Map of life expectancy at birth from Global Education Project.

Thursday, November 30, 2006

Insanity masquerading as dissent

Today's NEJM has the results of a much anticipated study on HIV treatment. (Abstract only, but that's all you want anyway.) Because the antiretroviral drugs used to control HIV can have serious side effects, there has long been interest in the idea of "episodic treatment."

As I assume most readers know, the most important disease process caused by HIV infection is destruction of certain cells of the immune system, called helper T-cells, which display a receptor protein called CD4. The CD4 receptor is the route by which HIV enters the cell. Then it takes over the cells genetic machinery and causes the cell to devote itself to making copies of HIV. Eventually the cell dies. However, the body keeps making more CD4+ cells. Eventually, however, for reasons that are not entirely clear, the production of new CD4+ cells cannot keep up with their depletion by HIV, and the result is the immune deficiency syndrome known as AIDS.

Antiretroviral drugs interrupt the cellular processes by which HIV is replicated. Hence they can prevent the progression to AIDS. But they can also have serious side effects, and so many doctors and patients hoped that they could be used sparingly. Specifically, the idea was to initiate treatment only when the CD4+ count fell below a certain level, and then to stop it when the count rose above some threshold. This study used 250 cells per milliliter of blood as the threshold for initiation of therapy, and 350 as the threshold for suspending it. Unfortunately, it didn't work. The patients using the "drug conservation" strategy got sicker faster, and were more likely to die. We're back to the conventional wisdom: the best thing to do is to treat HIV disease continuously and scrupulously, trying not to miss any doses of the medications and not interrupting treatment. The side effects are unfortunate, but risking them is better than not suppressing HIV replication.

The reason for the headline on this post, and the reason I thought this rather specialized subject was worthy of a post here in the first place, is that this study is yet one more of the innumberable overwhelming and irrefutable proofs that yes, infection by Human Immunodeficiency Virus is the cause of AIDS, the virus causes AIDS by destroying CD4+ cells, and antiretroviral drugs control viral replication and thereby control the disease. In the present study, there was a close relationship between drug treatment and CD4+ levels, and between CD4+ levels and illness and death. End of story.

And yet for some not fully explicable reason, there continues to be a movement, of people who view themselves as somehow being progressive or liberating, who deny these incontrovertible facts. I am a long-time subscriber to Harper's Magazine, which I generally like very much, but in March of this year Harper's disgraced itself and did long term damage to its reputation by publishing an article by one Celia Farber dedicated to denying that HIV causes AIDS, and to the proposition that antiretroviral drugs are in fact the principal cause of the disease. The theory that HIV causes disease was attributed to a conspiracy among scientists lapping up research grants, and drug companies peddling poison. The editors have refused to isue any retraction or to apologize for their astonishing lapse in judgment.

The community of AIDS deniers has done its greatest damage by somehow capturing the heart and mind of the president of South Africa, Thabo Mbeki, who for many years resisted implementing widespread treatment for HIV in that disastrously afflicted country. Now, it's too bad that HIV causes AIDS and that the only available treatments are expensive drugs with serious side effects that don't cure the disease and so need to be taken for the rest of one's natural life. That does indeed mean big profits for drug companies, the need for ongoing expensive research, tough luck for people with HIV, and even tougher luck for people with HIV in poor countries. I very much wish it weren't true. But there you are.

People who want to know the truth about Farber's tissue of lies can read the refutation from leading HIV specialists here. (It is likely, by the way, that first author Robert Gallo took undeserved credit for discovery of HIV, which properly belongs to the French investigator Luc Montagnier. That is not logically related to the question of whether HIV causes AIDS.) If you want all the straight dope, it's here, at the web site of AIDS Truth.

People often try to position themselves as courageous crusaders and progressive revolutionaries by denying what the "establishment" of experts contends to be the truth. (Viz. the despicable Robert Kennedy Jr. and his dishonest, defamatory and deeply dangerous campaign to promote the utter falsehood that vaccination is the cause of autism.) But the progressive revolutionary position in this case consists of advocating for justice for all people infected by or at risk for HIV, including universal access to antiretroviral treatment. That's reality based radicalism.

Blog pimping: Dr. Rick is once again blogging away on Critical Condition. And I have a new post up on the Dialogue. Do check them out if you are interested. (And I can't really have a dialogue without you.)