Report Cites Cigarettes As Lung Cancer Cause

Press, Volume CIII, Issue 30337, 13 January 1964, Page 11

Report Cites Cigarettes As Lung Cancer Cause

(N.Z.P. A.-Reuter—Copyright) WASHINGTON, January 11. Leading American scientists today reported that cigarette smoking was a cause of lung cancer and called for “remedial action.” They said that in addition to being a cause of lung cancer, cigarette smoking “contributes substantially to mortality from certain specific diseases and to the overall death rate.

In a 150,800-word report, they said the average male cigarette smoker ran a nine to 10-fold risk of contracting lung cancer, with a heavy smoker facing 20 times the risk of the nonsmoker. Cigar and pipe smoking were found to be of little significance in comparison with cigarettes. The report did not come to any conclusion on the question of filter-tipped cigarettes.

Dr. Luther Terry, the United States SurgeonGeneral, who set up the committee of nine doctors and a professor under his chairmanship to study the effects of smoking on health, told reporters: “I can assure the committee that we will move promptly to determine what remedial health measures the Public Health Service should take.” Neither the committee nor Dr. Terry dealt with the specific measures that might be taken. The committee found that cigarette smoking was related to- higher death rates in a number of disease categories.

“In view of the continuing and mounting evidence from many sources,” the report said, “it is the judgment of the committee that cigarette smoking contributes substantially to mortality from certain specific diseases and to the over-all death rate.” The committee said that in coronary artery disease, the leading cause of death in the United States, the death rate was 70 per cent higher for cigarette smokers.

Terry’s Advice Dr. Terry was asked at a press conference in connexion with the publication of the report what advice he would give his patients. “I would advise anyone to discontinue smoking cigarettes, but if he were to continue smoking he should do so in appreciation of the health hazard,” replied Dr. Terry. He acknowledged that he himself had been a cigarette smoker, but was now smoking a pipe and at times a few cigars. He said this was a problem of national concern and national consideration, and that remedial action would depend on the reaction of many different sections of the population. He declined to say that the committee’s report constituted the official position of the Public Health Service. On the other hand he said “I think I can assure you that it is an excellent report.”

Now Smokes Pipe Another committee member said he had smoked cigarettes, but now smoked a pipe. Yet another member of the panel, asked if he would continue smoking cigarettes, replied: “I don't know for sure yet.” Dr. Emmanuel Farber, another committee member, said he smoked a pipe, “but I smoke a lot of cigarettes.” Dr. Leonard M. Schuman, another committee member, said to laughter: “I refrained from changing my habits so that prejudgments ■ might not be interpreted.” The report was 14 months in preparation and embraced all the seven major previous studies made in the field of smoking and health, including that undertaken in Britain in 1956 in a questionaire sent to all members of the British medical profession. Filter Tips Reporters were told that the committee felt there was not enough evidence to make a judgment at present on filter-tip cigarettes and their effects on hazards to health. The principal findings were given by the committee as follows: “Cigarette smoking is associated with a 70 per cent increase in the agespecific death rates of males, and to a lesser extent with increased death rates of females. “The total number of deaths causally related to cigarette smoxing in the United States population cannot be accurately estimated. In view of the continuing and mounting evidence from many sources, it is the judgment of the committee that cigarette smoking contributes substantially to mortality from certain specific diseases and to the over-all death rate.” Lung Cancer “Cigarette smoking is casually related to lung cancer in men, the magnitude of the effect of cigarette smoking far outweighs all other factors. The data for women, though less extensive, points in the same direction. “The risk of developing lung cancer increases with duration of smoking and the

number of cigarettes smoked a day, and is diminished by discontinuing smoking. In comparison with non-smok-ers, average male smokers of cigarettes have approximately a nine to 10-fold risk of developing lung cancer and heavy smokers at least a 20-fold risk. “The risk of developing cancer of the lung for the combined group of pipe smokers, cigar smokers, and pipe and cigar smokers is greater than for non-smokers, but much less than for cigarette smokers. “Cigarette smoking is much more important than occupational exposures in the causation of lung cancer in the general population.”

Chronic Bronchitis And Emphysema “Cigarette smoking is the most important of the causes of chronic bronchitis in the United States, and increases the risk of dying from chronic bronchitis and emphysema. “A relationship exists between cigarette smoking and emphysema, but it has not been established that the relationship is causal. Studies demonstrate that fatalities from this disease are infrequent among non-smokers. “For the bulk of the population of the United States, the relative importance of cigarette smoking as a cause of chronic broncho-pul-monary disease is much greater than atmospheric pollution or occupational exposures.”

Cardiovascular Diseases It is established that male cigarette smokers have a higher death rate from coronary artery disease than non-smoking males. “Although the causative role of cigarette smoking in deaths from coronary disease is not proven, the committee considers it more prudent from the public health viewpoint to assume that the established association has causative meaning than to suspend judgment until no uncertainty remains. “Although a causal relationship has not been established, higher mortality of cigarette smokers is associated with many other cardiovascular diseases, including miscellaneous circulatory diseases, other heart diseases, hypertensive heart disease, and general arteriosclerosis.” Other Cancer Sites “Pipe smoking appears to be causally related to lip cancer. Cigarette smoking is a significant factor in the causation of cancer of the larynx. “The evidence supports’the belief that an association exists between tobacco use and cancer of the oesophagus, and between cigarette smoking and cancer of the urinary bladder in men, but the data are not adequate to decide whether these relationships are causal. “Data on an association between smoking and cancer of the stomach are contradictory and incomplete.” On the basis of prolonged study and evaluation of many lines of converging evidence, the committee said it made the following judgment, which was printed in bold type in its report:

“Cigarette smoking is a health hazard of sufficient importance in the United States to warrant appropriate remedial action.”

