Ear Infections Linked to Asthma
Kids in Day Care May Be Especially Vulnerable
May 10, 2004 -- For young children, frequent ear infections may mean an increased risk of developing asthma, a new report shows.
The skyrocketing prevalence of asthma has been attributed to many factors: genetics, childhood infections, home environment, and psychological problems. Several recent studies have pointed more directly to a link with repeated infections in early childhood.
For example, "the incidence and the prevalence rates of ear infections have increased significantly over the years, with a parallel rise in asthma rates, particularly in developed countries," writes lead researcher Kamal Eldeirawai, MS, an epidemiologist with the University of Illinois at Chicago.
The study looking at this pattern appears in the May issue of the journal Chest.
The nationwide study involved 7,538 white, black, and Mexican-American children between 2 and 11 years old. Parents completed surveys that asked about various health issues including asthma, wheezing, and ear infections.
The researchers found:
- The more ear infections a child suffered, the greater the child's likelihood of having asthma and wheezing.
Three or more ear infections meant twice the asthma risk compared with no ear infections.
Children with ear infections also had more wheezing, even if they were not diagnosed with asthma.
Children in day care had more ear infections.
"Our findings indicated a significant association between a history of ear infections and ... wheezing," writes Eldeirawai. However, not all children who wheeze have asthma, he points out.
One possible scenario: The same virus that repeatedly infects the middle ear may play a major role in asthma or wheezing, he says. Or antibiotics that are commonly prescribed to treat ear infections may trigger the risk of asthma -- an angle not addressed in this study. Some studies have also suggested that day care and large families help "immunize" a child against asthma, writes Eldeirawai.
In his study, children of well-educated parents were more likely to be enrolled in day care -- and more likely to have recurrent ear infections, as this study also showed. Possibly, this is because they have better health benefits and more knowledge about ear infections and asthma -- and are thus more likely to report it. He cautions that his study relies on parents' memories, which can be flawed.