Weight does not have lasting impact on childhood asthma-like symptoms

MedWire News: Overweight children are at an increased risk of suffering from asthma-like symptoms such as shortness of breath and increased airway sensitivity at the age of 8 years, research shows.

However, a higher body mass index at an earlier age does not increase this risk if the child's weight returns to normal by the ages of 6 or 7 years.

Accumulating evidence indicates that overweight children are more likely to have asthma than their normal-weight peers, explain Dr Salome Scholtens (Utrecht University, The Netherlands) and colleagues.

They add that a number of studies have also shown that children with an initially high body mass index are more likely to subsequently develop asthma over a follow-up period than those with an initially normal body mass index.

To determine if children who are overweight early in life are still at an increased risk of developing asthma if they return to a healthy weight during childhood, the researchers studied data on 3756 children who were monitored from birth until the age of 8 years.

Analysis revealed that children with a persistently elevated body mass index during childhood or a high body mass index at the ages of 6 and 7 years had a 68% greater relative risk of suffering from shortness of breath (dyspnea) at 8 years of age than those with a consistently normal weight.

Similarly, children who were persistently overweight during childhood or at 6 and 7 years of age had a 66% greater risk of airway sensitivity (bronchial hyper-responsiveness) at the age of 8 years than those with a normal body mass index.

However, children with a high body mass index at a young age, but who returned to a normal body mass index at 6 to 7 years, did not have greater risk of shortness of breath and airway sensitivity at the age of 8 years than those with a consistently normal weight.

Dr Scholtens and team conclude in the Journal of Allergy and Clinical Immunology: “A high body mass index earlier in life is not associated with asthma symptoms and bronchial hyper-responsiveness if the child develops a body mass index within the normal range.

They add: “These results suggest that the development of a normal weight may positively affect asthma in overweight children.”