Around 7% of children and adolescents living in Catalonia have asthma. Until puberty, the disease affects boys more than girls, but this trend reverses afterwards. Diagnoses are also more frequent among people living in areas with a lower socioeconomic level. These are the main findings of a cohort study coordinated by researchers from IDIAPJGol, recently published in the journal Thorax. The study follows people aged between 1 and 17 who were diagnosed with asthma between 2010 and 2024. It is the largest epidemiological study carried out in Catalonia on the evolution of the disease.
The research analyses electronic health records of more than two million individuals aged between 1 and 17 collected through the Information System for Research in Primary Care (SIDIAP), which includes anonymised data from the medical records of 75% of the Catalan population. The research team complemented this information with hospital discharge records from the public hospital network in Catalonia, through the public Health Data Analytics Programme for Research and Innovation (PADRIS).
The study results show that the incidence of asthma – that is, the number of new diagnoses – during the study period was 687.46 cases per 100,000 person-years, a figure that was higher among younger children, preadolescent boys and people living in areas with a lower socioeconomic level. Specifically, incidence was more than three times higher among children aged 1 to 4 than among adolescents aged 15 to 17.
More cases than before the pandemic
The analysis of temporal trends shows that asthma incidence decreased before the COVID-19 pandemic and fell sharply in 2020, although the authors caution that this decline could have been related to difficulties accessing healthcare services during the crisis. That year, 423.29 cases per 100,000 person-years were recorded, compared with 667.28 cases in 2019. Subsequently, the number of cases increased again, particularly among children aged 5 to 14. By 2024, annual incidence had reached 824.09 cases per 100,000 person-years, above the levels recorded immediately before the pandemic.
More boys than girls
The study identifies differences in asthma incidence according to sex. Over the study period, the risk of receiving a first diagnosis was 35% higher among boys than among girls. This difference was maintained across all age groups except for those aged 15 to 17, among whom incidence was higher in girls.
Regarding socioeconomic inequalities, the study shows that children living in areas with greater socioeconomic deprivation had an asthma incidence 14% higher than that of children living in areas with the least deprivation.
IDIAPJGol researcher Talita Duarte-Sallés, who coordinated the study, highlights that “the results underscore the importance of monitoring the incidence and prevalence of the disease in our setting in order to develop prevention policies, particularly in socioeconomically vulnerable areas”.
Article reference
Palomar-Cros A, Abellan A, Raventós B, Pistillo A, Reyes C, Guiliodori A, Granés L, García Rivero JL, Verhamme KM, Roel E, Duarte-Salles T. Trends in asthma incidence and prevalence in 2 million children and adolescents in Catalonia, Spain, 2010-2024: a population-based cohort study. Thorax. 2026 Jun 8:thorax-2026-224985. doi: 10.1136/thorax-2026-224985. Epub ahead of print. PMID: 42259635.
