Latest Study on Allergies and Allergy Testing

by Kelley Lindberg


Last month, a new study on allergy testing from Quest Diagnostics, manufacturer of the ImmunoCAP® IgE blood test for allergy diagnostic testing, was released. Quest Diagnostics used its access to the largest national database of allergy blood test results – with results from two million patient encounters – to analyze the effect of allergies on the health of Americans. The 4-year study didn’t measure the prevalence of allergies in the general population (plenty of other studies have done that). Instead, it looked at people who were already suspected of having allergies (both food and environmental allergies), in an effort to see how allergies are changing or affecting the allergic population.

Some of the study’s key findings include:

• The overall sensitization rate (patients having an allergen-specific IgE) increased by 5.8% over 4 years.
• The number of patients tested for allergies increased over those 4 years by 19%, which Quest says is significantly faster than the growth in general laboratory testing.
• Sensitization to ragweed and mold is increasing rapidly, which is consistent with other studies that show climate change may be linked to an increase in environmental allergies (because of the change in growing habits of plants, for example).
• Men showed higher sensitization rates than women.
• Children showed higher sensitization rates than adults.
• Peanuts were the most common food allergen in kids who were tested for food allergies, with 30% of the kids under 5 years of age and nearly 25% of the kids from 6 to 18 testing positive for peanut.
• Patients with asthma have more allergies (averaging 4.1 allergens per person) than patients without asthma (averaging 3.4 allergens).

Another interesting part of the study is that it confirms the “Allergy March,” which shows a disease progression where children with sensitivities often develop different allergic diseases as they mature, for example: moving from a single food allergy in childhood, to environmental allergies, to asthma.

In most cases, this study seems to be confirming what we already know or at last suspected about allergies and allergy testing from smaller studies. This study is significant, however, because of the sheer size of the patient base, and the fact that it used blood tests rather than patient-response surveys for its data.

To read the complete study and learn more about its findings, click Quest Diagnostics Health Trends Allergy Report 2011, “Allergies Across America.”