« July 2007 | Main | September 2007 »
August 28, 2007
On Circulation and Truth
Why is it that for nearly 1300 years intelligent doctors and philosophers followed Galen's very bizarre misunderstanding of the function of the heart and the blood. Why did everyone believe Galen (and his view was an improvement over the previous five hundred years)?
People had obviously looked at hearts from the time of Moses at least, and probably from Abel. But Galen decided from his otherwise very careful observations (this was a fellow who could do cataract surgery among others) that the venous and arterial systems were unconnected, that the spirit principle entered the lung and thus the blood and somehow diffused through pores in the septum of the heart to join the vital principle coming from the liver, which generated the blood for the rest of the body, where it was consumed. There is evidence that Galen even recognized the pump function of the heart. (The heart valves were discovered by Erasistratus around 300 years before Christ, or nearly 500 years before Galen. Galen knows there is evidence for a one way flow, and he knows these arguments for the pump feature. He corrects the very mistaken notion that the vessels are full of air.)
His inability to see the capillaries should not have prevented him from making the simple calculation that Harvey later made of the untenable quantity of blood consumed each day under his theory.
It has been argued that Galen's desire to vindicate Plato's view of the soul against the Stoics blinded him to the obvious conclusions of his observations.
What explains the ensuing 1300 years of willful blindness? (There might have been a Muslim, Ibn Al-Nafis, who discovered the pulmonary circulation a few hundred years prior to Harvey, being uninhibited by the Greek philosophical arguments.) There was certainly there was much distraction from investigation. The prohibitions against dissection existed in Rome as well as in the church, so it wasn't just that, though the prohibition may have meant more to Christians for different reasons. (Vivisection of animals was at least discouraged by the church, if not fully prohibited at times. This was a important part of Harvey's experiments.) Basically, I think there was no incentive theologically to change the view.
It has been argued that lack of accurate experimentation is what kept first Erasistratus, then Galen, then Spieghel, from drawing accurate conclusions. Granted that these men did not have all the tools, or all the colleagues competing, or all the previous knowledge and successes to build on. Nonetheless, they were incredible observers, great theorists, insightful concluders. Except when their assumptions were wrong.
So what looks like the accurate scientific explanation might not be,
even if it held for 1400 years. And wrong interpretations flow from
wrong presuppositions, theological ones.
Posted by Robert Maddox at 03:33 PM | Comments (0)
August 23, 2007
Sick review
Yes, I read the book by Jonathan Cohn, a journalist. He writes with a journalist's instincts and style (whatever that means). It is an engaging book, leading the reader from one tragedy to another. Each chapter focuses on a person in a different geographic location with a different aspect of the socio-political problems in health care delivery.
Along the way, he gives some interesting history about insurance, various hospital systems and political maneuvering.
The Committee on the Costs of Medical Care met in 1926 and issued a report in 1932, concluding that the proportion of national resources for medicine must increase. This was immediately prior to FDR and the New Deal. And states had already begun to pass pension laws. But the foundation was laid. The author attempts to show that several opportunities for a single-payer system were missed.
After the heart-wrenching stories interspersed with historical and political vignettes and arguments, he finally asserts that the problem is ambivalence of public opinion, since most people have adequate health care and payment options. He further asserts that the problem cannot be solved by the private sector. Bush and many conservatives are confused by HSAs because they wrongly believe that “the fundamental problem with American health care today is that people have too much insurance.” P.221 He admits that this has some basis, but the HSAs solution focuses on the patient to the exclusion of the providers. Then the kicker: “How are consumers supposed to shop for good medical care when most experts still don’t agree on how to measure it?” Yet the proposal is a system in which the government decides what is good and the private sector provides it in cooperation. So what he proposes is a universal health care system, based on the French model, “quasi-independent sickness funds, which are overseen by the government."
