This paper is only available as a PDF. To read, Please Download here.
Abstract
Only limited data are available about the incidence of asthma based on longitudinal prospective studies. Further, the results from different studies on incidence vary considerably depending on the age composition of the cohorts under study, the used methods and the criteria for disease. Also among adults high incidence rates have been reported during recent years. The aim of this study was to examine to what extent the incidence of physician-diagnosed asthma could be explained by a real incidence of the disease, and to what extend by an increased diagnostic activity or altered diagnostic praxis. Another aim was to study risk factors for asthma based on incident cases. Three cross-sectional surveys have been performed in the same population sample living in the northern-most province of Sweden, Norrbotten. The first survey was performed in 1986, and 5698 subjects, 86% of those invited, responded to a postal questionnaire. Of these, 4754 subjects (83%) participated at the third survey in 1996. After exclusion of all subjects who had reported that they had asthma in 1986, or had been classified as having asthma in 1986, 68 men and 98 women (P=0·02) reported in 1996 that they had been diagnosed as having asthma by a physician. Thus, the cumulative incidence for the 10-year period was 3·2% among men and 4·5% among women. After correction for subjects who already in 1986 had reported symptoms common in asthma, or had been classified as having chronic bronchitis, 97 subjects with incident asthma remained, which corresponded to an annual incidence rate among men of 1·7 and among women of 2·9/1000 persons year−1(P=0·01). Clinical examinations confirmed asthma in a large majority of these 97 subjects. Significant risk factors were family history of asthma, both ex- and current smoking, and female sex. The socio-economic groups manual workers and assistant non-manual employees were associated with incident asthma, although not significantly. The increasing prevalence of asthma among adults during recent 10–20 years may to a considerable extent be explained by an increased diagnostic activity or altered diagnostic praxis. Use of different methods when measuring incidence may in part explain the extremely diverging incidence rates of asthma found in different studies.
Keywords
References
REFERENCES
- Asthma from birth to age 23; incidence and relation to prior and concurrent atopic disease.Thorax. 1992; 47: 537-542
- Epidemiology of asthma and allergic rhinitis in a total community, Tecumseh, Michigan.J Allergy Clin Immunol. 1974; 54: 100-110
- The prevalence and incidence of asthma and asthma-like symptoms in a general population sample.Am Rev Respir Dis. 1980; 122: 567-575
- Incidence of asthma in Swedish teenagers: relation to sex and smoking habits.Thorax. 1995; 50: 260-264
- Prevalence and incidence of asthma and rhinoconjunctivitis in Swedish teenagers.Allergy. 1998; 53: 28-35
- Incidence and prognosis of asthma and wheezing illness from early childhood to age 33 in a national British cohort.BMJ. 1996; 312: 1195-1199
- Occurrence, predictors, and consequences of adult asthma in NHANESI and follow-up survey.Am Rev Respir Dis. 1989; 139: 721-724
- Predictors of the new onset of wheezing among middle-aged and older men.Am Rev Respir Dis. 1993; 147: 367-371
- Obstructive lung disease in northern Sweden: respiratory symptoms assessed in a postal survey.Eur Respir J. 1991; 4: 257-266
- Incidence of asthma in adults—report from the Obstructive Lung Disease in Northern Sweden study.Allergy. 1997; 52: 1071-1078
- An interview Study to estimate prevalence of asthma and chronic bronchitis—The Obstructive Lung Disease in Northern Sweden Study.Eur J Epidemiol. 1993; 9: 123-133
- Methacholine reactivity and asthma. Report from the Northern Sweden Obstructive Lung Disease Study.Allergy. 1993; 48: 117-124
- Prevalence of bronchial asthma and chronic bronchitis in an industrial community in northern Sweden.Scand J Soc Med. 1982; 10: 11-16
- BMJ. 1960; ii: 1665
- Prevalence of obstructive lung diseases and respiratory symptoms in southern Sweden.Respir Med. 1998; 92: 1337-1345
- Increasing prevalence of asthma but not chronic bronchitis in Finland? Report from the FinEsS-Helsinki study.Respir Med. 1999; 93: 798-809
- Reproducibility and comparison of response to inhaled histamine and methacholine.Thorax. 1978; 33: 705-710
- Thorax. 1997; 52: S5
- Adult patients may outgrow their asthma. A 25-year follow-up study.Am J Respir Crit Care Med. 1997; 1551: 1267-1272
- Remission of asthma in the middle aged and elderly: report from the Obstructive Lung Disease in Northern Sweden Study.Thorax. 1999; 54: 611-613
Statistics Sweden, The Socio-economic Classification of Occupations, 1982
- Epidemiologic approaches for the identification of asthma.Chest. 1987; 91S: 74-78
- Asthma and asthma-like symptoms in adults assessed by questionnaires. A literature review.Chest. 1993; 104: 600-608
- Findings before diagnoses of asthma among the elderly in a longitudinal study of a general population sample.J Allergy Clin Immunol. 1991; 88: 870-877
- Does measurements of bronchial hyperreactivity help in the clinical diagnosis of asthma.Eur J Respir Dis. 1986; 68: 233-238
- Asthma, asthma-like symptoms, chronic bronchitis, and the degree of bronchial hyper-responsiveness in epidemiologic surveys.Am Rev Respir Dis. 1987; 136: 613-617
- A community based study of the epidemiology of asthma. Incidence rates, 1964–1983.Am Rev Respir Dis. 1992; 146: 888-894
- Incidence of occupational asthma and persistent asthma in young adults has increased in Finland.Chest. 1996; 110: 58-61
- Incidence and prevalence of physician-diagnosed asthma in a suburban population of young adults.Ann Allergy Asthma Immunol. 1996; 77: 304-308
- Epidemiology of asthma in Denmark.Chest. 1987; 91S: 107-114
- Cigarette smoking and incidence of chronic bronchitis and asthma in women.Chest. 1995; 108: 1557-1561
- A prospective study of asthma in a rural community.Chest. 1984; 85: 623-630
- Prospective study of asthma in relation to smoking habits among 14 729 adults.Thorax. 1988; 43: 534-539
- Incidence rate of adult-onset asthma in relation to age, sex, atopy and smoking. A Swedish popula- tion-based study of 15 813 adults.Int J Tuberc Lung Dis. 1999; 3: 192-197
- Childhood asthma in four regions in Scandinavia: risk factors and avoidance effects.Int J Epidemiol. 1997; 26: 610-619
- Prevalence of allergic diseases in schoolchildren in relation to family history, upper respiratory infections, and residential characteristics.Allergy. 1996; 51: 232-237
- Smoking habits and changes in smoking habits as they relate to chronic conditions and respiratory symptoms.Am J Epidemiol. 1977; 105: 534-543
- An epidemiologic study of bronchial asthma and smoking.Epidemiology. 1995; 6: 503-505
- Smoking, socio-economic status, and chronic respiratory diseases.Am Rev Respir Dis. 1977; 116: 403-410
Article info
Publication history
Received:
May 4,
2001
Identification
Copyright
© 2001 Harcourt Publishers Ltd. Published by Elsevier Inc.
User license
Elsevier user license | How you can reuse 
Elsevier's open access license policy
Elsevier user license
Permitted
For non-commercial purposes:
- Read, print & download
- Text & data mine
- Translate the article
Not Permitted
- Reuse portions or extracts from the article in other works
- Redistribute or republish the final article
- Sell or re-use for commercial purposes
Elsevier's open access license policy
