The Nation's Health + [life]

Deja vu all over again?

HeartHawk brought a report and debate on The Heart.Org website to my attention:

Screening for risk factors or detecting disease? Debate divides the CV community. After landing on theheart.org, paste this onto your URL address:article/883239.do. (Full address: http://www.theheart.org/article/883239.do. I don't know why, but I couldn't go there directly.)

Some interesting comments:

Dr. Jay Cohn (University of Minnesota):

"They're saying that we can't identify disease very effectively so let's just stick with risk factors, which we know are very poorly predictive and nonspecific. It boggles my mind as to why they won't open up their minds to the importance of moving forward in finding better strategies to identify the disease that we are treating. It's very strange. They criticize these disease markers because they are not predictive of events, but they are looking at very short-term outcomes. We're interested in lifetime risk. We're screening people in their 40s who are concerned about morbid events in their 60s and 70s, and no trials are going to track them that long."

"You have to accept the pathophysiologic reality that heart attacks don't occur in the absence of coronary disease, and coronary disease doesn't occur in the absence of endothelial dysfunction and vascular disease, all of which now can be identified."

". . . Can we as a society and as a profession accept the idea that there is a link between the vascular abnormalities and the events? "And that that linkage is tight enough that it should allow us to accept slowing of progression of the vascular abnormalities as an adequate marker for slowing disease progression, without waiting for events to occur? As soon as you use the word surrogate, people jump up and say we have all these markers that we know don't work well—things like premature ventricular contractions [PVCs] on the electrocardiogram, LDL, HDL—but those are not the markers we're talking about. We're talking about structural and functional changes in the blood vessel and in the heart."

Wow. The idea may be starting to catch on.

As an interesting aside, Cohn et al use a 10-test panel to screen for vascular disease:

"Named for the center's benefactor, the Rasmussen score includes tests for large and small artery elasticity (compliance), resting blood pressure, blood-pressure response to moderate treadmill exercise, optic fundus photography, carotid intimal-media thickness (IMT), microalbuminuria, electrocardiography, left ventricular (LV) ultrasonography for LV volume and mass, and brain natriuretic peptide (BNP). Each test result is scored out of 10 for low, intermediate, or high risk, and the combined results yields a score that Cohn et al believe is more predictive than any of the existing standalone tests."

The counterarguments in this debate were provided by Dr. Philip Greenland (Northwestern University), who repeated his oft-used argument that, while he accepts that vascular disease can be identified, no one has proven that measuring it improves outcomes:

"We do have that evidence for risk-factor screening. Even though people criticize risk-factor assessment because it is not sensitive enough or not accurate enough, the interesting and curious thing is that we actually have evidence that if you go to the trouble of screening for risk factors and treating them, patients have better outcomes. We do not have that evidence for any of these other tests."

An interesting debate ensues that includes Track Your Plaque friend, Dr. William Blanchet, who characteristically argues persuasively in favor of broad screening for coronary disease with coronary calcium scoring:

"If we were doing our jobs in primary prevention, we would not need to look at improved intervention and secondary prevention to reduce coronary death."

Here's a shock: Dr. Melissa Shirley-Walton, the cardiologist who previously preached the "cath lab on every corner" argument seems to have undergone a change of heart:

"What if I walked up to a gentleman and said, "you are at risk for CAD, take a statin", to which he replies, "I'm afraid of those meds". BUT if he sees his calcium score........he is then convinced to be pro-active. What is so wrong with that? What is so wrong with allowing him to spend 250.00 US out of pocket in order to save the US 150,000.00 US later on?

No hard endpoints you say with intensive therapy for primary prevention? What about extrapolating from trials for secondary prevention like HATS? ARBITER2? And what exactly is the true definition of secondary prevention? Is it truly primary prevention if we already have intima thickness abnormalities, or fatty streaks? That would more likely fall under secondary prevention by today's new standards.

So, I'm all for any visual aid that will encourage compliance with life style change, necessary medical therapy and followup. If the patient is willing to spend 250.00$ to get a calcium score, so be it. Better yet, why not lower the price so everyone can have the option if they are motivated enough to seize an opportunity?"

I have to admit that I thought that Dr. Blanchet was wasting his time trying to persuade Shirley-Walton et al, but perhaps he is having an impact, though having hammered away at them for the last year or so.

These arguments, for me, eerily echo many previous debates I've heard. But I am encouraged by the more favorable treatment the notion of atherosclerosis screening is receiving. Just 5 years ago, all coronary calcium scoring would have received from the conventionalists is "more clinical studies are needed."

So perhaps the cardiology and medical worlds are inching slowly towards broad acceptance of screening for coronary and vascular disease.

BUT, screening is not sufficient. What do you do with the information?

Here is where the conventional-thinkers stop. The question that seems to occupy them: Perhaps we should screen people for hidden coronary and vascular atherosclerosis so we can better decide who needs a statin drug or a procedure.

I would pose a different challenge: We should screen people for hidden coronary and vascular atherosclerosis so we can better decide who needs to engage in an intensive program of disease reversal using natural means and as little medication and procedures as possible.

Well, perhaps in time.