Pollen Can Trigger Childhood Asthma

Asthma symptoms increased by weed and grass pollen

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Do you know how much pollen it takes to trigger asthma symptoms? Turns out the answer is not that much at all.

Researchers have discovered that even low levels of pollen can trigger asthma symptoms in children. While parents and children may understand the increased risk of asthma symptoms with high pollen counts, this new study could mean parents need to be careful even during days with low pollen counts.

"Monitor daily pollen counts to help manage asthma."

Led by Dr. Curt T. Dellavalle, School of Forestry and Environmental Studies at Yale University, the study observed 430 children aged between four and 12 years old who had asthma. The researchers compared environmental pollen exposure and asthma symptoms.

Symptoms included shortness of breath, night symptoms, wheeze, chest tightness, persistent cough and rescue medicine use. Symptoms and usage of medication were recorded daily. Tree, grass, weed or total pollen exposure was also measured.

Researchers discovered that children sensitive to either weed or grass pollen had increased symptoms despite a low daily pollen count.

For children sensitive to weed pollen but used maintenance medication, even low levels of weed pollen led to an increase in reports of chest tightness, wheeze, persistent cough, shortness of breath and emergency medication use. The level of pollen was six to nine grains per cubic meter.

That level was lower for children who did not use maintenance medication.

For children sensitive to grass pollen who used maintenance medicine, exposure to two grains per cubic meter led to worsening symptoms. That number was, again, even less for children who did not use maintenance medication.

Parents need to be aware of their child's asthma year-round and not just during peak pollen periods. Parents should take the necessary precautions and limit exposure during high-risk periods. 

This study was published in the November edition of Epidemology.

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Review Date: 
December 6, 2011
Last Updated:
December 6, 2011