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Historical Keynote
Addresses
Richard Doll Gives
Honorary Lecture on the History of Tobacco at New York Academy of
Medicine
In what the New York Academy of
Medicine described as “a rare appearance in the United States,”
British epidemiologist Richard Doll delivered the
Sylvia and Herbert Berger Lecture in late April on the medical history
of tobacco. As one of the principal authors in the famous Doll and
Hill report of 1950 helping to establish the relationship between
tobacco and lung cancer, Doll was able to offer a unique perspective
on the history of how epidemiological evidence accumulated to
establish causation.
Below are some of the key facts
and perspectives found in Doll’s historical review:
• Five case-control studies
published in 1950, particularly the Wynder and Graham and the Doll and
Hill studies, helped to radically change how people viewed tobacco and
lung cancer. The two studies stood out because of their size; the
precision with which lifelong non-smokers were defined; and the
argument that led to their conclusion.
• Cohort studies were judged
necessary because most accepted that an association had been shown but
not that it implied cause and effect. Consequently, the now famous
Doll and Hill cohort study of British medical doctors and the large
Hammond and Horn study in the US were carried out and reported in
1954.
• The detailed evidence that led
to the claim that cigarette smoking was an important cause of lung
cancer was the extraordinary strength of the association (20 fold risk
in heavy smokers), the diminution of risk with cessation of smoking,
and the consistency of findings in different studies across
populations.
• Following the reports by the
Royal College of Physicians in London in 1962 and the Advisory
Committee of the US Surgeon General in 1964, the idea that smoking was
a major cause of lung cancer ceased to be seriously challenged.
• Since the 1960’s, cigarette
smoking has been found to be positively associated with 50 causes of
death or morbidity and to be negatively associated with eight or nine.
Some associations are due to confounding, but the great majority arise
because tobacco smoke is a contributory cause.
• In retrospect, strong
resistance to the idea that smoking caused so much disease was due to
the ubiquity of the habit, the novelty of the epidemiological
techniques, and the primacy given to Koch’s postulates (the evidence
from non-smokers with lung cancer was taken to prove that smoking
could not be THE cause and the possibility that it might be A cause
was inappropriately doubted).
Published May 1999
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