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Warning: the health police can
seriously addle your brain
By Robert
Matthews
(Filed: 18/05/2003)
It was a rare good news story in an otherwise grim
week. A landmark study into the effects of inhaling other people's
smoke revealed that fears that passive smoking kills more than 1,000
a year in the UK alone are unfounded.
After studying the health of tens of thousands of
people married to smokers, US researchers found that they face no
significant extra risk of lung cancer or heart disease. It may sting
your eyes, take your breath away and make your clothes smell, but other people's cigarette smoke will not kill you.
The demise of a supposed major risk to public health
might be expected to prompt celebration among medical experts and
campaigners. Instead, they scrambled to condemn the study, its
authors, its conclusions, and the journal that published them. The
reaction came as no surprise to those who have tried to uncover the
facts about passive smoking. More than any other health debate, the
question of whether smokers kill others as well as themselves is
engulfed in a smog of political correctness and dubious science.
Researchers who dissent from the party line face
character assassination and the termination of grants. Those who
report their findings are vilified as lackeys of the tobacco
industry, and accused of professional misconduct (in 1998,
campaigners tried to have this newspaper censured by the Press
Complaints Commission for our reports on passive smoking. They failed.).
The furore over last week's negative findings,
reported in the respected British Medical Journal, has its origins
in research published in the same journal in October 1997. After
reviewing the evidence from dozens of studies, researchers at the
Wolfson Institute of Preventive Medicine, London, concluded that
being married to a smoker increases the "risk" of lung cancer and
heart disease by around 25 per cent.
The results were seized on by health campaigners as
final proof of what they had known all along: that smokers are not
just killing themselves - they are also killing innocent bystanders,
and must be stopped. The same issue of the BMJ carried an editorial
by Dr Ronald Davis, the editor of the journal Tobacco Control,
declaring: "Health advocates should pursue all strategies that would
help accomplish that goal, including education, legislation,
regulation and litigation."
Just how willing campaigners are to pursue all
strategies soon became clear. In March 1998, The Telegraph revealed
that an international study by the World Health Organisation had
failed to find any convincing evidence of a link between passive
smoking and cancer. The article prompted uproar among anti-smoking
campaigners and denials from the WHO, which insisted that the study
had found a 16 per cent increase in cancer "risk" among those
married to smokers.
The WHO, in what has become a standard ruse in the
passive smoking debate, ignored the fact that the 16 per cent risk
figure was not "statistically significant". That is, it had failed
to meet the standard of proof usually demanded by scientists.
As The Telegraph has discovered, however, passive
smoking research is an area where the usual standards do not apply.
If they did, last week's wholly negative findings would have
surprised no one. For long before the publication of the original
BMJ studies, it had been clear that the 25 per cent extra risk
figure was likely to prove a wild exaggeration.
The evidence comes from research into a key issue in
the passive smoking debate: just how much smoke do non-smokers
actually inhale? Surprisingly few attempts have been made to gauge
smoke exposure directly. Those that have raise grave doubts over
claims that passive smoking poses a significant health risk.
In studies across Europe over the past decade, air
quality experts at Covance Laboratories, Harrogate, gave air
monitors to thousands of people and measured their exposure to
smoke. The startling results showed that passive smokers are exposed
to the equivalent of six cigarettes a year, an extra lung cancer
risk of 2 per cent compared with non-smokers. The figure is 10 times
lower than the BMJ studies claimed.
So small a risk is, however, in line with last week's
negative findings. It also explains an awkward fact rarely mentioned
by anti-smoking campaigners: more than 80 per cent of all studies of
passive smoking have failed to find a statistically significant link
to lung cancer. Only by subjecting them to abstruse statistical
techniques can they deliver the goods.
One technique is anything but abstruse, however. It
involves simply ignoring results that do not fit. In the original
BMJ reports, a major US study showing no extra heart disease risk
from passive smoking was excluded on the grounds that it did not fit
with the positive results, and had been funded by the tobacco
industry. The air monitoring studies have been ignored for the same
reasons.
Scientists are understandably chary of research
backed by an industry with a history of deceit. Yet so widespread is
the conviction that passive smoking is a proven killer that
researchers who think otherwise have little choice but to apply for
tobacco industry support. Prof James Enstrom, of the University of
California, the lead author of the study whose negative findings
sparked last week's controversy, said the research would never have
seen the light of day, except for support from the tobacco
industry.
Originally set up in 1959 by the American Cancer
Society, who recruited 118,000 Californian adults into the study,
the follow-up effort was long supported by taxes levied on
cigarettes. In 1997 the funding was suddenly cut off. Prof Enstrom
suspects that health officials in California just were not keen to
fund research that might undermine the original BMJ studies.
Prof Enstrom, compelled to take tobacco industry
money to complete the study, then found that journals were unwilling
to publish his negative findings. He told The Telegraph: "One
journal we tried had published three positive studies before, but
despite getting a glowing referee's report on our work, they refused
to accept it."
After the BMJ published it last week, he has been
subjected to a barrage of criticism: "The whole process has been
aggressive, vitriolic hate," he says.
Within hours of publication, he and his co-author Dr
Geoffrey Kabat, of the State University of New York, came under
attack by the very organisation that had set up his study: the
American Cancer Society. "We are appalled that the tobacco industry
has succeeded in giving visibility to a study with so many
problems," said a spokesman, adding that the study was "neither
reliable nor independent".
But, Prof Enstrom said, the speed of the society's
response to the negative findings is particularly revealing. "They
wrote the complaint before they even saw the paper," he said.
In the UK, the anti-smoking pressure group Ash
accused Prof Enstrom and his colleague of "deliberately downplaying
the findings to suit their tobacco paymasters". But Prof Enstrom
says they were subjected to rigorous peer review, and denies tobacco
industry influence.
The denial appears to have satisfied the BMJ. Dr
Richard Smith, the journal's editor, told The Telegraph that the
decision to publish the findings was made only after they had been
thoroughly refereed, and full disclosure made of the source of
funding. "This is a big study with very complete follow-up about an
important question," Dr Smith said. "I take the view that not to
publish is a form of scientific misconduct."
Now Dr Smith, too, is under fire from his own
colleagues. Dr Vivienne Nathanson, the head of science and ethics at
the British Medical Association, said: "There is decades of
overwhelming evidence that passive smoking causes lung cancer and
heart disease, as well as triggering asthma attacks."
The reference to asthma hints at a new strategy by
anti-smoking campaigners - towards a focus on the health of
children. Unlike the risks from lung cancer and heart disease, the
evidence that passive smoking damages the lungs of children is
strong. Last week the British Thoracic Society called for more
funding into this aspect of the smoking and health debate. That
suggests that children with disorders such as asthma may soon become
the focus of attempts to introduce a total ban on smoking in public
places.
In the meantime, health campaigners show no
enthusiasm for giving up their most potent claim: that the person
puffing away next to you is not merely making your eyes water, but
killing you as well. The scientific evidence is just not there, says
Prof Enstrom. "But maybe we've gone past the point where anyone
cares about the facts."
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