May 19, 1988 - Department of National Health and Welfare, Ottawa: John W. Davies, Walter ... Winnipeg; Irvin Broder, Gage Research Institute, Toronto;Sonia. Buist ... Carruthers, University of Western Ontario, London; William. Chodirker ...
I Workshop Report
Highlights of national workshop on asthma, Ottawa, May 19,1988 Donald T. Wigle, MD, PhD, MPH
national workshop on asthma, held May 19, 1988, in Ottawa, was convened by the Laboratory Centre for Disease Control (LCDC), Department of National Health and Welfare, to bring together experts from various disciplines to make recommendations on the following general needs and priorities. * To consider the general scope and design of epidemiologic studies on deaths from asthma among young adults in Canada' in order to (a) formulate hypotheses on the potential causes and
A
Participants in the workshop included the following, from the Department of National Health and Welfare, Ottawa: John W. Davies, Walter Litven, Yang Mao, Howard Morrison and Donald T. Wigle, Bureau of Chronic Disease Epidemiology; Daniel G. de Jesus, Bureau of Human Prescription Drugs; Jamie Hockin and Joseph Z. Losos, Laboratory Centre for Disease Control; Marc Raizenne, Environmental Health Centre; May Smith, Health Services and Promotion Branch; and Ken Michalko and Michel Sylvain, Health Protection Branch. Also participating were the following: Anna Brancker and Cyril Nair, Statistics Canada, Ottawa; Christofer Balram, Department of Health, Fredericton; Allan B. Becker, Children's Hospital of Winnipeg; Irvin Broder, Gage Research Institute, Toronto; Sonia Buist, Oregon Health Sciences University, Portland; George S. Carruthers, University of Western Ontario, London; William Chodirker, University Hospital, London; Bob Dales, University of Ottawa; Winanne Downey, Saskatchewan Health Prescription Drug Plan, Regina; Donald Enarson, University of Alberta, Edmonton; Ruth Etzel, US Centers for Disease Control, Atlanta, Georgia; Stefan Grzybowski, Vancouver General Hospital; Claire Infante-Rivard, School of Occupational Health, Montreal; Gary Liss, Ontario Ministry of Labour, Toronto; Jure Manfreda (chairman), Respiratory Hospital, Winnipeg; Carolyn Pim, BC Centre for Disease Control, Vancouver; Francis S. Rolleston, Medical Research Council of Canada, Ottawa; Bruce P. Squires, Canadian Medical Association, Ottawa; William H. Yang, Canadian Society of Allergy and Clinical Immunology, Ottawa; and Moira Yeung, Vancouver General Hospital.
Copies of the report of the workshop are available from Dr. Joseph Z. Losos, Director general, Laboratory Centre for Disease Control, Department of National Health and Welfare, Tunney's Pasture, Ottawa, Ont. KIA OL2.
Reprint
requests to: Dr. Donald T. Wigle, Bureau of Chronic Disease Epidemiology, Laboratozy Centre for Disease Control, Department of National Health and Welfare, Tunney's Pasture, Ottawa, Ont. KIA OL2
(b) recommend general design and analysis features required for such epidemiologic studies. * To stimulate applications to the National Health Research and Development Program and the Medical Research Council of Canada for research into the causes of death from asthma and the optimal treatment of asthma. * To recommend medical, educational or regulatory measures that could be implemented immediately to reduce the risk of death from asthma. Asthma is a major health problem, affecting over 500 000 Canadians.2 It begins early in life and affects more than 140 000 children under 15 years of age, more than 170 000 people aged 15 to 34 years and about 200 000 older people. Rates of death from asthma among young adults decreased from the 1950s to about 1970 but have since tripled.- Rates of hospital admission increased sharply between 1970 and 1984, especially for patients less than 15 years of age.1 Dr. Carolyn Pim, federal field epidemiologist, reported preliminary data for British Columbia that indicate that between 1973 and 1984 about 60% of medically certified deaths from asthma in the 15to 34-year age group had occurred suddenly outside hospital. There has been no systematic investigation or active surveillance of such deaths in Canada. LCDC officials presented the results of timetrend analyses of rates of hospital admission and death from asthma. The outstanding feature, apart from the previously reported trends,1 was a marked seasonal effect, the rates being highest in late summer and early fall. Dr. Jure Manfreda, from Winnipeg, chaired the 1-day workshop, which was attended by 33 people representing academic researchers, granting agencies, federal and provincial health officials, the US Centers for Disease Control and the US Task Force on Fatal Asthma. The participants focused on the problems, opportunities, needs and methods available for research on asthma and concluded that the epidemic of deaths from asthma among young adults CMAJ, VOL. 140, MARCH 15, 1989
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is real and that resources are needed to address the identified research and education needs. Canada is well suited, because of its universal health care system and record-linkage technology, for the long-term follow-up studies required to define the natural history of asthma and assess potential risk factors. Research issues should be addressed through a coordinated, multicentre program with formal links to similar programs in other countries.
