remote areas of Canada; practice in such areas will be more attractive to young physicians; and once radiotelemetry of cardiovascular data is available, patients will receive expert care locally without expensive transport to major medical centres. We are being left far behind in the prevention of cardiovascular disease. We have the expertise in computerization and epidemiology and yet little is being done. Let us attack the problem before the heart attack stops us.
J.A. MILLIKEN, MD
Department of medicine Queen's University Kingston, ON
3. GENEST J: The hypertensive patient (E). Thid, p 747 4. MCCAUOHAN D, LITTMANN D, PIPRERGER HV:
P.M. RAUTAHARJU, MD, PH D
Biophysics and bioengineering research laboratory Faculty of medicine Daihousie University Halifax, NS
5. 6.
References 1. WiLsas JA, BARROW JG: Hypertension - a community program. Am J Med 52: 653, 1972
7.
2. SILVERBERO DS, SMITH ESO, JucHLI B, et al:
8.
Use of shopping centres in screening for hypertension. Can Med Assoc J 111: 769, 1974
Computer analysis of the orthogonal electrocardiogram and vectorcardiogram in 939 cases with hypertensive cardiovascular disease. Am Heart 1 85: 467, 1973 FERRER MI: The significance of axis deviation (E). Chest 61: 443, 1972 PIPSERGER HV, MCCAUGHAN D, Lr[TMANN D, et al: Clinical application of a second generation electrocardiographic computer program. Am I Cardiol 35: 597, 1975 KANNEL WB, MCNAMARA PM, FEINLEIB M, et al: The unrecognized myocardial infarction. Fourteen-year follow-up study in the Framingham Study. Geriatrics 25: 75, 1970 BONNER R: Computerized interpretation of ECG. Paper presented at the 1975 Engineering Foundation Conference, Rindge, New Hampshire
The future is now The catch phrase, "the future is now", which was used during a recent provincial election campaign, is also pertinent to the practice of medicine. Are some of the health problems facing us today the result of iatrogenic medicine practised by our predecessors? Are we just as guilty of creating problems for those who follow us? I believe the answer to both questions is "Yes". Two examples are the common use of diethylstilbestrol (DES) and the widespread, loose reliance on radiographs. Several years ago The Canadian Medical Association expressed concern over the continued prescription of DES, particularly as a postcoital contraceptive. This concern was expressed in other countries because the presence of vaginal adenosis and malignant lesions in the teenage daughters of women given DES in early pregnancy appeared to be increasing. A recent study in the United States showed that a high percentage of male offspring of mice given DES in early pregnancy had reduced sperm count and motility, and in some cases complete sterility.' Health and Welfare Canada directed that DES should not be considered as a postcoital contraceptive except in cases of rape or incest, yet some physicians still prescribe the drug in cases of possible pregnancy when an abortion is unlikely to be performed should estrogen not produce bleeding. In 1972 a CMA committee was formed to examine radiation hazards. Included on this committee were representatives from the health programs branch and the radiation protection bureau of Health and Welfare Canada, The Canadian Association of Radiologists, the Canadian Public Health Association, the Canadian Thoracic Society and the Canadian Tuberculosis and Respiratory Disease Association. The recommendations made by the committee, which were approved by
General Council in 1973, indicated that routine screening should not be carried out, except in special circumstances and where applicable to certain high-risk segments of the population. But physicians still order routine chest radiographs, as do life insurance companies and certain industries; hospitals whose regulations require a routine admission radiograph are also guilty. Over 60% of Canadians with access to modern medical and dental care are exposed to some form of radiography each year. Experts believe that well designed and properly used medical x-ray equipment could reduce unnecessary exposure to about 10% of its present level without loss of diagnostic information. Epidemiologic studies have linked radiation to certain conditions: carcinogenesis, accelerated ageing, genetic changes and blood dyscrasias. In the US a study2 by the National Academy of Sciences suggested that x-rays cause 4000 deaths in that country each year. Dentists and chiropractors also contribute to this major health hazard. Does your dentist protect your child's body, particularly the gonadal area, from x-rays with a lead apron? And how many women are exposed to dental x-rays in early pregnancy without protection? Reliable authorities believe that the "14 x 36 full-trunk x-ray", so beloved by the chiropractor, presents one of the greatest radiation hazards, and published figures show that chiropractors subject over 90% of their patients to this type of exposure. Obviously patients, particularly children and women in the reproductive age group, receive minimum protection, and no steps are being taken to reduce the hazard. Physicians should be aware of, and concerned about, radiation procedures carried out by their predecessors. The work of Stewart and associates3 in the United Kingdom, linking childhood
