Accelerated infant growth increases childhood asthma risk
MedWire News: Results from a Dutch study suggest that accelerated growth in infancy is associated with an increased risk for childhood asthma.
Writing in the American Journal of Respiratory and Critical Care Medicine, Liesbeth Duijts (Erasmus MC, Rotterdam) and colleagues explain that low birthweight is known to be "associated with an increased risk of wheezing in childhood."
But they add that little is known about the effects of fetal and infant growth patterns on childhood asthma risk.
To investigate, the team analyzed data on 5125 children who participated in the Generation R Study, a population-based prospective cohort study of pregnant women and their children in Rotterdam.
Fetal growth characteristics (head circumference, femur length, abdominal circumference, and weight) during the second and third trimesters were assessed using ultrasound scans, and infant growth (head circumference, length, and weight) was assessed at birth and at the ages of 3, 6, and 12 months.
Information on asthma symptoms was obtained using parental questionnaires at the ages of 1, 2, 3, and 4 years.
After accounting for factors such as gender, a family history of asthma and allergies, parental smoking, and parity, the researchers found that fetal growth patterns were not associated with asthma symptoms at the age of 4 years.
However, accelerated weight gain (>0.67 change in standard deviation score) between birth and the age of 3 months was significantly associated with an increased risk for asthma symptoms, including wheezing (odds ratio [OR]=1.44), shortness of breath (OR=1.32), dry cough (OR=1.16), and persistent phlegm (OR=1.30), at the age of 4 years.
The researchers note that the association between accelerated infant growth and the risk for asthma symptoms at 4 years of age was stronger in children with atopic than nonatopic mothers.
Duijts and team conclude: "Our results suggest that not fetal growth, but accelerated growth in the first 3 months of life is associated with an increased risk of asthma symptoms during the first 4 years of life."
They add: "Further studies are needed to replicate these findings and to explore underlying mechanisms of the effect of growth accelerationon respiratory health, in particular on the various phenotypes of asthma in later life."
By Mark Cowen