Recent observations reflecting increases in mortality from asthma

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15. 16. 17. 18. 19. 20. 21.

22.

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adults who had asthma in childhood. Am Rev Respir Dis 1980;122:609-16. McNichol KN, Williams HB. Spectrum of asthma in children. I. Clinical and physiological components. Br Med J 1973;4: 7-11. Ogilvie AG. Asthma: a study in prognosis of 1000 patients. Thorax 1962;17:183-9. Derrick EH. The significance of the age of onset of asthma. Med I Aust 1971;1:1317-19. Ryssing E. Continued follow-up investigation concerning the fate of 298 asthmatic children. Acta Paediatr 1959;48:255-60. Burrows B, Knudson RI, Lebowitz MD. The relationship of childhood respiratory illness to adult obstructive airway disease. Am Rev Respir Dis 1977;115:751-60. Burrows B, Hasan FM, Barbee RA, et al. Epidemiologic observations on eosinophilia and its relationship to respiratory disorders. Am Rev Respir Dis 1980;122:709-19. Van de Lende R. Epidemiology of chronic nonspecific lung disease (chronic bronchitis). A critical analysis of three field surveys of CNSLD carried out in the Netherlands, vol. 1. Assen: Van Gorcum & Co., N.V., 1%9:140-6. Burrows B, Halonen M, Lebowitz MD, et al. The relationship of serum immunoglobulin E, allergy skin tests, and smoking to respiratory disorders. J ALLERGY CLIN IMMUNOL 1982;70: 199-204.

23. Burrows B, Lebowitz MD, Barbee RA, et al. Interactions of smoking and immunologic factors in relation to airways obstruction. Chest 1983;84:657-61. 24. Burrows B. Possible pathogenetic mechanisms in chronic airflow obstruction. Chest 1984;85S:l2S-15s.

25. Chie NGM, Sluiter HJ, de Vries GA, et al. The host factor in bronchitis. In: Grie NGM, Sluiter I-U, eds. Bronchitis: an international symposium. Assert: Royal Van Gorcum, 1961: 43-59. 26. Barter CE, Campbell AH. Relationship of constitutional factors and cigarette smoking to decrease in l-second forced expiratory volume. Am Rev Respir Dis 1976;113:305-14. 27. Tabona M, Chen-Yeung M, Enarson D, et al. Host factors affecting longitudinal decline in lung spirometry among grain elevator workers. Chest 1984;85:782-6. 28. Taylor RG, Joyce H, Grass E, et al. Bronchial reactivity to inhaled histamine and annual rate of decline in FEV, in male smokers and ex-smokers. Thorax 1985;40:9-16. 29. Vollmer WM, Johnson LR, Buist AS. Relationship of response to a bronchodilator and decline in forced expiratory volume in one second in population studies. Am Rev Respir Dis 3985;132:3186-93. 30. Fletcher C, Peto R, Tinker C, Speizer F. The natural history of chronic bronchitis and emphysema. London and New York: Oxford University Press, 1976. 31. Shachter EN, Doyle CA, Beck GJ. A prospective study of asthma in a rural community. Chest 1984;85:623-30. 32. Bradford J. Progressive bronchospastic disease: primary obstructive emphysema. Am Pratt Digest Treat 1952;3:349-52. 33. Postma DS, Bumma J, Gimeno F, et al. Prognosis in severe chronic obstructive pulmonary disease. Am Rev Respir Dis 1979;119:357-67. 34. Postma DS, Steinhuis El, van der Weeie LTh, et al. Severe chronic airllow obstruction: can corticosteroids slow down progression? Eur J Respir Dis 1985;67:56-64.

Recent observations refiecting mortality from asthma Richard

increases in

Evans III, M.D., M.P.H. Baltimore, Md.

In 1984, Sly,’ using data provided by the National Center for Health Statistics, reviewed deaths from asthma in various age groups between 1968 and 1982. There was a decrease in deaths from asthma between 1968 and 1978; thereafter, he found a steady increase in deaths from asthma. This increase could not be accounted for by a change that had occurred in the

From the Department of Medicine and the Department of Immunology and Infectious Diseases, The Johns Hopkins Medical Institutions, Baltimore, Md. Supported in part by National Heart, Lung, and Blood Institute Grant EDC-2 5 ROl H&30532-03, National Institutes of Health. Reprint requests: Richard Evans III, M.D., M.P.H., Johns Hopkins Medical Institutions, 615 N. Wolfe St., Room 4023, Baltimore, MD 2i205.