He claims that in contrast to the “moderate conservative” principles which are short on comfort or hope, his “vision of universal health care—one traditionally articulated by liberals—offers optimism. To believe in universal health care is to believe that we can do more and do better, all at once—that it is possible to have hospitals full of high technology and emergency departments with room for all comers; that it is possible for people to choose their doctors and have a say in their treatments; that it is possible to make the economy more free and more efficient; and that it is possible to do all this for everybody, not just an economically or medically privileged few, in a way we can all find affordable.”
In a universal health system, maybe all the people he highlights that suffered under the current system might not have suffered or died, and the world would be a perfect place. But none of their problems could really be prevented, fixed, or definitively managed well by modern medicine. Each has components of individual responsibility and other social factors.
“To its critics on the political right, universal health care is an imposition on liberty that weakens individual initiative. But this is the classic bait-and-switch of modern conservatism—to make us forget that in a democracy, the government is merely an expression of our will and resources as a community. Universal health care is really about finding collective strength in our individual vulnerabilities." Is this not also a bait-and-switch? Isn’t finding collective strength in our individual vulnerabilities what Babel was all about? And God frustrated that plan, until the Rock cut without hands was come.
Posted by Robert Maddox at 08:16 PM | Comments (0)
August 07, 2007
Pulmonary Embolism
A blood clot to the lung will kill you. Well, maybe 10% of the time. ACEP (American College of Emergency Physicians) and others are back on the push not to miss any. And that is a good push, since many lawsuits arise out of this very failure to diagnose. But many of the deaths from a PE are within one hour, and probably couldn't be prevented.
So we are told we miss 400,000 of these a year. Only 100,000 of these are preventable by quick diagnosis and treatment. (Presumably this is mostly the 30% who die with a recurrent clot.)
The symptoms for a PE are frequently misleading and vague. There is no perfect test for a PE. Some are better at ruling against, some better at ruling for, but none are good at both. So we are to test the tens of millions of people who present to an ER with these vague symptoms, in the hopes of finding the 400,000 we are missing, and in the hopes that the treatment for these will prevent 100,000 deaths a year.
And at what cost? At what danger to the tens of millions unnecessarily subjecting to sometimes invasive, frequently expensive, and always worrying testing? What of those unnecessarily put on blood thinners, who then develop complications or death from bleeding?
And what of the unnecessary and unproven surgery that put these people at risk in the first place, or the car wreck that put them at this further risk, or the oral contraceptive they shouldn't be using?
Did they die of a PE, or at the hands of a surgeon, or bad driver, or immoral behavior?
Posted by Robert Maddox at 05:02 PM | Comments (0)
Gardasil's safety
The CDC released the first year's safety data for Gardasil (recall that that was the first of the HPV vaccines). More than 5 million doses have been distributed (as of March), though it is not clear how many have been administered). The overall vaccine adverse event reporting rate is 33/100,000, with a serious adverse event rate of 1.8/100,000.
These are very reasonable numbers, if the vaccine were reasonable. Of the nearly 1800 events, most were mild (vomiting, passing out, fever, headache, dizziness). Only 13 were the very serious Guillain-Barre Syndrome. (13 cases of GBS would be enough to shut down any other vaccination program this early in the course.)
And only four people have died. Now, a link to the vaccine hasn't been proven. And women die all the time in this age group (9-26). Why is one in million deaths from the vaccine (ok the link isn't proven) acceptable but one in a million deaths from cervical cancer (preventable by obedient chastity) not acceptable? To prevent one in a million deaths, we cause one in a million?
Posted by Robert Maddox at 04:32 PM | Comments (0)
HPV Vaccine efficacy
Though nothing more needs to be said about the misguided effort pushing the HPV vaccine, I am in need of pushing the point.
GSK's new vaccine (only bivalent-two strains of HPV) received great support from a study published in Lancet. The study, designated PATRICIA (the Papilloma Trial to Prevent Cervical Cancer in Young Adults), was led by Dr. Paavonen, and others who are employees or on the payroll of the manufacturer. But don't get sidetracked by the improprieties.
