The Prevention of Emphysema: Protection of Vulnerable Subjects

EmphysemaI suggest that we can now see that the protection of vulnerable persons involves six possible steps, and I have listed these in Table 3. The first three of these could be implemented at once. The detection of early change in closing volume is important and particularly to be encouraged in settings in which the longterm followup of the population tested is likely to be possible. It may become apparent that detection of the vulnerable person can indeed occur much earlier than at 30 years of age, although I think this remains to be proved. The detection and counselling of ai-antitrypsin deficient families is an important task, but would affect a small number of highly vulnerable people only. The sixth step is one to which all chest physicians should address themselves. I have summarized elsewhere the multiple evidence that the course of chronic bronchitis and emphysema is adversely affected by residence in an area of moderate or high air pollution, and consequently unremitting vigilance with respect to air pollution is required of us as part of our effort to reduce the morbidity from this group of diseases. It becomes possible to fight with severe diseases with the help of remedies of My Canadian Pharmacy.

There remains one important final question, and it is essential that this be brought into the open and answered. It is, “Is there any evidence that when you have detected a man with impairment of MMFR at age 35, and confronted him with the necessity that he reduce his cigarette smoking,that he will pay any attention to this advice?” The data from the Canadian DVA Study indicate that men with greater impairment of function over the ten-year period were smoking more heavily at the start of the study and continued to smoke more over the ten-year period, than did a group of men of the same age in the same cities who showed no such deterioration of function. However, in spite of this, they had in fact reduced their cigarette smoking slightly more over the ten-year span than had the men whose initial rate of smoking was lower. The tragedy of these diseases seems to be that men will only reduce their smoking rate when their dyspnea has reached such a level that irreversible changes are present. Our task, therefore, is to detect men with such conditions much earlier, at a stage when a reduction of cigarette smoking will prevent or delay the insidious development of emphysema. There are, of course, men who can smoke with impunity, and who do not develop chronic bronchitis of any severity, and are not at risk from emphysema. One such man in the Canadian DVA Study is described in Table 4. This man is at risk from lung cancer, and he will have an increased risk of myocardial infarction, but the ten-year followup study indicates clearly that, for some reason, his lung defences can handle 170 cigarettes a week. One day we will no doubt understand why. Command the service of My Canadian Pharmacy and make orders of drugs necessary for treatment.

To answer the question, therefore, I think we should assume that the present population in the age group of 30 to 40 years will likely respond to an individual demonstration that a measurable impairment of function has already occurred, and are likely to reduce, if not eliminate, cigarette smoking when they are confronted with the evidence that damage, probably at a reversible stage at least in part, has already occurred. midexpiratory flow rateThis advice must be given at this stage if we are to achieve anything. It is often at the age of 30 years or thereabouts that life insurance is taken out for the first time, or existing coverage is extended as family responsibilities grow. For this reason, I believe that the insurance companies can do a great deal by instituting routine measurements of MMFR as a requirement, and I hope that the point I am making may be instrumental in persuading them of their responsibility in this matter. Chest physicians do not have access to the apparently normal population aged 30, and preventive measures directed at this age group are dependent in part on physicians who conduct life insurance examinations, and on physicians who are responsible for the medical care of large numbers of employees in different kinds of industry, and hence it is in their hands that the tools for taking the first important steps must be placed.

