Children who are overweight at age 6 to 7 years are at increased risk for having symptoms of asthma like shortness of breath and "twitchy" airways when they are 8 years old, results of a study conducted in the Netherlands show.
However, children who are overweight at a younger age but reach a normal weight by age 6 to 7 do not appear to have an increased risk for asthma symptoms, according to the study.
"These findings suggest that being overweight may affect a child's development of asthma symptoms," Dr. Salome Scholtens from the National Institute for Public Health and the Environment in Bilthoven told Reuters Health.
"However, if a previously overweight child develops a normal weight, then the asthma symptoms are less likely to persist. We propose that development of a normal weight might positively affect asthma symptoms in overweight children," Scholtens added.
Each year until the age of 8, Scholtens and colleagues had the parents of 3756 children report their children's weight and any episodes of wheezing or other breathing difficulties as well as the use of inhaled steroids. The researchers tested the children to see how sensitive their airways were to various inhaled allergens.
When the children were 8 years old, 275 (7.3 percent) wheezed, 361 (9.6 percent) had difficulty breathing and 268 (7.1 percent) had a prescription for an inhaled steroid in the preceding year.
According to the investigators, children who were persistently heavy from a very young age and between age 6 to 7 years were 68 percent more likely to have breathing difficulties and 66 percent more likely to have twitchy airways at age 8 than children who were leaner in childhood.
As mentioned, children who were heavier at a very young age, but who developed a normal weight at age 6 to 7 did not have an increased risk of breathing difficulties.
These findings suggest that being overweight in early childhood does not have a lasting effect on breathing difficulties if the child develops a normal weight by 8 years old.
The writers of a commentary published with the study in the Journal of Allergy and Clinical Immunology call the findings "encouraging."