Prevalence of atopy, asthma symptoms and diagnosis, and the management of asthma: comparison of an affluent and a non-affluent country
- aInstitute of Respiratory Medicine, University of Sydney Department of Medicine, PO Box M77, Camperdown, NSW 2050, Australia, bClinical Epidemiology Unit, University of Sydney Department of Pediatrics and Child Health, New Children’s Hospital, Westmead, NSW 2145, Australia
- Dr A O Faniran.
- Received 8 June 1998
- Revision requested 20 August 1998
- Revised 15 March 1999
- Accepted 17 March 1999
Abstract
BACKGROUND The prevalence of childhood asthma and of atopy varies widely between countries. However, few studies have compared the pattern of diagnosis and management of asthma, or the role of atopy in predisposing to asthma between a less affluent country and a more affluent country. The aim of this study was to compare the prevalence of symptoms, diagnosis, and management of asthma, and the prevalence of atopy as measured by skin prick tests in Nigeria and Australia using a standardised methodology.
METHODS Respiratory history was collected using a validated questionnaire administered to parents, and atopy was measured with skin prick tests in 654 Australian and 566 Nigerian children aged 8–11 years (70% consent rate in Australia, 60% in Nigeria).
RESULTS Wheeze and persistent cough were less prevalent in Nigeria (10.2% and 5.1%, respectively) than in Australia (21.9% and 9.6%, respectively), caused less morbidity, and were less likely to be labelled or treated as asthma than in Australia. There was no significant difference in the overall prevalence of atopy between the two countries (Australia 32.5%, Nigeria 28.2%). Atopy was a strong risk for wheeze in both countries (odds ratio (OR) 3.4 (95% CI 2.3 to 5.1) in Australia, 1.8 (95% CI 1.0 to 3.3) in Nigeria), especially atopy to house dust mites (OR 3.1 (95% CI 2.1 to 4.7) in Australia, 2.4 (95% CI 1.3 to 4.3) in Nigeria).
CONCLUSION Although there was a similar prevalence of atopy in both countries, Australian children had a higher prevalence of asthma symptoms. Further studies are needed to determine why atopic children in Australia are more at risk of developing asthma. Such studies will have important implications for the prevention of asthma.