Recommendations Diagnostic criteria
* The diagnosis of asthma should be based on a compatible clinical history and the presence of either variable airflow obstruction or bronchial hyperreactivity. * "Near-fatal" asthma should be defined as the presence of hypercapnia or a requirement for intubation during a severe asthma attack. * Death should be considered to have been from asthma when, in the absence of other causes, the person was known to have asthma and autopsy specimens show characteristic pathologic changes in the lungs or, if an autopsy was not performed, either the person had experienced a near-fatal attack of asthma before death or the death was associated with complications of asthma such as pneumothorax, cor pulmonale, aspiration or pulmonary edema. * The severity of asthma should be categorized according to the treatment history and the results of lung function tests.
Surveillance * Descriptive epidemiologic studies are needed to better define the distribution of cases of severe asthma and deaths from asthma; such studies should be conducted among high-risk populations (considering residence and socioeconomic status) and among time-space clusters, including daily, weekly or seasonal epidemics. * Hospital chart reviews are needed to obtain information on factors that may contribute to the risk of severe asthma or death from asthma and to assess possible trends of diagnostic labelling. * Coroners' reports are potentially valuable sources of information on the estimated two-thirds of deaths from asthma among young adults that occur suddenly outside hospital. There is an urgent need to improve and standardize coroners' reports with such information as a recent history of disease and results of chemical and pathological analysis of tissue, blood and urine specimens. * False-negative diagnoses of asthma on death certificates should be sought under several disease categories. 0 Case reviews of deaths from asthma, similar to those conducted by Pim and her colleagues 672
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in British Columbia, should be performed in other provinces. * Information on trends in drug use (including overuse and underuse) among people with asthma could be obtained from the Saskatchewan Drug Plan. * There is a need for ecologic studies of the relation between visits or admission to hospital for asthma and changes in climate (humidity and temperature), air quality (presence of pollens, fungal spores and toxic chemicals) and rates of respiratory tract infection.
Epidemiologic research * Case-control studies of severe asthma and deaths from asthma are needed to assess the role of suspected causal factors. * Epidemiologic studies of young people with asthma are urgently required because so little is known about the environmental causes of asthma. * Research should distinguish between factors that cause asthma (risk factors) and factors that aggravate or alleviate pre-existing asthma (prognostic factors). * Samples should be large enough to allow study of interactions between risk and prognostic factors. * Risk factors should be analysed and compared for various subgroups: deaths, in or out of hospital, and near-fatal and other severe cases of asthma. * Rapid methods of ascertainment are needed to obtain reliable information on recent exposure before near-fatal or fatal episodes of asthma. * Exposure to a broad range of potential risk factors should be assessed through standardized questionnaires and assays of biologic samples. * Cohort studies of people with severe asthma can determine the natural history of severe asthma and risk factors for severe attacks and death. * Information from the Saskatchewan Drug Plan may help assess the relation between drug use patterns and severe or fatal episodes of asthma by computer linkage of drug use, health care use and records of death. * Meta-analyses of the existing literature on prognostic studies of asthma are needed to consolidate knowledge and guide future research.
