"Previous research on the relationship between neonatal lung function and the development of asthma has been conflicting," said Doctor Hans Bisgaard of the University of Copenhagen. "Our study shows that children with asthma by age seven already had significant airflow deficits and increased bronchial responsiveness as neonates. Lung function deficits also progressed throughout childhood in our study, suggesting a potential opportunity for early intervention."
The prospective study enrolled a birth cohort of 411 at-risk children of asthmatic mothers. Spirometry was performed at one month in 403 (98 per cent) children and again at age seven in 317 (77 per cent).
Significant neonatal airflow deficits, as measured by forced expiratory flow at 50 per cent of vital capacity and forced expiratory volume after 0.5 seconds, were observed among the 14 per cent of children who developed asthma by age seven. Bronchial responsiveness to methacholine, which provokes narrowing of the airways, was also significantly associated with the development of asthma. Neonatal airway reactivity was a stronger predictor of asthma than neonatal lung function.
"We found that approximately 40 per cent of the airflow deficit that was associated with asthma in our study was present at birth, while 60 per cent developed through early childhood along with the disease," says Bisgaard. "This indicates that both prenatal and early childhood mechanisms are potential intervention targets for the prevention of asthma."
The study used a homogenous study sample, which might limit extrapolation of the results to other populations. "It seems that lung function changes associated with asthma occur very early in life and maybe even before birth," concluded Bisgaard. "This may explain the lack of effect from early intervention with inhaled corticosteroids and should direct research into the pathogenesis and prevention of asthma towards the earliest phases of life."
MEDICA.de; Source: American Thoratic Society