Reduced lung function in infants points to chronic asthma in young adults, according to a recent study. The findings suggest that asthma may be caused by abnormal lung development and growth in utero or very early in life.
The study, “Infant lung function predicts asthma persistence and remission in young adults,” was published in the journal Respirology.
“Asthma is a disease of the airways that makes breathing difficult,” Louisa Owens, from the University of Western Australia’s School of Pediatrics and Child Health and the study’s first author, said in a news release. “Inflammation in the air passages results in a temporary narrowing of the airways that carry oxygen to the lungs.”
To assess the association between reduced infant lung function and persistent asthma in young adults, Owens and colleagues examined the clinical records of 253 babies who underwent lung function assessments with maximum expiratory flow at functional residual capacity (V′maxFRC) at 1, 6, and 12 months of age, and again years later when they were 6, 11, 18, and 24 years old.
“While there have been studies involving children and asthma, it’s the first time that we’ve looked at the lung function of infants who have only just been born,” Owens said.
The team found that infants in the lowest quartile of lung function at 1 month were five times more likely to develop asthma as adults (24 years).
“We also looked retrospectively and found that the 24-year-olds we tested who have persistent asthma symptoms had a defect in lung development or growth either in utero or very early in life that persisted as a reduction in lung function as they grew older,” Owens said.
“Our research didn’t extend to the reasons why certain infants are born with a reduced lung function, however there is a variety of factors involved, such as genetics, the mother’s blood pressure, and lifestyle aspects of the parents, among other things,” she said.
Study participants with asthma at 24 years old had persistently lower lung function from infancy with a mean reduction of 16.2 percent in the maximum expiratory flow at functional residual capacity.
The researchers also hoped to discover why some infants with asthma had no symptoms when they grew up. “We wanted to understand why around 30 percent of people who suffer from childhood asthma are free of the illness by the time they reach early adulthood,” Owens said.
They found that symptom-free adults had normal lung function when they were babies. In comparison, those whose asthma persisted into adulthood had reduced lung function when they were infants.
Targeting very early lung development may be crucial in helping eradicate asthma in adults, Owens suggests.