Early Asthma, Later Lung Damage?

Nov. 15, 2005 -- The way kids wheeze by age 6 is the way they are likely to wheeze for the rest of their childhoods, a long-term study shows.

Children who wheeze by age 3, the study suggests, may suffer defects in lung function. These changes do not seem to get better -- or worse -- during the school years.

The findings are based on 826 kids followed from birth to age 16 by University of Arizona researcher Wayne J. Morgan, MD, and colleagues. The research team reports its findings in the November issue of the American Journal of Respiratory and Critical Care Medicine.

"Patterns of wheezing prevalence and levels of lung function are established by age 6 years and do not appear to change significantly by age 16 years in children who start having asthma-like symptoms during the early preschool years," Morgan and colleagues write.

4 Wheezing Patterns

In their first report on these randomly selected children in Tucson, Ariz., Morgan and colleagues found four wheezing patterns:

• Never wheezers
• Transient early wheezers, who had a wheezing lower respiratory infection before age 3
• Persistent wheezers, who were wheezing by age 3 and still wheezing when they were 6
• Late-onset wheezers, who did not wheeze by age 3 but began wheezing by age 6

The news is good for late-onset wheezers. At age 16, their lung function was similar to that of kids who never wheezed.

The news is worse for transient early wheezers. Fewer than one in four were still wheezing at age 16 -- and those who did had only infrequent wheezing episodes. Nevertheless, they had worse lung function at ages 11 and 16 than kids who never wheezed.

Like the transient early wheezers, the persistent wheezers also had poorer lung function than never wheezers.

"Individuals who enter adult life with lung-function deficits are more likely to develop chronic obstructive pulmonary disease during the late adult years, especially if they had lower respiratory illnesses in early life," Morgan and colleagues write. "Whether transient early wheezers are also predisposed to chronic obstructive pulmonary disease is, at present, unknown."

The researches speculate that allergic asthma during early childhood -- when the lungs and airways undergo rapid growth -- may lead to changes in lung structure.

SOURCES: Morgan, W.J. American Journal of Respiratory and Critical Care Medicine, November 2005; vol 172: pp .1253-1258. News release, American Thoracic Society.