Tobacco Habit It said the habitual use of tobacco was related primarily to psychological and social drives, reinforced and perpetuated by the pharmacological actions of nicotine. . In a passage on the chemistry of tobacco and tobacco smoke, the committee said there was abundant evidence that cancer of the skin could be induced in man by industrial exposure to sopts, coal tar, pitch, and mineral oils, aL of which contained various polycyclic aromatic hydrocarbons proven to be carcinogenic in many species of animals. “Some of these hydrocarbons are also present in tobacco smoke,’’ the committee said “It is reasonable to assume that these can be carcinogenic for man also.” It also said that components of the gas phase of cigarette smoke had been shown to produce various undesirable effects on test animals or organs. One of these effects was suppression of ciliary transport activity, an important cleansing function in the trachea and bronchia. Sources Of Evidence The report said that the main evidence had been secured through clinical and pathological observation of conditions occurring in men, women and children in the ' course of their lives, and by I the application of epidemiological and statistical methods. It said that lung cancer deaths in 1962 in the United States totalled 41.000, compared to less than 3000 in 1930. The committee said this extraordinary rise had not been recorded for cancer of any other part of the body. Nearly 70,000,000 persons in

the United States consumed tobacco regularly, it said. The committee noted that “observations of thousands of patients and autopsy studies of smokers and non-smokers show that many kinds of damage to body functions and to organs, cells, and tissues occur more frequently and severely in smokers. Extensive studies consistently showed that chronic cough, sputum production, breathlessness, chest illness and decreased lung function occurred more often in cigarette smokers than in nonsmokers. A total of 1,123,000 men entered the seven previous studies and all provided usable histories of smoking habits, the committee said. Of the total, 37,391 men died during the studies.

Mortality Ratios

The report said that in the combined results from the seven studies, the mortality ratio of cigarette smokers over non-smokers was particularly high for a number of diseases —cancer of the lung (10.8), bronchitis and emphysema (6.1), cancer of the larynx (5.4), all cancer (4.1), cancer of the oesophagus (3.4), peptic ulcer (2.8), and the groqp of other circulatory diseases (2.6). For coronary artery disease the mortality ratio was 1.7. The committee said that the seven studies showed that: the death rates for men smoking less than five cigars a day were about the same as for non-smokers. For men smoking more than five cigars daily, death rates were slightly higher. "There is some indication that these higher death rates occur primarily in men who have been smoking more than 30 years and who inhale smoke to some degree.

Pipe Smokers “The death rates for pipe smokers are little if at all higher than for non-smokers, even for men who smoke 10 or more pipefuls a day and for men who have smoked pipes more than 30 years.” “Nicotine is rapidly changed in the body to relatively inactive substances with low toxicity. The chronic toxicity of small doses of nicotine is low in experimental animals. “These two facts, when taken in conjunction with the low mortality ratios of pipe and cigar smokers, indicate that the chronc toxicity of nicotine in quantities absorbed from smoking and other methods of tobacco Use is very low and probably does not represent an important health hazard. Benefits Of Smoking “The significant beneficial effects of smoking occur primarily in the area of mental health and the habit originates in a search for contentment. “Since no means of measuring the quantities of these benefits is apparent, the committee finds no basis for a

judgment which would weigh benefits against hazards of smoking as it may apply to the general population," the report said. The committee said that social stimulation appeared to play a major role in a young person’s first experiments with smoking. It said that no scientific evidence supported the popular hypothesis that smoking among adolescents was an expression of rebellion against authority. “Individual stress appears to be associated more with fluctuations in the amount of smoking than with the prevalence of smoking,” it said. “The overwhelming evidence indicates that smoking—its beginning habitation, and occasional discontinuation—is to a very large extent psychologically and socially determined.

Wide Distribution The report will be distributed to 200,000 physicians in the United States as well as to ministers of health in other countries. Dr. Terry was asked at the press conference how American doctors were likely to react to the report. He said that each physician must make an individual judgment on the report. He should use the report and any other information available to him. Effective remedial steps would depend on the judgment not only of the medical profession but of many agencies involved. Dr. Terry said that an analysis was already underway in the Public Health Service. He said he would certainly advise children not to start smoking. Dr. Terry said that the committee's recommendations and conclusions were unanimous. Asked when recommendations for remedial action might be made, he said that the matter was of such significance and importance, “I don't believe there will be any foot-dragging in terms of exploring what actions are apnropriate." He said he would be anxious to see what would be done by the American Medical Association It was stated that the committee did consider putting into the report a conclusion about what effect there would be on longevity figures if there were no smoking at all. Dr. James M. Hundley, the Assistant Surgeon-Gen-eral, said it involved making so many assumptions that the committee had felt it should not attempt to come to a conclusion.