People with asthma traveling to pet friendly homes for the holidays may want to pack allergy medication along with their inhaler. A study being presented this week at the American College of Allergy, Asthma and Immunology's (ACAAI) Annual Scientific Meeting reveals the number of people with asthma that are also allergic to cats has more than doubled over an 18 year period.
"From 1976 to 1994, positive allergy skin tests in people with asthma have increased significantly," said Leonard Bielory, MD, ACAAI fellow and study author. "Not only have we found the number of asthma sufferers allergic to cats has more than doubled, but those with asthma are also 32 percent more likely to be allergic to cats than those without asthma."
The study also found those with asthma are more likely to be allergic to several environmental triggers common in the fall, including ragweed, ryegrass and alternaria fungus.
An estimated 60 to 85 percent of people with asthma have at least one allergy, according to ACAAI. However, the allergens in which most are allergic to has not been well researched.
"This study helps us better understand common trends in allergy and asthma, which can lead to improved diagnosis and treatment," said allergist James Sublett, M.D., chair of the ACAAI Indoor Environment Committee. "While it is unknown exactly why there has been an increase in asthma and allergy sufferers, it is thought a number of environmental factors can be responsible."
The holidays can suddenly spur allergy symptoms in people with asthma and those that have never before had allergies. For example, while visiting a relative with cats, a runny nose, sneezing and itchy eyes can occur. Then there is the Thanksgiving Effect, where college students return home to a pet they didn't have symptoms to before and are now allergic.
"Allergies can strike at any age in life, with symptoms disappearing and resurfacing years later" said Dr. Bielory. "Allergies and asthma are serious diseases. Misdiagnoses and inappropriate treatment can be dangerous."
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