RT Journal Article
SR Electronic
T1 Asthma in South African adolescents: a time trend and risk factor analysis over two decades
JF ERJ Open Research
JO erjor
FD European Respiratory Society
SP 00576-2020
DO 10.1183/23120541.00576-2020
A1 C.B. Baard
A1 Z. Franckling-Smith
A1 J. Munro
A1 L. Workman
A1 H.J. Zar
YR 2020
UL http://openres.ersjournals.com/content/early/2020/11/06/23120541.00576-2020.abstract
AB Background South Africa has undergone major economic and health system changes impacting the epidemiology of childhood asthma. This study aimed to investigate prevalence time-trends of asthma in South African adolescents over 2 decades and to identify associated risk-factors.Methods A cross-sectional survey was conducted in 2017, in a randomised sample of 13–14 year-old Cape Town adolescents, using the standardised Global Asthma Network written, video, and environmental questionnaires. Using time-trend analysis, the prevalence and severity of asthma were compared with data from the 2002 ISAAC phase III study. Environmental and social risk-factors were analysed.Results 3979 adolescents were included. Prevalence of lifetime and current asthma were 34.5% and 21.3%, respectively, on the self-report written questionnaire, similar to 2002 results. The prevalence of severe asthma in the last 12 months increased, measured by wheeze limiting speech (7.8% to 11.8%), ≥4 attacks of wheezing (5.0% to 5.8%) or ≥1 night·week−1 waking from wheezing (5.0% to 6.9%). The video questionnaire revealed increases in lifetime (16.9% to 22.5%), current (11.2% to 18.7%), or severe asthma (12.1% to 14.8%). Multivariate analysis showed associations between current asthma and smoking, female sex, pet exposure or higher socioeconomic status. Severe asthma was associated with smoking, pet exposure, outdoor pollution exposure or informal housing. 33% of those with severe or current asthma had been diagnosed.Conclusion The prevalence of asthma is high, with increasing rates of severe asthma in adolescents. Underdiagnosis is a major concern and reduction in exposure to environmental factors, particularly smoking, and improved socioeconomic development are needed.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Mrs Baard reports grants from South African Medical Research Council, and a grant from Allergy Society of South Africa, during the conduct of the study.Conflict of interest: Dr. Franckling-Smith reports grants from South African Medical Research Council, grants from Allergy Society of South Africa, during the conduct of the study.Conflict of interest: Dr. Munro reports grants from South African Medical Research Council, grants from Allergy Society of South Africa, during the conduct of the study.Conflict of interest: Dr. Workman reports grants from South African Medical Research Council, grants from Allergy Society of South Africa, during the conduct of the study.Conflict of interest: Dr. Zar reports grants from South African Medical Research Council, grants from Allergy Society of South Africa, during the conduct of the study.