186 CMA JOURNAL/FEBRUARY 7, 1976/VOL. 114
leukemia with prenatal maternal radiation, is well documented. Not as well known is the documented evidence of malignant thyroid lesions appearing in adults 20 to 30 years after radiation exposure of the head, neck and upper thorax.4 Several articles have emphasized the need for physicians to review their files and patients' histories for evidence of such exposure so that these patients may be followed up.5'6 In a study of operations for thyroid carcinoma in adults the University of Chicago thyroid study unit found that in 40% of such cases the patient had a history of neck irradiation.4 Scientists have expressed the view that about 40 rads is the upper limit of safety for total body exposure during an average lifetime. This estimate excludes therapeutic radiation, as might be given in treatment of malignant conditions. It is important that we do everything possible to minimize health hazards to future generations. Our whole approach to man-made health and environmental hazards should be carefully examined so that primum non nocere becomes more than a cliche. JOHN S. BENNETr, MD
Coordinator, Council on Community Health The Canadian Medical Association
References 1. McLACHLAN JA, NEWBOLD RR, BULLOCK B: Reproductive tract lesions in male mice exposed prenatally to diethylstilbestrol. Science 190: 991, 1975 2. Advisory committee on the biological effects of ionizing radiations, National Academy of Sciences/National Research Council: The Ef-
fects on Populations of Exposure to Low Levels of Ionizing Radiation, Washington, US Dept of Health, Education and Welfare! Environmental Protection Agency, 1972
3. STEWART A, WEBB J, GILES D, et al: Malignant disease in childhood and diagnostic irradiation in utero. Lancet 2: 447, 1956
4. DEGRoo.r L, PALOYAN E: Thyroid carcinoma and radiation. A Chicago endemic. JAMA 225: 487, 1973
5. REFETOFF 5, HARRISON J, KARANFIL5KI BT, et al: Continuing occurrence of thyroid carcinoma after irradiation to the neck in infancy and childhood. N EngI J Med 292: 171, 1975
6. BRAVERMAN LE:
Consequences of thyroid
radiation in children (E). Ibid, p 204
J.A. MILLIKEN, MD
Department of medicine Queen's University Kingston, ON
3. GENEST J: The hypertensive patient (E). Thid, p 747 4. MCCAUOHAN D, LITTMANN D, PIPRERGER HV:
P.M. RAUTAHARJU, MD, PH D
Biophysics and bioengineering research laboratory Faculty of medicine Daihousie University Halifax, NS
5. 6.
References 1. WiLsas JA, BARROW JG: Hypertension - a community program. Am J Med 52: 653, 1972
7.
2. SILVERBERO DS, SMITH ESO, JucHLI B, et al:
8.
Use of shopping centres in screening for hypertension. Can Med Assoc J 111: 769, 1974
Computer analysis of the orthogonal electrocardiogram and vectorcardiogram in 939 cases with hypertensive cardiovascular disease. Am Heart 1 85: 467, 1973 FERRER MI: The significance of axis deviation (E). Chest 61: 443, 1972 PIPSERGER HV, MCCAUGHAN D, Lr[TMANN D, et al: Clinical application of a second generation electrocardiographic computer program. Am I Cardiol 35: 597, 1975 KANNEL WB, MCNAMARA PM, FEINLEIB M, et al: The unrecognized myocardial infarction. Fourteen-year follow-up study in the Framingham Study. Geriatrics 25: 75, 1970 BONNER R: Computerized interpretation of ECG. Paper presented at the 1975 Engineering Foundation Conference, Rindge, New Hampshire
The future is now The catch phrase, "the future is now", which was used during a recent provincial election campaign, is also pertinent to the practice of medicine. Are some of the health problems facing us today the result of iatrogenic medicine practised by our predecessors? Are we just as guilty of creating problems for those who follow us? I believe the answer to both questions is "Yes". Two examples are the common use of diethylstilbestrol (DES) and the widespread, loose reliance on radiographs. Several years ago The Canadian Medical Association expressed concern over the continued prescription of DES, particularly as a postcoital contraceptive. This concern was expressed in other countries because the presence of vaginal adenosis and malignant lesions in the teenage daughters of women given DES in early pregnancy appeared to be increasing. A recent study in the United States showed that a high percentage of male offspring of mice given