Kate Johnson

March 02, 2015

HOUSTON — Sensitivity to cats and dust mites, identified on skin-prick testing in children up to 4 years of age, might be an indicator of the risk of developing asthma by age 7, according to results of a new study.

This finding could help guide clinicians on the best way to manage respiratory exacerbations in young children, said session moderator Jeff Stokes, MD, from the Creighton University Medical Center in Omaha, Nebraska.

"We know that over half of all children will wheeze in the first 6 years of life," Dr Stokes told Medscape Medical News. "If we could identify children early who will develop asthma, we can be more aggressive in therapy and possibly alter the disease progression. Any tool we can use to identify those children would be helpful."

The study results were presented by investigator Jessica Tan, MD, from the University of Cincinnati Medical Center, here at the American Academy of Allergy, Asthma & Immunology 2015.

The 492 children enrolled in the Cincinnati Childhood Allergy and Air Pollution Study were considered to be at high risk for asthma because of their parents' history of atopy, positive skin testing, and allergic symptoms.

All children underwent skin-prick testing for indoor aeroallergens — including dog, cat, dust mite, and cockroach — when they were 2, 3, and 4 years of age.

On the basis of the skin-prick tests, 328 children were classified as having low sensitivity to indoor allergens, and 33 were classified as having early sensitivity to house dust mite at age 2 that declined by age 4. In addition, 38 were classified as having increasing sensitivity to cockroach over 4 years, 55 as having increasing sensitivity to cat, and 38 as having increasing sensitivity to house dust mite.

 
If we could identify children early who will develop asthma, we can be more aggressive in therapy and possibly alter the disease progression.
 

At 7 years, the children with asthma-like symptoms were objectively assessed with spirometry or methacholine challenge, and 15.9% tested positive.

"Because of the rigorous requirements for diagnosing asthma, we think that this group is not over-representative or misdiagnosed," Dr Tan explained.

The risk for the development of asthma at 7 years — after known risk factors for asthma, such as sex, race, maternal education, and parental history of asthma were controlled — was highest in children with increasing sensitivity to cat and in children with early sensitivity to house dust mite that declined by age 4, she reported.

This risk persisted even after recurrent wheezing and early food sensitivities were controlled for.

For a sensitivity to cat before 4 years, compared with a low sensitivity to indoor allergens, the odds ratio for asthma was 2.3.

For an early sensitivity to house dust mite that declined by age 4, compared with a low sensitivity to indoor allergens, the odds ratio for asthma was 3.4.

If these findings are replicated by other investigators, they could provide an opportunity to identify and treat patients with very early asthma, said Dr Stokes.

"I would be more inclined to treat them with maintenance medications for the prevention of symptoms under the assumption their airways are abnormal, whereas the other children I would treat at the time of their symptoms," he explained.

Dr Tan and Dr Stokes have disclosed no relevant financial relationships.

American Academy of Allergy, Asthma & Immunology (AAAAI) 2015: Abstract 740. February 23, 2015.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....