At the American Medical Association's annual meeting in Chicago last
week, when the doctors got around to discussing medicine instead of
medicare, topic A was the danger of smoking. Physicians already
familiar with tobacco's implication in the growing incidence of lung
cancer were startled to hear that they had been worrying about one of
the least of tobacco-caused troubles. Lung cancer brought on by
cigarette smoking, reported the American Cancer Society's chief
research statistician. Dr. Edward Cuyler Hammond, is “relatively
unimportant'' compared with the damage tobacco does in a variety of
other ways. Focusing popular attention on the 30,000 deaths from lung cancer each
year, said Dr. Hammond, has obscured the more deadly fact that four
times as many “excess'' fatalities among cigarette addicts are due
to a long and tangled chain of events. Between puffs on his pipe, he
reported that deeply inhaled cigarette smoke sends a threat of pre
mature death spreading through the lungs, arteries and the heart
itself. Speaking for a group of distinguished pathologists and statisticians,*
Dr. Hammond outlined the preliminary results of a painstaking study
begun seven years ago. At the East Orange, N.J.. Veterans
Administration Hospital, lung tissue was obtained from 227
postmortems, put on microscope slides, and carefully examined by
pathologists. The hundreds of slides were identified only with coded
numbers, and pathologists did not know their origin. Later
statisticians were able to match the pathological findings with the
histories of the dead patients. The results of the study added up to an
elaborate description of progressive smoke damage. Subjected to Stress. Deeply inhaled smoke, the researchers found,
irritates the cells that line the tiniest chambers of the lung
. The walls of the alveoli thicken, lose their elasticity and
much of their ability to do their vital job of exchanging carbon
dioxide for oxygen. Subjected to sudden stress—such as a cough or
sneeze—the alveolar walls rupture; part of the lung becomes useless. Even while it is attacking the alveoli, dense smoke also damages the
small arteries that carry blood to the lung surface for oxygenation.
The artery walls become fibrous and thickened. Soon, internal deposits
on the thickened walls make the arteries so narrow that little blood
can get through. Eventually many tiny arteries are blocked completely. Damaging Chain. These two sets of events alone would be enough to
explain why thousands of Americans are “lung cripples,”
suffering from what most U.S. doctors call pulmonary fibrosis and chronic emphysema. But the damaging
chain of events runs on. The destruction of smaller blood vessels in the lung and the thickening
of slightly larger ones increases the blood pressure in the pulmonary
arteries and puts a strain on the right side of the heart. It also prompts the left side of the heart to work harder to pump blood
against increased resistance. A healthy heart could probably stand the
extra work; a heart already weakened by other difficulties might fail.
