Asthma prevalence in adults and children
Asthma prevalence seems to be still increasing as suggested by Borna et
al., who investigated its change between 2008 and 2016 in Sweden. The
authors observed a significant rise of reported frequencies of ever
asthma, physician‐diagnosed asthma, use of asthma medication and current
asthma, especially in young adults aged 16‐25 years.9At the same time, an increase in the prevalence of respiratory symptoms
during the same period was reported, suggesting the possibility that
actually, asthma is underdiagnosed. The potential risk factors for
asthma remained the same during the study period.9
Recent studies assessed the prevalence of asthma in preschoolers (4.4
%) and elementary school children (6.4%) according to Global
Initiative for Asthma (GINA) definition.8 While no
significant difference between rural and urban children was observed,
Branco et al. found an association with previously identified risk
factors for asthma development, including parental asthma and
antibiotics treatment in the first year of life.10 Liu
et al. investigated the link between maternal hypothyroidism in the
perinatal period and childhood asthma risk, in a population‐based cohort
study using Danish national registers. A higher incidence of asthma was
found compared to children born to mothers with no thyroid dysfunction.
The risk was even higher if the mothers did not receive thyroid hormone
treatment during pregnancy.11