DES in early pregnancy had reduced sperm count and motility, and in some cases complete sterility.' Health and Welfare Canada directed that DES should not be considered as a postcoital contraceptive except in cases of rape or incest, yet some physicians still prescribe the drug in cases of possible pregnancy when an abortion is unlikely to be performed should estrogen not produce bleeding. In 1972 a CMA committee was formed to examine radiation hazards. Included on this committee were representatives from the health programs branch and the radiation protection bureau of Health and Welfare Canada, The Canadian Association of Radiologists, the Canadian Public Health Association, the Canadian Thoracic Society and the Canadian Tuberculosis and Respiratory Disease Association. The recommendations made by the committee, which were approved by
General Council in 1973, indicated that routine screening should not be carried out, except in special circumstances and where applicable to certain high-risk segments of the population. But physicians still order routine chest radiographs, as do life insurance companies and certain industries; hospitals whose regulations require a routine admission radiograph are also guilty. Over 60% of Canadians with access to modern medical and dental care are exposed to some form of radiography each year. Experts believe that well designed and properly used medical x-ray equipment could reduce unnecessary exposure to about 10% of its present level without loss of diagnostic information. Epidemiologic studies have linked radiation to certain conditions: carcinogenesis, accelerated ageing, genetic changes and blood dyscrasias. In the US a study2 by the National Academy of Sciences suggested that x-rays cause 4000 deaths in that country each year. Dentists and chiropractors also contribute to this major health hazard. Does your dentist protect your child's body, particularly the gonadal area, from x-rays with a lead apron? And how many women are exposed to dental x-rays in early pregnancy without protection? Reliable authorities believe that the "14 x 36 full-trunk x-ray", so beloved by the chiropractor, presents one of the greatest radiation hazards, and published figures show that chiropractors subject over 90% of their patients to this type of exposure. Obviously patients, particularly children and women in the reproductive age group, receive minimum protection, and no steps are being taken to reduce the hazard. Physicians should be aware of, and concerned about, radiation procedures carried out by their predecessors. The work of Stewart and associates3 in the United Kingdom, linking childhood
186 CMA JOURNAL/FEBRUARY 7, 1976/VOL. 114
leukemia with prenatal maternal radiation, is well documented. Not as well known is the documented evidence of malignant thyroid lesions appearing in adults 20 to 30 years after radiation exposure of the head, neck and upper thorax.4 Several articles have emphasized the need for physicians to review their files and patients' histories for evidence of such exposure so that these patients may be followed up.5'6 In a study of operations for thyroid carcinoma in adults the University of Chicago thyroid study unit found that in 40% of such cases the patient had a history of neck irradiation.4 Scientists have expressed the view that about 40 rads is the upper limit of safety for total body exposure during an average lifetime. This estimate excludes therapeutic radiation, as might be given in treatment of malignant conditions. It is important that we do everything possible to minimize health hazards to future generations. Our whole approach to man-made health and environmental hazards should be carefully examined so that primum non nocere becomes more than a cliche. JOHN S. BENNETr, MD
Coordinator, Council on Community Health The Canadian Medical Association
References 1. McLACHLAN JA, NEWBOLD RR, BULLOCK B: Reproductive tract lesions in male mice exposed prenatally to diethylstilbestrol. Science 190: 991, 1975 2. Advisory committee on the biological effects of ionizing radiations, National Academy of Sciences/National Research Council: The Ef-
fects on Populations of Exposure to Low Levels of Ionizing Radiation, Washington, US Dept of Health, Education and Welfare! Environmental Protection Agency, 1972
3. STEWART A, WEBB J, GILES D, et al: Malignant disease in childhood and diagnostic irradiation in utero. Lancet 2: 447, 1956
4. DEGRoo.r L, PALOYAN E: Thyroid carcinoma and radiation. A Chicago endemic. JAMA 225: 487, 1973
5. REFETOFF 5, HARRISON J, KARANFIL5KI BT, et al: Continuing occurrence of thyroid carcinoma after irradiation to the neck in infancy and childhood. N EngI J Med 292: 171, 1975
6. BRAVERMAN LE:
Consequences of thyroid
radiation in children (E). Ibid, p 204
