People who have eczema as a child are nine times more likely to develop allergic asthma as an adult. That is the result of a new study out of the University of Melbourne, the Murdoch Children’s Research Institute, and Monash University. The research is a follow-up to a study that began in 1968. The Tasmanian Longitudinal Health Study (TAHS) recruited all school children in Tasmania who were born in 1961 to participate in an asthma research study. Over 8,500 students participated in the study which included questionnaires about respiratory health and lung function testing.
In 2004, researchers followed up with the test subjects who were 44 years old at that time. The participants completed another survey about their respiratory health and had a skin prick test to check for allergies. Pamela Martin, a University of Melbourne PhD student who analyzed the results said, "In this study we see that childhood eczema, particularly when hay fever also occurs, is a very strong predictor of who will suffer from allergic asthma in adult life."
This trend from eczema to asthma is one example of a sequence doctors sometimes call the "atopic march" or "allergic march". When a patient develops an allergy, the body’s immune system is triggered to fight off the allergen that the body believes is attacking. This results in the creation of antibodies known as immunoglobulin E (IgE). Researchers believe that children who develop IgE early in life as a result of eczema and hay fever have a greater tendency to develop allergic asthma later in life.
Asthma is a chronic or long-term lung condition that makes it hard to breathe. During an asthma attack, muscles around the airways constrict and make the airways smaller which makes it harder for air to move in and out of the lungs. At the same time, the airways produce excess mucus which limits air movement. The result is wheezing and difficulty breathing.
Eczema or atopic eczema is a skin reaction that is similar to an allergy. It causes skin inflammation including blisters, itchy skin that may be scratched raw, redness, oozing, and bleeding. Eczema is most common in infants and may be outgrown later in life. Symptoms can become worse due to other factors including allergies to pollen, dust mites, or other allergens, colds or the flu, dry skin, and stress.
Researchers in the Australian study said theirs is the first study to distinguish between allergic and non-allergic asthma as it relates to early eczema and hay fever. They estimate that up to 30 percent of people who have allergic asthma as adults may have developed the condition due to eczema and hay fever when they were children. They hope to develop ways to prevent early eczema from turning into allergic asthma with the dual goal of improving patient health and reducing health care costs for asthma diagnosis and treatment.