Asthma in children has been on the increase since the 80s and the current estimated number of American children with asthma is between 6 and 9 million. It is the leading cause of chronic illness in kids under 18 years old. If your child is sensitive to pollen, a new study suggests that even low levels can increase the chances of an asthma attack. .
Yale and Brown University researchers tracked more than 400 children with asthma, as well as the daily pollen levels near each child's home, over the course of five years. Researchers found that there was a 37% increase in respiratory symptoms in children who were sensitive to pollen- even though pollen levels were very low- and they were taking daily medications to control their asthma.
“In some respects, it's common sense that if a child is asthmatic and allergic to pollen, when they're exposed to pollen, they would bear some risk of asthmatic symptoms," said lead author Curt DellaValle, of the Yale School of Forestry and Environmental Studies.
"The biggest thing, though, is seeing these effects even with the lowest levels of pollen," he told Reuters Health. "It leads us to believe that parents of these asthmatic children should be aware that even when pollen levels are low, their children will experience asthmatic symptoms."
The study also revealed data that surprised researchers. Pollen-sensitive kids that were part of the study had fewer symptoms when ragweed – a major irritant- was at high levels. DellaValle said it may mean that the children's parents reacted to high pollen reports and took extra precautions.
"It suggested that they modified their children's behavior by keeping them inside, in air conditioning or by using air filters," DellaValle said.
Here’s how the study worked:
DellaValle's team recruited 430 children with asthma between the ages of four and 12 in New York, Connecticut and Massachusetts between 2000 and 2003. Each kid's mother kept a calendar tracking her child's asthma symptoms and use of asthma medications. The researchers also tested the children's blood for sensitivity to pollens from trees, grass and weeds.
To get a better picture of realistic pollen exposures, every year during the Northeast's pollen season -- generally from late March to early October -- the researchers used a model to analyze the amount of pollen within 1.2 miles of each child's home. They also tracked daily and seasonal weather, foliage, when pollen seasons began and ended and peak pollen periods.
Among kids with sensitivities to particular types of pollen, even small amounts in the air could trigger asthma symptoms.
Children not on maintenance medication who were sensitive to grass pollen, for example, wheezed, coughed and had trouble breathing and other nighttime symptoms when they were exposed to more than two grains per cubic meter of grass pollen.
Kids on daily maintenance therapy and sensitive to weed pollen could have similar symptoms and a need for rescue medication at pollen levels above six to nine grains per cubic meter.
Among the kids sensitive to weed pollen, low-level exposures raised their risk of symptoms by 37 percent. That compared to a 23 percent rise in risk during the highest weed-pollen periods -- hinting that kids may have stayed indoors when pollen levels were known to be high, the researchers note.
Pollen levels were not tied to an increase in asthma symptoms in kids without allergies to specific pollens.
Parents with asthmatic children often follow pollen reports and adjust their children’s outdoor activity accordingly. This study shows that even low levels of pollen can affect a sensitive child’s breathing and general health.
Although there is no cure for asthma, it can be managed with proper prevention and treatment. There is often a genetic compound.
Asthma symptoms can be mild or severe, and many children’s symptoms become worse at night.
Symptoms may include:
- Frequent, intermittent coughing.
- A whistling or wheezing sound when exhaling.
- Shortness of breath.
- Chest congestion or tightness.
- Chest pain, particularly in younger children.
- Trouble sleeping caused by shortness of breath, coughing or wheezing.
- Bouts of coughing or wheezing that get worse with a respiratory infection, such as a cold or the flu.
- Delayed recovery or bronchitis after a respiratory infection.
- Trouble breathing that may limit play or exercise.
- Fatigue, which can be caused by poor sleep.
If your child experiences any of the above symptoms, make sure he or she is seen by a pediatrician or family doctor.