The asthma risk among young children is not correlated with low birth weight, a new study has concluded.
In the study, allergists evaluated the medical records of about 4,000 children born between January 1, 1976, and December 31, 1979 in Rochester, Minnesota. Of those, 193 were classified as having low birth weight. Of that cohort, only 13 (6.7 percent) developed asthma. Of the normal weight group, about five percent were diagnosed with asthma.
Lead study author Hyeon Yang, M.D. addressed the implications of the study according to Medical News Today:
"Asthma is the most common chronic illness in childhood and is a leading reason for missed school days. While environment, genetics, and their interaction are thought to increase one's risk of developing asthma, we now should not assume that low birth weight is associated with asthma. This is an important finding as we continue to understand who is at risk for asthma and why."Low birth weight is generally defined as less than 5.5 pounds.
The study published in the January issue of Annals of Allergy, Asthma and Immunologypublished by the American College of Allergy, Asthma and Immunology concluded that "birth weight is not associated with risk of asthma during the first 6 years of life."
The medical community has yet to definitively determine what causes asthma, but obesity (but not birth weight according to this study) is apparently a risk factor. The condition is more common in children than adults and in boys rather than girls. About 30 million Americans and 300 million people around the world have been estimated to have asthma symptoms.