(Questionnaire study of effect of sex and age on the prevalence of wheeze and asthma in adolescence)
In early childhood wheezing and asthma are more common in boys than girls. This difference has either disappeared or reversed by early adulthood. In this week's BMJ, Andrea Venn et al from the City Hospital in Nottingham report the findings of their study of nearly 30,000 (27,826) children aged 11-16 years (51 per cent of whom were boys) in the Nottingham area.
The authors found that there is a gender reversal around the time of puberty, due to both an increase in reported wheeze in girls and a decrease in boys. Venn et al conclude that, based on evidence from previous studies, there may be a hormonal influence and advocate further research in this area.
Among the alternative explanations given, girls may experience different exposures to the things which trigger wheezing, such as smoking, and boys may have a relatively greater increase in airway size at this age.
Contact:
Andrea Venn, Medical Statistician, Division of Respiratory Medicine, City Hospital, Nottingham Andrea.Venn@nottingham.ac.uk