Body Mass can Increase Risk of Asthma during Mid-Childhood
Asthma is a chronic condition that is characterized by inflammation in the airways. The condition is typically diagnosed in young children and can last a lifetime. In a new study, researchers examined potential risk factors of asthma for children. They found that body mass could increase asthma risk during mid-childhood.
For this study headed by Raquel Granell from the University of Bristol, the researchers analyzed 4,835 children who were a part of the Avon Longitudinal Study of Parents and Children (ALSPAC), which was started in 1991. The children were all 7.5-years-old. The researchers examined the effects of genetic variants tied to body mass index (BMI) on asthma risk. They calculated a weighted genetic score using 32 independent BMI-related DNA sequence variations.
The researchers concluded that children's genetic scores could help predict their risk of developing asthma in mid-childhood. Children who had higher levels of body mass and lean mass had a higher risk of asthma. The researchers calculated that for every extra unit of BMI, there was a relative increase in asthma risk by 55 percent. The team concluded that in order to reduce children's risk of asthma, children must be able to maintain normal BMI levels and healthy weights.
"Environmental influences on the development of asthma in childhood have been extensively investigated in epidemiological studies, but few of these provide strong evidence for causality... [higher BMI in mid-childhood] could help explain some of the increase in asthma risk toward the end of the 20th century, although the continued rise in obesity but with a slowing in the rise in asthma prevalence in some countries implies that other non-BMI-related factors are also likely to be important," the authors concluded according to the press release.
The study, "Effects of BMI, Fat Mass, and Lean Mass on Asthma in Childhood: A Mendelian Randomization Study," was published in PLOS Medicine.