Increased airway resistance in early childhood linked to asthma

The first 3 years of life are critical to the loss of lung function associated with asthma, according to research presented at the 2014 European Academy of Allergy and Clinical Immunology annual congress in Copenhagen, Denmark.

Klaus Bønnelykke, PhD, of the University of Copenhagen and Danish Pediatric Asthma Center, and colleagues assessed 411 children considered at-risk for asthma. Airway resistance was measured by whole-body plethysmography every 6 months from ages 3 to 7 years. Neonatal spirometry was measured when study participants were aged 4 weeks. Asthma and atopic dermatitis were determined from daily diaries, clinical visits every 6 months and acute visits. Sensitization was assessed when participants were aged 6 months, 18 months, 4 years and 6 years. Nicotine levels in participants’ hair were measured at 3 years, which determined their exposure to tobacco smoke.

Klaus Bønnelykke

Male gender, nicotine level in hair, ORMDL3 and FLG gene variants, were associated with increased airway resistance. Neonatal airflow was inversely related to airway resistance. Children with asthma by age 7 years had significantly increased airway resistance when aged 3 years, with no further progression. No significant associations were found between airway resistance and sensitization or atopic dermatitis.

“Children with asthma by age 7 had developed increased airway resistance before 3 years of age independent of neonatal lung function. This suggests that the first 3 years of life are critical to the loss of lung function associated with asthma,” the researchers concluded.

For more information:

Bønnelykke K. Abstract #303. Presented at: European Academy of Allergy and Clinical Immunology annual congress 2014; June 7-11, 2014; Copenhagen, Denmark

Disclosure: Infectious Diseases in Children was unable to confirm relevant financial disclosures.