The Allergic March – Is It Possible to Prevent Allergies and Asthma?



Allergic_March_Feature2By Liz Potasek 

Katie Kastan was worried. Her infant daughter Lucy was unusually fussy and having trouble falling asleep. One pediatrician wrote off her concerns as typical new mother paranoia.

Allergic_March_Chart2Then Katie, who lives in Lino Lakes, Minnesota, noticed Lucy’s skin was red and itchy – eczema.

Lucy was showing signs that suggest early allergic disease.

In young children, allergies often first express themselves as eczema. The skin condition can also be associated with food allergies, ear infections, allergic rhinitis and asthma – the so-called allergic march.

Katie brought Lucy to an allergist for testing after she later showed signs of food allergies. The allergist found Lucy has peanut and dairy allergies. Soon after Katie was found to be allergic to pollen and dogs. “If she gets licked by a dog, she breaks out in hives,” Katie says.

Now age 4, Lucy is experiencing fewer allergic reactions to dogs – instead of progressing to a more severe response.

Breaking the Link

Is there anything Katie and parents of children with asthma and allergies can do to halt the allergic march? There are no easy answers – the solution likely lies somewhere in a tangle of genetics, environmental factors and diet.

Building a Strong Immune System Has Protective Benefits

  • Eat a variety of healthy foods.
  • Stay active – exercise regularly
  • Spend time outdoors and soak up vitamin D
  • Avoid allergy and asthma triggers: pollen, mold, dust mites, air pollution and tobacco
  • Maintain a healthy weight
  • Get plenty of sleep

That advice has changed dramatically with findings of two recent studies in The New England Journal of Medicine.

But as researchers continue to study what causes asthma and allergies, they have discovered interventions may be possible.

Recent studies in The Journal of Allergy and Clinical Immunology suggest an expectant mother’s diet during pregnancy may influence whether the baby develops food allergies, allergic rhinitis and asthma.

One 2014 study found eating peanuts in the first trimester of pregnancy was associated with a lower risk of the child developing peanut allergy.

Similarly, consuming milk in the first trimester reduced the odds of the child getting allergic rhinitis and asthma. Eating wheat in the second trimester reduced the risk of the child developing atopic dermatitis, a form of eczema.

The take-home message? “Including these foods could be beneficial for allergy and asthma prevention,” says allergist and immunologist Supinda Bunyavanich, MD, lead author of the study and assistant professor of pediatrics at Mount Sinai Hospital in New York. “We don’t recommend avoidance of specific foods during pregnancy.”

A 2016 study by Dr. Bunyavanich found that higher intake of food-based vitamin D by expectant moms – the equivalent of an 8-ounce serving of milk each day – reduced the risk of their children getting allergic rhinitis, or hay fever. The study did not find any link between taking vitamin D supplements and
allergic rhinitis.

“My advice to pregnant moms would be to consider including vitamin D-rich foods in their diet,” Dr. Bunyavanich says. “A lot of vitamin D-rich foods are foods that are healthy for us to eat anyway,” she says. These include dairy products, cereals, fish, eggs and mushrooms.

A LEAP Forward

In recent years there has been renewed focus on when to introduce certain solid foods to babies. Parents were previously told to avoid giving infants common food allergens such as peanut, egg and milk, believing early introduction led to food allergies.

 

Benefits of Breastfeeding

Numerous studies show regular breastfeeding in the first year of life may decrease the likelihood of developing asthma, eczema and cow’s milk allergy. The most recent study, from researchers at the University Children’s Hospital Basel in Switzerland, revealed breastfeeding can even protect children who have a gene associated with asthma risk.

That advice has changed dramatically with findings of two recent studies in The New England Journal of Medicine.

The Learning Early About Peanut (LEAP) study in 2015 found infants at high risk for peanut allergy who regularly ate small amounts of peanut protein were less likely to develop peanut allergy. The Persistence of Oral Tolerance to Peanut (LEAP-On) study in 2016 revealed the same at-risk infants still did not develop a peanut allergy even after they had avoided eating peanuts for one year.

