Gender difference in allergen exposure link to rhinitis
MedWire News: Exposure to increased levels of house dust mite allergens in the home is associated with an increased risk for rhinitis in girls but not boys, researchers have found.
“Differences between boys and girls in allergic manifestations are well known,” say Randi Jacobsen Bertelsen (Norwegian Institute of Public Health, Oslo, Norway) and colleagues, who add that “this difference is possibly not attributed to physiological differences alone.”
To investigate whether there are gender differences in exposure to allergens at home, and to examine whether this affects risk for rhinitis, the researchers studied data on 437 boys and 360 girls, aged 10 years, who participated in the Environment and Childhood Asthma Study.
Parents were asked to collect dust samples from the children’s mattresses, and these were tested for levels of house dust mite (Dermatophagoides pteronyssinus [Der p 1]), cat (Felis domesticus [Fel d 1]), and dog (Canis familiaris [Can f 1]) allergens.
In total, 190 children had current rhinitis, which was defined by the presence of at least one symptom (runny nose, a blocked nose, or sneezing) in the absence of a cold during the past 12 months.
The researchers found that in all homes, girls had significantly higher mean concentrations of cat and dog allergens in their mattresses than boys, even in households without cats or dogs. For example, in homes without cats, mean Fel d 1 concentrations in mattress dust were 0.74 µg/g for girls and 0.55 µg/g for boys, and in homes without dogs, mean Can f 1 concentrations in mattress dust were 0.37 µg/g for girls and 0.26 ug/g for boys.
There were no differences in Der p 1 concentrations between dust samples for boys’ and girls’ mattresses.
Overall, children with rhinitis were less likely to keep pets and had lower levels of pet allergens in the mattresses than children without rhinitis.
However, the risk for current rhinitis increased 1.2-fold with each 1 µg/g increase in Der p 1 in mattress dust for girls, but there was no such association in boys.
Bertelsen and team conclude in the journal Clinical and Experimental Allergy: “Girls had higher levels of cat and dog allergens in mattress dust compared with boys, a difference that could not be explained by pet ownership alone.
“Increasing Der p 1 levels were found to increase the risk of current rhinitis, but in girls only.”
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By Mark Cowen