Over 18,600 women, ages 15-25, from 14 countries, were studied for 15 months. Of those who received the vaccine, only 2 (of the 9,319) developed high-grade CIN associated with type 16 or 18. Of the other 9,325 women not given the vaccine 21 developed these high-grade lesions. So the vaccine is touted to have a 90% efficacy.
Note that it has not prevented cancer (that won't show up for a decade). Note that the enrollment criteria (who they let in the study) were tight, so this is not a generally applicable study. And note the high rate of side effects, which included joint and muscle aches as well as local effects.
But don't lose sight of the bigger context. This is a sexually transmitted disease. It only kills at lightning strike rates. And finding even "high-grade lesions" can lead to unnecessary procedures, worry, time and financial waste, and even further harm, with the high false positive rate.
Posted by Robert Maddox at 04:17 PM | Comments (0)
August 03, 2007
Restless Leg Syndrome
It is official. Since genomic variations have been found in half of people with RLS, it is now officially a condition, otherwise known as a disease. Not that any more can be done about the admittedly irritating symptom just because it is official.
It is telling that though the prevalence is estimated at somewhere between 3-10
% of the American population, the genetic variation is present in perhaps 65% of the American population, and about half of people with the Syndrome do not have this genetic variation.
What is wrong with this picture? Does anyone seriously think that genomic medicine is the answer to our suffering?
Posted by Robert Maddox at 01:06 AM | Comments (0)
August 01, 2007
more on deCODE
On rereading the article I can't link, I am infuriated and bemused. I have no doubt that much money will be transferred (not made) for foolishness like this. The study in question found 50 genetic differences between high-risk cardiac patients and healthy, older people. But when these were run against other similar studies, only two were found consistent. (Remember the Non-validation study by Morgan etal.) So at least they had the honesty to check their work against other studies. But any of the 50 could have a claim. Just because these two check out so far, what makes us think there is an actual causal relationship? This is not even a reasonable gene that is being discussed.
Further, nearly 1/4 (25%) of the normal healthy participants have this same variation. The variation is only found in 33% of the high-risk group. This is notably a 33% increase, meaningless when seen in absolute terms of 8% difference. But the meaninglessness transmogrifies into a beastly and hurtful significance if such genetic testing takes hold. What happens to the 25% of the healthy population who, GATTACA-style, are deemed defective on the basis of this variant? What happened to Uma. She makes herself a cardiac cripple on the basis of the test. And this is the Nemesis.
Posted by Robert Maddox at 11:45 AM | Comments (0)
genomic heart risk
A commentary on "The Genomics Gold Rush" in JAMA 298, 2 (July 11) sent me looking for more about the author. Topol is a leading cardiologist who has been recruited to head up a translational genomics program at Scripps in La Jolla. He gives a helpful overview of the magnitude of the problem that researchers in this field face. In 2001, when the human genome sequence was published, it was predicted that in just a few years, we would start seeing cures based on genomics. Topol walks us through why that has not happened, though he obviously still thinks it will, since there have been several more breakthroughs. But the statistical and financial challenges are still staggering. (And for the record, I don't believe for a moment that he sees the proper end. Recall the quest for the ultimate subatomic particle. This is just the beginning of many centuries of the renewed search for the secret of life. Ask any alchemist.)
But that has not stopped the GATTACA project. There will be billions to be made in the gene detection business before it is realized how useless it is, even counterproductive. Note in this article (that I can't seem to link but was from Heartwire May 3 2007 about a Danish study and Ottawa study and subsequent marker kits) that even though there is no proven utility to this knowledge, marketing is fool speed ahead. It is ironic that the commentaries following Topol's in the JAMA mentioned are "The Relevance of Cost-effectiveness Analysis to Clinicians and Policy Makers" and "Meeting the Survival Needs of the World's Least Healthy People." I can hear God laughing at our hubris.
Posted by Robert Maddox at 11:05 AM | Comments (0)