International Classification of Diseases (ICD) coding system during the ninth revision in 1978. Under this revision, asthmatic bronchitis, formerly coded as bronchitis, was recoded as asthma. A comparability factor was calculated to account for the differences in the coding system, and even after the application of this factor, there exists an increase in mortality from asthma that currently is inexplicable. Sly has suggested that the increase might be due to an increase in prevalence of the disease or an increase in the case fatality rate. In June 1985, the prevalence, hospitalizations, and deaths from asthma in the United States were reviewed at an international workshop at the Fogarty Intemational Center.’ Deaths from asthma in the United States during two decades, 1965 through 1984, were 377

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compiled from data of the Vital Statistics System, the National Center for Health Statistics. The Vital Statistics System compiles data from death certificates collected from each of the 50 states and the District of Columbia. Approximately 2 million death certificates are filed each year. This represents the total number of deaths in the United States and is not a sampling. From 1968 to 1978, asthma as an underlying cause of death appears to have been declining. It is possible that an artifact could be affecting this impression, because from the late 1960s to the present time, there has been a general national trend for physicians to indicate on the death certificates a more general diagnosis, chronic obstructive lung disease, rather than more specific diagnoses, such as asthma, chronic bronchitis, and emphysema. After 1978 there is an increase in mortality from asthma. The death rate for 100,000 population of all ages increased from 0.9 in 1978 to 1.4 in 1982 and 1.6 (provisional) in 1984. The total numbers of reported deaths from asthma were 2688 in 1968, 1872 in 1978, and 3440 in 1983. The trend of increasing deaths from asthma since 1978 is most marked in the age group older than 45 years. The 1984 article by Sly’ and a recent presentation in 1986 by Markham et al:” to the American Academy of Allergy and Immunology have emphasized the increasing frequency of deaths from asthma in children since 1978. Markham et al. reported that in spite of a long-term downward trend by more than 25% of deaths from all causes in children (ages 1 to 14 years) between 1965 and 1985, deaths from asthma decreased from 1965 through 1977 only and have steadily increased since then. The numbers of deaths from asthma in children of all ages (1 to 14 years) were 165 in 1965, 54 in 1977, and 111 in 1983. The change in the ICD classification of asthmatic bronchitis in 1978 does not account for the increased number of deaths reported by Markham et al. in children from asthma since 1978. Regional differences (metropolitan areas 19% higher than rural areas), a preponderance of deaths in males (20% higher than in females), and high asthma death rates in black people (350% greater than white people) were also reported by Markham et al. An increase in mortality from asthma in the presence of a decreasing overall mortality from other diseases in the pediatric age group does suggest the possibility of an increased prevalence (or, as Sly suggests, an increased case fatality rate) of the disease, at least in this age group. The data from the Fogarty Conference do not indicate an increase in prevalence that would entirely account for the increased death rate. Paulozzi et al.4 have reported since the Fogarty Con-

J. ALLERGY

CLIN. IMMUNOL. SEPTEMBER 1987

ference that mortality from asthma has increased 82% in the states of Washington and Oregon. This increase was predominantly in the age group older than 75 years. In December 1985, an international symposium on status asthmaticus and asthma deaths was held at the Brown University in Providence, R.I. Several participants related a common conviction that mortality from asthma is frequently associated with inadequate assessment (by physician and patient) of the severity of the condition in a given patient and delay in the patient seeking therapy. Stableforth’ from the United Kingdom presented a detailed review of asthmatic fatalities that had occurred during the epidemic of asthma in the 1960s in Great Britain based on data collected by a task group of the British Thoracic Society. Of 153 reported deaths, 90 were related directly to asthma. Fifty-five of these deaths were observed at autopsy, and the classic findings in deaths from asthma were described. In their review, the task group of the British Thoracic Society believed that 72 of the 90 deaths directly related to asthma were avoidable. Most of these deaths occurred outside the hospital. This task group has recommended increased patient and physician recognition of the presence of asthma and increased drug therapy, including inhaled bronchodilators. They have also recommended improved supervision and education of the patient, expanded prophylactic treatment, improved self-management, and improved emergency treatment of the patient with asthma in status. In the British study, delay in obtaining care and recognizing the severity of the disease stage were considered to be major factors associated with death from asthma. It is of interest that the death rate from asthma in the United Kingdom is considerably higher than that in the United States. Although there was a parallel between the over-the-counter sales of metered-dose inhalers in the United Kingdom and deaths from asthma during the epidemic of the 196Os, the British Thoracic Society study of deaths from asthma did not confirm a clear association between the use of inhaled p-agonists and death from asthma. Also discussed at the Fogarty International Workshop on the etiology of asthma and presented to the American Academy of Allergy and Immunology in March 1985, are data from the National Hospital Discharge Survey that indicate by sampling an estimate of the number of hospital discharges as well as the primary diagnosis.6 Hospital discharges with the primary diagnosis of asthma between the years I %5 and 1983 were reviewed. Hospitalizations for asthma in all age groups increased from 127,000 in 1965 to 459,000 (289,009 corrected for the ICD change) in

