Tobacco On Trial

On Redirect, Eubanks started with the SIDS material, establishing that Monograph 13 and the IARC study found maternal smoking causes SIDS.

Judge Kessler asked, “ETS causes SIDS?”

Samet here again showed his habitual exactitude: ” I have been careful to say _maternal_ smoking causes SIDS. Mothers often continue to smoke after birth, and there is some evidence that family smoking may contribute to SIDS. But _maternal_ smoking causes SIDS.”

Eubanks then asked about the lung cancer benefits of light cigarettes found in IARC and MONO 13. Samet said the studies had found no benefits for COPD and chronic heart disease (CHD)–the causes of huge numbers of deaths.

Wednesday, Samet had been asked by Bob McDermott (Jones Day/RJR) if diet were a potential confounder in ETS/lung cancer studies. Samet had said no. McDermott had then introduced a 1995 paper (”Characteristics of nonsmoking women in NHANES I and NHANES I epidemiologic follow-up study with exposure to spouses who smoke.” Am J Epidemiol 1995; 142: 149-57 ) suggesting just that. AND it was written by a fellow researcher at Johns Hopkins, Genevieve Matanowski. Samet had seemed surprised, knew Matanowski fairly well, and expressed utmost respect for her work.

Eubanks now displayed the first page of the Matanowski study in question, and asked Samet to read the bottom lines: they acknowledged funding from CIAR. Eubanks then produced a CIAR document that talked about “minor comments” on, among other items, the Matanowski study. The comments, the paper read, had been accepted.

Then discussion turned to the notorious 2003 BMJ Enstrom/Kabat study.

Eubanks asked Samet what were the concerns of the Public Health community about the study. Samet said it had serious limitations, and it added little to the literature.

Then she asked about the Richard Smith BMJ Rapid Response from 5/18/03, which Bob McDermott had cited:

“We are certainly interested in the question of whether passive soming (sic) kills, and it’s clear to us that the question has not been definitively answered. Indeed, it may well never be answered definitively. It’s a hard question, and our methods are inadequate.”

(I believe McDermott in his cross had referred to this piece as an “editorial.” He definitely mentioned there was an editorial in the same issue as the Enstrom/Kabat piece–and there was, but it was by a George Davey Smith, not Richard. I don’t believe McDermott quoted from the Davey Smith editorial. I hate to be a stickler, but I know McDermott certainly never used the term “Rapid Response.”)

Eubanks then introduced the Hackshaw, et. al. letter. It was signed by the Working Group that reviewed the evidence on involuntary smoking and cancer for the IARC study–a group that included Samet himself, as well as Sir Richard Doll. The letter to the BMJ read,

[The IARC report, based on the full scope of the scientific evidence, including observational studies, concluded that exposure to environmental tobacco smoke (ETS) is a cause of lung cancer. The recent paper by Enstrom and Kabat, does not diminish that conclusion, nor the similar conclusions of many previous reports. . . .

The classification of ETS as a human carcinogen by IARC was not based on the epidemiological evidence alone. The IARC monograph sets out in detail the carcinogenic components of ETS, the effects of ETS in experimental models, biomarker studies, and the observational studies. Additionally, active smoking has long been established as a cause of lung cancer and knowledge of mechanisms of carcinogenesis implies that there is no risk-free level of exposure to tobacco smoke. Enstrom and Kabat’s conclusions are not warranted by the weak evidence offered in their paper and the accompanying editorial alludes to “debate” and “controversy” on ETS and lung cancer that we judge to be resolved scientifically, even though cynically continued by the tobacco industry.

Samet affirmed that, “Enstrom and Kabat’s conclusions are not supported by the weak evidence they offer.”

Eubanks then introduced a glowing assessment of Samet that was made in a Shook Hardy(!) document. Eubanks highlighted, “Samet carefully assess available information prior to drawing general conclusions.” (Anyone who had listened to Samet’s answers under both cross examination and redirect would most emphatically agree.)

Eubanks finally asked what had happened between 1984 and 1986 to change Samet’s opinion that secondhand smoke causes lung cancer.

Samet said, “Science is not static. New studies came along, including the (1986) Surgeon General’s review of the entire scope of evidence. My 1984 article was dwarfed by the Surgeon General’s review.”

This entry was posted on Saturday, October 2nd, 2004 at 10:16 pm and is filed under Notes. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.