Prevalence of asthma, rhinitis and eczema among children in 2 Canadian cities: the International Study of Asthma and Allergies in Childhood.

BACKGROUND Wide variations in the prevalence of asthma, rhinitis and eczema have been reported between regions within Canada and between different countries. The International Study of Asthma and Allergies in Childhood (ISAAC) was developed to provide a standardized tool and methodology to ascertain the prevalence of asthma and allergies in different regions. Comparisons of prevalence rates across geographic regions and at different times may help to identify factors that contribute to the development of these conditions in individuals. METHODS Two Canadian centres, Hamilton and Saskatoon, participated in the ISAAC. A standard questionnaire was distributed through schools and completed by 13- and 14-year-old children and by the parents of 6- and 7-year-old children. Prevalence rates and 95% confidence intervals were calculated for asthma, wheezing, rhinitis and eczema. RESULTS The overall response rates were 75.1% among the children 6 and 7 years old and 68.6% among those 13 and 14 years old. Among the younger children, the lifetime prevalence of asthma was 17.2% in Hamilton and 11.2% in Saskatoon; the corresponding rates among the older children were 19.2% and 12.2% respectively. The prevalence of wheezing in the 12 months before the survey in the younger group was 20.1% in Hamilton and 14.1% in Saskatoon; in the older group it was 30.6% and 24.0% respectively. The prevalence of rhinitis in the 12 months before the survey was 28.6% in Hamilton and 22.6% in Saskatoon in the younger group and 45.8% and 33.8% respectively in the older group. The prevalence of eczema was slightly higher in Saskatoon in both age groups. INTERPRETATION High prevalence rates of asthma, rhinitis and eczema exist among school children in Hamilton and Saskatoon, similar to rates in other Western countries. Further studies are required to determine the factors associated with the high rates in the 2 regions and possible reasons for the higher rates in Hamilton.

[1]  Ennis,et al.  THE ROLE OF COCKROACH ALLERGY AND EXPOSURE TO COCKROACH ALLERGEN IN CAUSING MORBIDITY AMONG INNER-CITY CHILDREN WITH ASTHMA , 2000 .

[2]  Richard Beasley,et al.  Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC , 1998, The Lancet.

[3]  C. -. Yang,et al.  Damp housing conditions and respiratory symptoms in primary school children , 1997, Pediatric pulmonology.

[4]  V. Nelen,et al.  Higher asthma occurrence in an urban than a suburban area: role of house dust mite skin allergy. , 1997, The European respiratory journal.

[5]  D. Strachan,et al.  The home environment and asthma symptoms in childhood: two population based case-control studies 13 years apart. , 1997, Thorax.

[6]  T. Platts-Mills,et al.  Asthma and indoor exposure to allergens. , 1997, The New England journal of medicine.

[7]  I. D. Johnston,et al.  Childhood antecedents of allergic sensitization in young British adults. , 1997, The Journal of allergy and clinical immunology.

[8]  J. Carlin,et al.  Validation of questionnaire and bronchial hyperresponsiveness against respiratory physician assessment in the diagnosis of asthma. , 1996, International journal of epidemiology.

[9]  Y. Lau,et al.  Prevalence of and factors associated with childhood asthma in Hong Kong , 1995, Acta paediatrica.

[10]  D. Strachan,et al.  International Study of Asthma and Allergies in Childhood (ISAAC): rationale and methods. , 1995, The European respiratory journal.

[11]  J. Hogg,et al.  Asthma Mortality in Canada, 1946 to 1990 , 1995 .

[12]  R. Burnett,et al.  Prevalence of childhood asthma across Canada. , 1994, International journal of epidemiology.

[13]  D. Strachan,et al.  Childhood eczema: disease of the advantaged? , 1994, BMJ.

[14]  M. Burr,et al.  Childhood asthma in four countries: a comparative survey. , 1994, International journal of epidemiology.

[15]  T. Nicolai,et al.  Prevalence of asthma and atopy in two areas of West and East Germany. , 1994, American journal of respiratory and critical care medicine.

[16]  A. Senthilselvan.  Trends and Rural-Urban Differences in Asthma Hospitalizations in Saskatchewan 1970-1989 , 1994 .

