Allergies and Asthma on the Rise

Plants are most often mankind's good friend — but sometimes, it's the pollen and ragweed that affects us more than the appeal of flowers in bloom.

Nearly 1 in 5 people are affected by allergies and 1 in 12 adults by asthma. New studies and local figures show that number is likely to rise.

There is a clear relationship between asthma and allergies as well. According to a recent survey by Quest Diagnostics — the largest national allergy study to date, called Allergies Across America — patients with asthma were 20 percent more likely to have an allergy, particularly to indoor allergens like mold and house dust mites.

Allergies like these are abnormal reactions of the immune system that occur in response to otherwise harmless substances. 

The symptoms can manifest themselves by sneezing, eye-watering, itchy throat, skin irritations, or rarely, anaphylaxis leading to death.

The Quest study found that over a four year period in certain big cities, including the Riverside-San Bernardino area locally, sensitivity to ragweed has increased 15 percent and to mold by 12 percent. In addition, pollens have been present in record amounts in certain parts of the country because of the unusually heavy winter and spring rainfall.

"Winter and spring precipitation have created a 'perfect storm' for heavy pollen levels and molds," said Dr. Clifford Bassett, medical director of Allergy and Asthma Care of New York. "Higher pollen levels [have] in part [been] from increased carbon dioxide (greenhouse gases) that supercharge plants, trees, etc. to produce and release more pollen."

Experts also say ragweed seasons are getting longer, especially in the Southwest, where it can plague allergy sufferers well into the fall.

Check out pollen.com for a four-day allergy forecast.

Allergies and asthma are related in another way — in the case that allergies can cause or initiate asthma in some. As the prevalence of asthma is increasing, it is estimated that nearly $30 billion is spent annually in the United States to treat the condition. In California, the prevalence rate of asthma was 8.4 percent in 2008, according to a statewide adult, self-reported survey.

According to a new study from the U.S. Centers for Disease Control and Prevention (CDC), allergies affect one in five Americans and asthma affects one in 12 adults and nearly one in ten children in the United States.

More on the Allergies Across America Study:

The most commonly used allergy testing method to test allergies is the skin-prick test, which tests for more allergens than the blood test.

The Immunoglobulin E (IgE) allergy blood test checks for the IgE antibody in blood produced by the body's immune system when an allergen is present. The test result identifies sensitization to one or more of 11 common allergens: five foods (egg white, milk, peanut, soybean, and wheat), common ragweed, mold, two types of house dust mites, and cats and dogs.  The food challenge method of elimination is the third type of test, specifically used for food allergies.

Children exhibiting allergies up to the age of eight that were tested were most likely to experience high rates of food allergies.  Of those children tested, thirty-seven percent of infants and toddlers were sensitive to egg white and 36 percent of three year olds were sensitive to milk.  A total 26 percent of children six to 18 years of age and nearly 30 percent of children under five years old tested positive to peanuts, and almost 25 percent of children under age 10 were allergic to wheat with that rate declining after the age of ten.

Treatments for allergies include allergen avoidance, use of anti-histamines, steroids or other oral medications, immunotherapy to desensitize the response to allergen, and targeted therapy.

Look for a future “Going Green” column about indoor pollutants.