Asthma Healing

Severe Asthma Begins Early, Lasts Into Adult Years

Kids tend to outgrow mild asthma. But more serious asthma usually continues into adulthood, a 15-year study shows.

It's the kind of asthma study you can't do in a laboratory or hospital. Malcolm Sears, MD, research director of the Firestone Institute at Canada's McMaster University, and colleagues started with a thousand 9-year-old kids born in 1972-1973 in Dunedin, New Zealand. They checked on them at regular intervals. More than 600 were still in the study at age 26.

More than half the kids reported wheezing at one time or another. About one in four of these kids continued wheezing as adults, Sears and colleagues report in the Oct. 9 issue of The New England Journal of Medicine. About half of them had stopped wheezing for a while, but by age 26 their asthma had returned.

Which kids outgrew their asthma and which didn't?

"Mild asthma goes away and serious asthma doesn't," Sears tells WebMD. "The earlier the onset of asthma, the more likely it is there will be a relapse after a period of remission."

Who's At Highest Risk of Lifelong Asthma?

Some kids are at particularly high risk of asthma continuing into adulthood (persistent asthma). They're also at high risk of seeing their asthma come back after going away for a while (recurrent asthma):

• Kids with severe asthma -- technically measured as airway hyperresponsiveness -- were three times more likely to have persistent asthma and three times more likely to have recurrent asthma.
• Allergy to dust mites more than doubled the odds of persistent and recurrent asthma.
• Girls were 1.7 times more likely than boys to have persistent asthma.
• Smoking by age 21 nearly doubled the odds of persistent asthma.
• The earlier children begin wheezing, the more likely they are to have recurrent asthma.

Gerald Teague, MD, director of pediatric pulmonology at the Emory Children's Center in Atlanta, says these findings help doctors tell kids -- and parents -- what to expect.

"The study finds that one in four kids with wheezing have persistent asthma," Teague tells WebMD. "This means I can take a school-age child, call her 6-year-old Brittany, who asks me, 'Am I going to wheeze all my life?' I can say, 'Well, there's a one-in-four chance you will. And Brittany, because you are a girl, and because your asthma started at age 2, you're a little more likely to wheeze -- but you can cut your risk if you don't smoke and if you stay away from things you are allergic to."

Teague stresses the importance of allergy -- particularly allergy to dust mites.

"In asthma, this is the most important allergy of all, and the Sears study says that this one is particularly associated with lifelong asthma," he says.

Asthma Pattern Set at Young Age

Sears' team tried to find out when asthma damaged the lungs. They found that most of the damage already had been done by the time they first saw the kids at age 9.

"This suggests that the damage to the lungs is done early in life," Sears says.

Fernando D. Martinez, MD, director of the Arizona Respiratory Center at the University of Arizona, led an earlier study of asthma in children up to the age of 6 years. His commentary on the Sears study appears in the same issue of NEJM.

"Patterns of asthma seem to be established in early life," Martinez tells WebMD. "The Sears study completes our data -- it starts almost when we stopped. What is most interesting is that these adults continue to have disease similar to the patterns we saw at age 6. Once you have severe asthma at age 6, 7, or 8, it will be severe for the rest of your life. And if it's mild, it's much more likely your symptoms will go away."

What to Do

"The challenge is not just to wait until you have persistent asthma as an adult, but to identify those most likely to have persistent asthma and treat them early," Sears says.

There's no proof -- yet -- that early treatment works. But doctors think this may be the case.

"We are studying that now," Martinez says. "We give our patients the choice of very aggressive therapy. By quelling and controlling the symptoms, we control lung inflammation. Maybe that can change the course of the disease."

Even if treatment doesn't cure asthma, it makes it much, much better. Just because asthma persists doesn't mean a person is doomed to suffer.

"Parents need to know that although we cannot change the natural history of asthma, this disease is perfectly treatable," Sears says. "Nine out of 10 of kids with asthma can have a normal life."

Not all wheezing is asthma, Teague notes. Lots of things can cause wheezing. But it's a sign to take your kid to the doctor. If it's asthma, it's never too soon to know.

"Only 40% of children with periodic wheezing get treated right despite excellent new drugs," Teague says. "Treat it! The best chance for your child to preserve lung function is aggressive treatment early in childhood."

Teague also recommends aggressive steps to reduce dust mites.

"Keep your house dry -- dust mites love humidity," he advises. "Get a hydrometer, a wall-mounted humidity meter, if your house is more than 0.5 humidity, run a dehumidifier. The other thing is to cover the mattress and pillow with a special allergen-proof casing. That is cheap; you can get them in most stores. I'm don't think you have to take the rugs and stuffed toys away. Just wash bedding in super hot water every 10-14 days to kill the mites. And if you really want to get away from them, move to Denver -- dust mites don't like altitude."