Asthma Healing

Many children with asthma appear to outgrow the disease by their mid- to late teens. While they may seem to be cured, a new study suggests one out of three will have a recurrence of asthma symptoms by their mid 20s.

"It is likely that during adolescence, asthma subsides to the point where airway inflammation is minimal and does not cause symptoms," lead researcher Robin Taylor, MD, of the University of Otago School of Medicine says in a news release. "Patients who have a relapse likely have had a change in environment that provokes airway inflammation to the point where asthma symptoms recur."

Some 17 million Americans have asthma -- caused by narrowing airways and airway blockage from inflammation. Allergy triggers and other environmental influences often trigger asthma attacks.

Taylor and colleagues followed more than 1,000 New Zealand children from birth to age 26. More than 170 of them had asthma during childhood -- but 40% of these were free of asthma symptoms by age 18. The findings were reported at this week's American Thoracic Society International Conference in Seattle.

However, by age 21, one in four of the symptom-free young adults reported a recurrence of their asthma, and roughly 35% had relapsed by age 26.

The young adults who had a history of allergies seemed to be the ones most likely to relapse, says Taylor. This tendency towards allergic reactions appears to make the airways in the lungs sensitive to allergy triggers in the environment.

"What we are learning is that asthma is a chronic disease, and even if a person is symptom free it does not mean that the ongoing inflammation that causes the disease isn't still happening," American Thoracic Society president Homer A. Boushey, MD, tells WebMD. "People with a history of asthma need to be aware that they are at risk for recurrence, even if they think they are cured."

Because asthma is much more common in New Zealand than the U.S., Boushey says it is possible that their rate of asthma recurrence is higher as well. But he says the relapse rate in the U.S. is probably close to that seen in the study.

The New Zealand researchers say that healthy teens with a history of asthma may need to consider their increased risk for the disease when they are choosing a career. "The risk of asthma relapse in adulthood may be of concern with regard to occupations where asthma would pose a risk, such as aviation or fire fighting," they noted.

But Boushey, who directs the Asthma Clinical Research Center at the University of California, San Francisco, says this message ignores the fact that asthma is a disease that can be well treated.

"Unless you have unusually severe asthma, it should not interfere with your life to the extent that you can't chose a particular career," he tells WebMD. "People with asthma can do just about anything. There are a disproportionate number of Olympic athletes with asthma."