Clinical management and research * Treatment standards for asthma, determined through clinical trials, are needed. * For clinical trials consensus is needed on the definition of asthma severity categories, treatments to be tested and end-points of trials. * Education of physicians and people with asthma must apply current knowledge of optimal treatment and self-management.
* Treatment trials for long-term management of asthma, which are almost nonexistent, are badly needed. * Workshops can synthesize current knowledge of the optimal treatment of asthma. * Detailed recent and long-term treatment histories should be collected systematically for epidemiologic research studies.
National coordination
* A national task force representing diverse interest groups should be established to develop and promote research and education efforts and to liaise with similar groups in other countries. * Multicentre epidemiologic and clinical studies of asthma in Canada should be supported by a coordinating centre chosen through a competitive, peer-reviewed process.
References 1. Mao Y, Semenciw R, Morrison H et al: Increased rates of illness and death from asthma in Canada. Can Med Assoc J 1987; 137: 620-624 2. Wigle DT: Prevalence of selected chronic diseases in Canada, 1978-79. Chronic Dis Can 1982; 3: 8-9
No easy task
Students must tolerate tiresome speakers because they cannot help themselves by walking out. In this respect students are often more courteous than their teachers. To teach properly is no easy task and cannot be done by haphazard methods. In my own experience as a medical student I recall that we had a very brilliant medical scholar as a teacher who could not make his talks interesting. His ward rounds were called by facetious students "shifting dullness".
Meetings continued from page 662 June 2-3, 1989: Update in Common Respiratory Problems for Primary Care Physicians (in conjunction with the Canadian Lung Association) New World Harbourside Hotel, Vancouver Continuing Education in the Health Sciences, 105-2194 Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1W5; (604) 228-2626 June 15-17, 1989: American College of Physicians Course: Current Issues in Gastroenterology (cosponsored by the Royal College of Physicians and Surgeons of Canada and the Canadian Association of
Gastroenterology) Holiday Inn, Kingston, Ont. Gastroenterology Courses, c/o Events Management Inc., 209-4 Cataraqui St., Kingston, Ont. K7K 1Z7; (613) 547-5093 June 18-22, 1989: Canadian Dietetic Association Annual Conference: Shaping the Future Edmonton Convention Centre Lynn Snelson, publicity cochairperson, '89 Conference Committee, 445 Lessard Dr., Edmonton, Alta. T6M 1B6; (403) 484-8811, ext. 626 or 643
June 24, 1989: Cosmetic Surgery Symposium Cosmetic Surgery Hospital, Woodbridge, Ont. Mrs. P. Hewitt, secretary, Canadian Society for Aesthetic (Cosmetic) Plastic Surgery, 4650 Highway 7, Woodbridge, Ont. L4L 1S7; (416) 831-7750 or 1-800-263-4429 Oct. 2-6, 1989: 31st Annual Radiation Protection Course Chalk River Nuclear Laboratories, Chalk River, Ont. Mrs. D.J. TerMarsch, course coordinator, Physics and Health Sciences, Atomic Energy of Canada Limited, Chalk River Nuclear Laboratories, Chalk River, Ont. KOJ 1JO; (613) 584-3311, ext. 4729
Oct. 28, 1989: 9th Annual Fall Sports Medicine
Symposium Instructional Resources Centre, University of British Columbia, Vancouver Continuing Education in the Health Sciences, 105-2194 Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1W5; (604) 228-2626 Nov. 6-10, 1989: International Health Symposium Galeria Plaza Hotel, Mexico City Dr. W.A. Black, Provincial Laboratory, British Columbia Centre for Disease Control, 828 W 10th Ave., Vancouver, BC V5Z 1L8; (604) 660-6029, FAX (604) 660-6066
Thomas G. Orr (1884-1955) Feb. 2-4, 1990: 10th Annual Whistler Sports Medicine
Symposium Whistler Conference Centre, Whistler, BC Continuing Education in the Health Sciences, 105-2194 Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1W5, (604) 228-2626 CMAJ, VOL. 140, MARCH 15, 1989
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