RESUMEN
BACKGROUND: The Global Asthma Network (GAN) builds on the International Study of Asthma and Allergies in Childhood (ISAAC). OBJECTIVE: To compare asthma prevalence time trends in primary and secondary school children in four Mexican centers participating in ISAAC and GAN. METHODS: GAN is a cross-sectional, multicenter, epidemiological methodology carried out in groups of primary school children aged 6-7 and adolescents aged 13-14 following the ISAAC Phase Three protocol, with additional questions on risk factors and asthma management. RESULTS: Overall, the prevalence of asthma symptoms and diagnosis in primary school children was higher in males than in females both in ISAAC (p < 0.05) and in GAN (p < 0.01), while adolescent females had a higher prevalence, also both in ISAAC (p < 0.001) and in GAN (p < 0.001). CONCLUSION: The prevalence of asthma and its symptoms has increased from ISAAC Phase Three since 2003 to GAN Phase I in Mexico in 2019. These findings are in line with the increases observed in the centers with low asthma baseline prevalence in ISAAC Phase One in comparison with ISAAC Phase Three.
Asunto(s)
Asma/epidemiología , Adolescente , Asma/diagnóstico , Niño , Estudios Transversales , Femenino , Humanos , Masculino , México/epidemiología , Prevalencia , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
BACKGROUND: Eczema is a common chronic disease which has significant morbidity and costs for children and their families. Phase One (1993) of the International Study of Asthma and Allergies in Childhood (ISAAC) found a high prevalence of symptoms of eczema in New Zealand. OBJECTIVE: In Phase Three (2001-3) we aimed to answer these three questions: Is the prevalence of eczema changing over time?; Are there ethnic differences in prevalence?; and What are the risk factors for eczema? METHODS: Five New Zealand centres participated in ISAAC Phases One and Three using the same methodology. Questionnaires about ethnicity, symptoms of eczema and environmental factors were completed by parents of 6-7 year olds (children) and self-completed by 13-14 year olds (adolescents). Prevalence and change per year were calculated by centre, ethnicity and gender. Prevalence differences between centres and associations with environmental factors were examined using logistic regression. RESULTS: There was little change in prevalence over time for the children, and a decrease in prevalence for the adolescents. Prevalence was higher among Māori and even higher among Pacific participants than among European children. Positive associations with current eczema symptoms were found for both age groups for truck traffic in the street of residence, and current paracetamol consumption, and for children only, antibiotics or paracetamol in the 1st year of life. Inverse associations were found with residence in New Zealand less than 5 years, consumption of milk, seafood, and eggs, and presence of a dog in the home. CONCLUSION: Eczema remains a significant problem, particularly for young Māori and Pacific New Zealanders in whom less recognition of eczema and poorer access to effective, sustained eczema management may be contributing factors. Reverse causation may explain all the environmental findings apart from truck traffic which is increasing in New Zealand.