There are websites where one can add up all their radiation exposure including and estimate of environmental exposure too.

  • Brate

    7/17/2009 5:46:33 AM |

    Sometimes for a patient, it is more a comfort than the technology which we generally try to run for. And does it really matter for a heart patient having an artery blockage or having their valves dismantled that what amount of radiation they are incurring. The question is, is there any feasible reason to question the ability of such tests. These tests have been a boon for both doctors to help them diagnose the problems, and for the patients to help them have a better life. But yes, advancements in the technology should be a possible solution. But it’s not always the best solution to the problem. Advancements in the technology have greatly diversified the perception of people towards healthcare. People used to be frightened when they were prescribed for any test, or were forwarded to hospital. But now, because of the amount of advancements in technology and also the amount of soft-care has changed the age-old perception of healthcare. Now, people feel free to have a medical checkup. The amount of comfort they feel though surrounded by some most complex machineries in the world is the achievement that technology has got. The concepts like concierge medicine and Boutique medical practice has revolutionized the basic fundamentals of healthcare. Many hospitals and medical service providers: Cleveland clinic, Mayo Clinic, Elite health, to name a few, have completely revolutionized the concept of older concierge medicine. The amount of care added with treatment makes a trip to hospital a better journey. All the requirements starting from transportation, stay in the hotel, appointments, etc are one phone away with these concierge plans. Increasingly people are opting for concierge facilities. The overall information regarding concierge plan is described here:
    https://www.clevelandclinic.org/thoracic/Concierge/Concierge.htm
    http://www.mayoclinic.org/travel-rst/concierge-services.html
    http://www.elitehealth.com/concierge_healthcare.php

  • buy jeans

    11/3/2010 4:57:15 PM |

    However, it's not as bad as it sounds. For one, the study included 16-slice MDCT scanners, a scanner type that I warned people to not use because of radiation. On the current most popular 64-slice devices, much lower radiation exposure is possible, on the order of 0.8-1.2 mSv routinely--if the center takes the effort.

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