We've all heard the catch phrase "studies have shown" as an assurance that there is hard evidence to back up a claim. Usually the people trying to convince us of their assertions with those three words have read nothing but the thumbnail conclusions in the abstracts of those studies. Here Dr. Rasnick shows how some HIV researchers employ the logic Alice encountered through the looking glass to come to their conclusions. Even though more than twice as many HIV positive babies soon became sick after birth to AZT treated HIV positive mothers as compared to HIV positive babies of non-medicated mothers, the researchers came up with some twisted rationale to conclude that AZT was beneficial. From David Rasnick: Here is the latest in a recent series of reports on the lack of clinical benefits of AZT treatment of HIV positive children. Ricardo S. de Souza et al., (2000) Effect of prenatal zidovudine on disease progression in perinatally HIV-1-infected infants, Journal of Acquired Immune Deficiency Syndromes 24: 154-161. [Full Text]Anyone trying to explain the HIV insanity to others should get this paper; make photocopies and give them to people to read. This paper sums up what we're up against-the diseased minds of those working on HIV. If the person you are talking to doesn't see the insane thinking of the authors of this paper, then don't waste your time presenting them with evidence. In spite of the fact that this is a very poorly executed study in that it did not include HIV negative infants born to HIV positive mothers treated with AZT during pregnancy as a control group and that the so-called rapid progression of disease (RPD) category used by the authors lumped together deaths and AIDS defining diseases and conditions, the toxic and lethal effects of AZT come screaming through, nevertheless. For example: "After adjusting for prematurity and maternal clinical characteristics, RPD was three times more likely to occur in infants born to [AZT] treated compared with findings in [AZT] untreated mothers." In fact, Figure 1 of the paper clearly shows a dose response curve. The earlier the mother began AZT treatment while pregnant, the sooner her HIV positive child got sick and died compared with the HIV positive children born to HIV positive mothers who did not take AZT during pregnancy. That's the data. Now did the authors make the obvious observation that AZT treatment during pregnancy may be harmful to the newborns? Of course not. Here is the somewhat hopeful-sounding first two sentences from the discussion. "Our results suggest that maternal treatment with [AZT] may influence the course of disease among perinatally infected infants. In this retrospective study, the risk of RPD was five to six times higher among infants born to [AZT] treated compared with [AZT] untreated mothers." But the give away to the diseased thinking of the authors is the phrase "may influence the course of disease". In other words, rapid disease progression (RPD) is not due to AZT but to the wily HIV. I could not find any mention of the toxicity of AZT in the paper. Instead, the authors make the convoluted argument that AZT was actually beneficial in that if reduced the transmission of HIV from mother to child. In order to make their case, the authors rely on two hypothetical modes of transmitting HIV to the infant: intrapartum and intrauterine. They speculate that, "If [AZT] is "primarily effective in preventing intrapartum transmission and if NRPD [nonrapid disease progression] develops as a result of this mode of transmission (while RPD develops as a result of intrauterine transmission), then [AZT] should preferentially decrease the proportion of infected infants with NRPD." Lewis Carroll would have applauded the audacity of this intellectual slight of hand on the part of the authors. The authors transformed the obvious results of their data, that AZT treatment of pregnant women in a dose dependent manner increases the number of sick and dead infants (RPD in the authors words) into the conclusion that AZT decreases the proportion of HIV infected infants who aren't sick or dead (NRPD nonrapid disease progression). From this bizarre twisting of the evidence, the authors end with this: "The clinical ramifications of our findings are twofold. First, if [AZT] monotherapy preferentially decreases intrapartum transmission without affecting intrauterine transmission, then more effective regimens that can prevent intrauterine transmission need to be developed. Second, because of the increased risk of RPD, highly active antiretroviral therapy should definitely begin at an early age for any perinatally infected infant born to a treated mother." In other word, give the poor mothers and infants even more drugs. NOTE: Dr Rasnick makes a very import point that I would like to expand on. The study did not include HIV negative infants born to HIV positive mothers treated with AZT during pregnancy as a control group. In their conclusions the author's speculate: The rate of RPD [rapid disease progression] was significantly higher among perinatally infected infants born to HIV-infected mothers treated with ZDV than among infected infants born to untreated mothers. The decreased proportion of infected infants with nonrapid disease progression in the former group might be related to the ability of ZDV to block intrapartum transmission preferentially and also to nonrapid disease progression resulting from intrapartum transmission.If the study had included the much larger group of babies born HIV negative to both mothers on and off AZT this speculation could have been tested. With HIV out of the scene as a possible villain, how well did HIV negative babies do after being born to AZT treated mothers?? The exclusion of the HIV negative control group is a prime example of how HIV researchers set out to ignore data that might be hostile to their pet hypothesis. Robert Johnston How to Read a Paper By Trisha Greenhalgh British Medical Journal This is a series of articles introducing non-experts to finding medical articles and assessing their value. The author reminds us "that some (perhaps most) published articles belong in the bin, and should certainly not be used to inform practice." Ms. Greenhalgh is highly critical of drug company "reps" or "detailers"; she offers helpful advice for deconstructing drug company hype. These articles also function as a glossary of terminology (surrogate markers; accuracy, specificity, sensitivity and predictive values of tests; etc) with clear explanations and examples. Sections 6 & 7 are highly recommended: Papers that report drug trials Papers that report diagnostic or screening tests  TORONTO
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