Siblings Cut Asthma Risk

Children who have brothers or sisters have a lower asthma risk than children who have no siblings, according to a Canadian study.

The Study

Researchers followed up 170,960 children from birth to age 6. In total, 14.1% of the newborns were seen by a doctor for asthma. The highest incidence of asthma was in the first two years of life.

Results

The study found that children of multiple births and children who had siblings had a lower asthma risk than children who did not have siblings.

Interestingly, children born from July through December had a greater asthma risk than children born from January through March.

The risk of asthma increased if newborns were male, lived in an urban area, were born prematurely, had a low birth weight or their primary-care provider was a pediatrician.

Other risk factors included having a maternal or sibling history of asthma, exposure as an infant to upper- or lower-respiratory tract infections and the presence of congenital conditions, such as respiratory distress syndrome or cystic fibrosis.