[17]  D. Gawkrodger,et al.  The prevalence of childhood atopic eczema in a general population. , 1994, Journal of the American Academy of Dermatology.

[18]  C. Madsen,et al.  Prevalence of atopic disease among Danish school children , 1993, Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology.

[19]  Y. Mao,et al.  Trends in rates of admission to hospital and death from asthma among children and young adults in Canada during the 1980s. , 1993, CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne.

[20]  E. Skobeloff,et al.  The influence of age and sex on asthma admissions. , 1992, JAMA.

[21]  W. Karmaus,et al.  Clinical atopy and associated factors in primary‐school pupils , 1992, Allergy.

[22]  D. Strachan,et al.  Asthma from birth to age 23: incidence and relation to prior and concurrent atopic disease. , 1992, Thorax.

[23]  G. Russell,et al.  Respiratory symptoms and atopy in Aberdeen schoolchildren: evidence from two surveys 25 years apart. , 1992, BMJ.

[24]  B. Brunekreef,et al.  Childhood asthma and the indoor environment. , 1991, Chest.

[25]  Buist As.  Worldwide trends in asthma morbidity and mortality. , 1991 .

[26]  A. Woolcock.  Worldwide trends in asthma morbidity and mortality. Explanation of trends. , 1991, Bulletin of the International Union against Tuberculosis and Lung Disease.

[27]  Eli Warnock.  Has the prevalence of asthma increased in children: Evidence from the national study of health and growth , 1991 .

[28]  A. Buist.  Worldwide trends in asthma morbidity and mortality. , 1991, Bulletin of the International Union against Tuberculosis and Lung Disease.

[29]  P. Gergen,et al.  Changing patterns of asthma hospitalization among children: 1979 to 1987. , 1990, JAMA.

[30]  D. Strachan,et al.  Regional variations in wheezing illness in British children: effect of migration during early childhood. , 1990, Journal of epidemiology and community health.

[31]  R J Rona,et al.  Has the prevalence of asthma increased in children? Evidence from the national study of health and growth 1973-86. , 1990, BMJ.

[32]  D. P. Strachan,et al.  Hay fever, hygiene, and household size. , 1989, BMJ.

[33]  S M Hunt,et al.  Damp housing, mould growth, and symptomatic health state. , 1989, BMJ.

[34]  D. Strachan.  Damp housing and childhood asthma: validation of reporting of symptoms. , 1988, BMJ.

[35]  M. Sears,et al.  International trends in asthma mortality: 1970 to 1985. , 1988, Chest.

[36]  J. Charpin,et al.  Asthma and allergy to house-dust mites in populations living in high altitudes. , 1988, Chest.

[37]  L MacWilliam,et al.  Increased rates of illness and death from asthma in Canada. , 1987, CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne.

[38]  D. Bates,et al.  Asthma mortality and morbidity in Canada. , 1987, The Journal of allergy and clinical immunology.

[39]  T. Peters,et al.  The epidemiology of childhood eczema: II. Statistical analyses to identify independent early predictors. , 1987, Paediatric and perinatal epidemiology.

[40]  E. Mitchell,et al.  Demographic characteristics of asthma admissions to hospitals. , 1986, The New Zealand medical journal.

[41]  D. Strachan.  Wheezing presenting in general practice. , 1985, Archives of disease in childhood.

[42]  E. Mitchell,et al.  International trends in hospital admission rates for asthma. , 1985, Archives of disease in childhood.

[43]  J. Wadsworth,et al.  CHANGES IN THE REPORTED PREVALENCE OF CHILDHOOD ECZEMA SINCE THE 1939-45 WAR , 1984, The Lancet.

[44]  H. Anderson,et al.  Morbidity and school absence caused by asthma and wheezing illness. , 1983, Archives of disease in childhood.

[45]  S. Tonkin,et al.  Asthma prevalence in Tokelauan children in two environments , 1980, Clinical allergy.

[46]  E. Weinberg,et al.  Prevalence of asthma: a comparative study of urban and rural Xhosa children , 1979, Clinical allergy.