Though many children with asthma eventually grow out of the condition, a severe case in childhood or allergies to furry animals may each signal asthma that will persist into young adulthood, according to a new study.
Swedish researchers followed seven- and eight-year-olds with asthma through their teens and among those with the combination of severe asthma and animal allergies as kids, 82 percent still had asthma at age 19.
"Asthma is a dynamic condition which often remits but also frequently relapses," said lead author Dr. Martin Andersson of The OLIN Studies, Norrbotten County Council in LuleÃ¥, Sweden.
Risk factors for asthma are complex and make it hard to predict which kids with wheezing or shortness of breath will still have those problems years later, Andersson told Reuters Health. As with previous research, the new study found that girls were less likely to "grow out of" asthma.
However, the link between childhood allergies to furred animals like cats, dogs and horses and persistent asthma later in life had not been seen in previous studies, Andersson said.
To look for factors that might indicate whether a child's asthma is likely to linger, the researchers gave questionnaires to the parents of 248 Swedish children ages seven and eight with asthma in 1996, and checked back in with the parents every year until the kids turned 19.
By the time they were teens, 205 kids remained in the study and 43 of them, one in five, were in remission - defined as three or more years without wheezing or use of medication.
At age 19, according to the report in the journal Pediatrics, 84 kids had persistent asthma and 78 had periodic asthma, a category somewhere in between a persistent case and complete remission.
Kids with persistent asthma took medication or wheezed at age 19 and in at least eight of the nine previous yearly surveys.
Overall, being male and not having animal allergies or severe asthma as a child were linked with more than doubled chances that the condition would go into remission.
Other factors, such as having parents with asthma, living in damp or rural homes and parental smoking did not appear to affect the likelihood that childhood asthma would go away.
But other researchers have found a link between parents with asthma and their kids' risk for the condition, said John Burgess, the author of one of those studies.
"The jury is still out on that one," Burgess, who studies childhood allergies and asthma at the University of Melbourne in Australia, told Reuters Health by email.
Still, the new study's other results are interesting and appear to be consistent with most findings in the field, he said.
Parents of kids with asthma need to know that the condition often goes away, but there is no guarantee that it will, Burgess said.
"Asthma accompanied by allergies in childhood is a more difficult problem," he added.
"It seems clear that the mixture of asthma and allergy in childhood is not such a good thing in terms of asthma going away," he said.
Future research may explore the relationship between pet ownership, allergies and asthma, but that's not work being done yet, Andersson said.