Doctors now advise parents of at-risk children – those who are allergic to egg, have moderate-to-severe eczema, or have a sibling with peanut allergy – to speak with an allergist before introducing peanut into their child’s diet.

“We really try to get them in early, screen them, and introduce the food if we can,” says Bruce J. Lanser, MD, director of the Pediatric Food Allergy Program at National Jewish Health in Colorado.

These studies and others have also changed how doctors advise parents of children at no or low risk of peanut allergy. “We’re telling pediatricians to open babies’ diets, encourage broad food introduction early in the first year of life (between 4 to 6 months), and try foods that are considered highly allergenic,” Dr. Lanser says.

While the study results are promising, more research is forthcoming. It’s unclear whether the study can be expanded to other food allergens and there’s also no definite answer on how often a child should eat peanut – and how much – to build tolerance.

Strict avoidance is still urged for people diagnosed with a food allergy.

From Eczema to Asthma

For many children, the allergic march begins with eczema – it often develops in the first 6 months of life. Eczema is not always an allergic disease, but allergens can often play a role. Food allergens can cause an eczema flare-up, as can common indoor allergens such as dust mites and pet dander.

 

Can Immunotherapy Help?

Allergen immunotherapy – in which patients are given small, increasing doses of an allergen in order to build tolerance and reduce symptoms – may prevent the progression of allergic rhinitis to asthma, as well as stop new allergies from developing, according to an article in Allergy, a medical journal of the European Academy of Allergy and Clinical Immunology. Talk with an allergist to find out if allergy shots or under-the-tongue immunotherapy tablets
are right for you.

That advice has changed dramatically with findings of two recent studies in The New England Journal of Medicine.

Recent research suggests eczema serves as the first site where allergies make an impact – preceding the development of nasal allergies and asthma. Research also indicates there may be a window of time to treat eczema and prevent or delay the development of allergies.

Parents should speak with a pediatrician if eczema emerges in early childhood. One way to prevent skin problems early on is to routinely moisturize the skin.

“We’ve found the best thing to do from the get-go with babies is to use a low-allergenic moisturizing skin cream,” says Nancy Ott-Pinckaers, an allergist with Allergy & Asthma Specialists, P.A., in Minneapolis.

Reducing contact with dust mites early in life may help as well. Research around pet dander is mixed, however – some studies suggest exposure to cat and dog dander can cause allergies, while others say it is preventive.

Ear infections, or otitis media, are common in babies but allergies do not cause them, according to the American Academy of Otolaryngology – Head and Neck Surgery. However, allergies may play a role in causing ear infections in children ages 3-6, particularly those who develop inflammation in nasal sinuses.

Food allergies in childhood are also a risk factor for allergic rhinitis (hay fever) and asthma.

In a recent study of 363,000 children and teens with food allergy, researchers at Children’s Hospital of Philadelphia found 35 percent – particularly those with an allergy to milk, peanut and egg – developed allergic rhinitis while 35 percent developed asthma. Asthma risk was higher for those with multiple food allergies than those with an allergy to a single food.

At Risk For Asthma

• Exposure to tobacco smoke

Numerous studies show the negative impact of secondhand cigarette smoke on unborn babies, infants and children – making them more susceptible to asthma, allergies and other health problems. Smoking during pregnancy can change the baby’s genetic makeup, with changes linked to impaired lung function in early childhood, according to a 2016 study in Molecular Systems Biology.

• Obesity

There is a strong link between obesity and asthma independent of the allergic march. Excessive weight gain during the first two years of life can affect lung function
and increase the risk of developing asthma by age 6, according to a 2014 study in Annals of Allergy, Asthma
and Immunology.

• Living in an urban area with air pollution

A 2013 European study shows exposure to air pollution at a young age – especially from truck and car exhaust – can put children and adolescents at greater risk of developing asthma than those living with less pollution.

Reviewed by Bradley Chipps, MD, Stanley Fineman, MD and Mary Cataletto, MD, AE-C