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Increases in mortality

1983. Approximately 25% of these discharges occurred among children less than 15 years of age. Among children, the discharge rate per 100,000 per year increased from 48 in 1965 to 263 in 1983. During the same period, the rate increased in adults (15 years and older) from 74 to 179 (112 if adjusted for the ICD change) per 100,000 per year. The data reflect that in the United States today there is a mild increase in the prevalence of asthma, a definite increase in mortality from asthma, and a very marked increase in hospitalization for asthma. The reasons for these events are far from being understood.

from asthma

2. Evans R, Mullally DI, Wilson RW, Gergen PJ. Rosenberg HM, Grauman JS, Edmonds FC, Fbinleil M. National trends in the morbidity and mortality of asthma in the U.S.A. Chest (in press). 3. Markham D, Chang M, Evans R, MuIlally D. Epidemiologic study of deaths from asthma among children in U.S. 19651983 [Abstract]. J ALLERGY CLJNIMMIJNOL1986;77:161. 4. Paulozzi W, Coleman JJ, Buist AS. A recent increase in asthma mortality in the Northwestern United States. Ann Allergy 1986;56:392. 5. Stableforth DE. Asthma deaths in the United Kingdom: international symposium on status asthmaticus and asthma deaths. Providence, R.I.: Brown University, 1985. 6. Mullally DI, Grauman JS, Evans R, Kaslow A. Hospitahzations of children for asthma in U.S.A. 19651982 [Abstract]. J ALLERGY CLIN IMMUNOL 1985;75:197.

REFERENCES 1. Sly RM. Increases in deaths from asthma. Ann Allergy 1984;53:20.

Asthma mortality: P. G. J. Burney,

M.B., M.F.C.M.

England and Wates Baltimore, Md.

Since the major epidemic of asthma deaths in the United Kingdom in the 1960s and its resolution, there has been a further, more gradual increase in reported asthma mortality. ’ As in the previous epidemic, the increase is more pronounced in the 5- to 34-year-old age group; it also appears to be more pronounced in males than in females. Between 1974 and 1984, the mortality rate among 5- to 34-year-old individuals has risen from 5.3 per million population to 10.5 per million, an increase that represents a rise of 4.7% per annum (p < 0.05) after taking account of the artifactual increase caused by changes in the coding of cause of death in 1979. There was estimated to be an increase of 6.1% per annum (p < 0.05) among males and 2.8% per annum among females (p > 0.05). Asthma mortality in England and Wales is also characterized by wide geographic variation. Charlton et al.’ have demonstrated a sixfold variation in standardized mor-

From the Department of Epidemiology, School of Hygiene and Public Health, The Johns Hopkins University, Baltimore, Md. Reprint requests: Peter Burney, M.B., M.F.C.M., Department of Epidemiology, Johns Hopkins University School of Hygiene, 6 17 North Wolfe St., Baltimore, MD 21205.

tality ratios for 5- to 44-year-old individuals living in different Area Health Authorities, and this variation is far more than would be expected by chance. The recent increase in mortality is unlikely to be due to random variation because it is fairly consistent during a IO-year period, statistically significant, and found in a number of other countries, including the United States. The increase could, however, be due to a change in the way that doctors are certifying cause of death. There is inadequate information on which to make any authoritative statement, but the balance of evidence must still favor a real change in asthma mortality. Deaths from bronchopneumonia have been declining over this period. If the increase in deaths from asthma was due to diagnostic transfer, this might be the most plausible source of the additional deaths. There is, however, no need to explain away the decline in reported deaths from bronchopneumonia in terms of reclassification as asthma. It is quite plausible that deaths from this cause have been declining and, although the attribution of deaths to bronchopneumonia is notably unreliable, this is not due to confusion with deaths from asthma. In an older age group than the 5- to 34-year-old subjects discussed in this article, Heasman and Lipworth reported on 385 subjects 379