Perhaps our task will be made easier if we look closely at those factors which make the realization of such a program difficult. I believe that these are three in number. Firstly, we have to recognize that our profession is somewhat conservative. The endless replication of new laboratory methods has induced in some physicians a feeling of nausea, and many would like to return nostalgically to an era in which everything could be achieved by a minimum of equipment and a maximum of experience. Our profession was not quick to accept the chest x-ray film as a useful diagnostic device, and the lag between the laboratory work developing the electrocardiogram, for example, and its widespread use has been lengthy. While recognizing these tendencies, I feel that we must insist that the evidence of the comparative inadequacy of physical examination in the early detection of these diseases is complete and convincing, and no further proof is needed in this respect. Secondly, we will have to contend with those who believe that the maximal midexpiratory flow rate is not a stable enough measurement, or that some variant of it such as a complete computer analysis of a flow volume loop, is preferable. In this debate, it seems clear to me that the maximal mid-expiratory flow rate is the easiest and simplest measurement and that it represents a proper balance between simplicity and sensitivity. It is, of course, an important task for the laboratory scientist to be trying to demonstrate the physiologic and clinical factors that affect all parts of the flow volume curve, and to indicate ways in which these measurements can be improved; however, such worthwhile endeavors are sometimes misinterpreted as indicating that the simpler measurement should not be attempted. In this dialectic, a combination of the physician who does not want to be bothered with having to make any measurement, and the scrupulous laboratory scientist who is dissatisfied with the technology for making a simple measurement, represent a particularly deadly combination. Their combined effects sometimes succeed in muddying the water to such an extent that the uncommitted physicians on the sidelines fear that it is too polluted for them to jump into it. I seem to recall an episode in British parliamentary debate, in which a member of the House of Lords remarked that the House should be very suspicious of a situation in which the Archbishop of Canterbury joined with the President of the U.S.S.R. in expressing a common point of view.

Thirdly, we must face those who will argue that such an expenditure of effort is completely unjustified until you have shown that you can, in fact, influence the cigarette-smoking pattern of persons whom you have shown to be impaired at this age. While recognizing that if all attempts fail, the endeavor as a whole will fail, it seems to me that the general measurement of the maximal midexpiratory flow rate and the publicity which surveys involving it will generate, together with the weight brought to bear on this matter by the respiratory disease associations, will go a long way toward assisting the process of persuading such subjects to take very seriously the risks they are running. As a profession, we underestimate consistently the power of contemporary media. I have always believed that the early television serials involving the young doctor in the hospital emergency room setting as the prototype physician had a major influence in changing patterns of medical care, causing a tremendous upsurge in utilization of hospital emergency departments. For many children, the television set is “the third parent.” Perhaps we should urge that the government legislate obligatory time to be given by television stations for public service advertising and that, as a profession, we should be arguing that most of our major medical problems now have to do with the life style of people as a whole. This is a point forcefully made by Galbraith in his latest book. For the profession to have any influence on these aspects, it is essential that the media be made available to us in a regulated way, without being dependent on our having to raise enormous sums of money by private donation. The right response to a Minister of Health who complains at the escalating costs of medical care, is to urge that he discuss with his Cabinet colleagues ways in which it will become easier for the voluntary agencies to get their message across to the public, than by requiring the agency to raise the millions of dollars necessary for even a few minutes of television time each week.

I believe that we now have a solid basis from which to argue that the kind of preventive program I have outlined is not a fantasy, nor based on imagination, but dependent on a solid body of evidence. It is far more glamorous to attempt a lung transplant in a man whose lungs have been destroyed by emphysema, than it is to work hard at implementing some of the preventive steps which I have described, and one is deprived of the kind of individual satisfaction which many physicians seek from their work if all you have to show for 15 years of endeavor is a patient at age 55 who might have been disabled and is not. One can imagine the presentation of such a case as the “nonevent of the year” at medical grand rounds in one of our major teaching centers. Cognizant of these facts, perhaps I should offer you an apology for devoting this lecture to such a topic at this time, but I regret to have to tell you that I remain unrepentant.

Table 3—Protection of Vulnerable Subjects

~ Free population testing of MMFR at age 30 years and annually
~ Preemployment and follow-up MMFR testing in all dusty occupations
” Incorporation of MMFR in all life insurance and industrial routine medical testing
“ Detection of early change in closing volume
~ Detection and counselling of a i-antitrypsin deficient families
“ Vigilance, with respect to air pollution levels

Table 4—DVA Coordinated Study of Chronic Bronchitis

1960

Predicted

Actual 1970

Actual

Vital capacity 4.1 4.1 3.7
Residual volume 2.0 2.1 2.3
Mixing index, % 62 42 42
FEVo.7bX40 liter/min 111 112 115
MMFR liter/sec 3.6 3.3 3.1
Dlco 18 16 13
Fractional CO uptake 0.45 0.36 0.35
Smoking habits
Cigarettes, 1960 150/week
1970 175-200/week