Winter Birth Increases Food Allergy Risk in Inner-city Asthmatic Children

Inner-city asthmatic children who were born in the winter (December, January and February) are more likely to be sensitized to egg, peanut or soy allergens than their counterparts who are born in other seasons, according to a recently published study in the Journal of Allergy and Clinical Immunology.

A multi-center research team, led by J. Andrew Bird, MD (University of Texas Southwestern Medical Center, Dallas) analyzed serum and historical information for 427 inner-city children with asthma. Eighty-two percent of the children were African American. Sixty-four percent were males, ranging in age from five to eight, and most lived in the northern U.S. (predominantly in Boston, Chicago or the Bronx). The researchers looked for a relationship between the children’s season of birth and the likelihood that they were sensitized to milk, egg, peanut, tree nuts, soy, codfish, shrimp or various indoor allergens (cockroach, mold, dust mites). They also analyzed the data to see if there was a relationship between allergen sensitization and the children’s vitamin D status, but did not find one. In addition, the study found no relationship between winter birth and sensitization to indoor allergens.

Previous studies have found an association between food allergies and season of birth, but they have focused primarily on Caucasian children. This is the first study to establish a connection between winter birth and sensitization to egg, peanut and soy in a predominantly black, inner-city population. The authors suggest more research be done to determine whether other factors, including winter viruses, geographic location and indoor allergen exposure, may affect food allergen sensitization during the winter.

Researchers Discover Cause of Eosinophilic Esophagitis

Researchers report that they have discovered the cause of eosinophilic eophagitis (EoE), a hard-to-treat food allergy. In EoE, large numbers of white blood cells, known as eosinophils, accumulate in the lining of the esophagus (the tube that connects the mouth to the stomach), causing chronic inflammation. Led by a team at Cincinnati Children’s Hospital, investigators have found a new genetic and molecular pathway in the esophagus. This discovery, reported online today in Nature Genetics, opens the door to new therapies for EoE, which has been diagnosed in a growing number of children and adults over the past decade.

The study found that EoE is triggered by the interplay between epithelial cells, which help form the lining of the esophagus, and a gene called CAPN14. When the epithelial cells are exposed to an immune hormone called interleukin 13 (IL-13), which is known to play a role in EoE, they cause a dramatic increase in CAPN14. CAPN14 encodes an enzyme called calpain14, which is also part of the disease process. Because drugs can target calpain 14 and modify its activity, the study opens up new therapeutic strategies for researchers to explore.

drmarkrothenberg125x156“In a nutshell, we have used cutting-edge genomic analysis of patient DNA, as well as gene and protein analysis, to explain why people develop EoE,” says Marc E. Rothenberg, MD, senior investigator on the study. “This is a major breakthrough for this condition … Our results are immediately applicable to EoE and have broad implications for understanding eosinophilic disorders as well as allergies in general.” The study was funded, in part, by the National Institutes of Health (NIH), with additional support from other organizations, including FARE.

Study: People with Eczema Should Avoid Food-Based Skin Products

If you have a skin inflammation such as eczema, using skin cream that contains food ingredients could lead to an allergic reaction, according to a letter to the editor published in the Journal of Allergy and Clinical Immunology: In Practice.

Australian researchers report on the case of a 55-year-old woman who had a life-threatening reaction after eating two mouthfuls of a salad containing goat cheese. Although the woman suffered from eczema and seasonal asthma throughout her life, she had no history of reactions to food. But after conducting tests to track down the problem ingredient, doctors found that she was allergic to goat’s milk.

Further investigation revealed that the woman frequently used a moisturizer containing goat’s milk to soothe her eczema, although she stopped using it when her condition worsened. Rubbing the cream into inflamed skin, however, presumably sensitized her. When she ingested goat cheese, it triggered a reaction that escalated within minutes, requiring emergency treatment with epinephrine.

The researchers believe that this is the first direct evidence that humans can become sensitized to a food allergen by exposure through the skin. However, previous studies suggest that people with eczema have developed food allergies after using soaps and oils that contain wheat, oat, peanut and goat’s milk. The authors advise eczema patients to avoid skin care products and cosmetics that contain food ingredients.

Food Allergens in Medications

A new clinical review provides useful information about the potential presence of food allergens in prescription medications. Although some medications and vaccines do contain substances derived from foods, researchers found that most medications do not contain enough of a food protein to cause an allergic reaction.

In the article published in the June 2014 issue of the Journal of Allergy and Clinical Immunology, Dr. John M. Kelso (Scripps Clinic, San Diego, CA) explains that all medications contain excipients, substances that are added to the active ingredient of a drug during the manufacturing process. Examples include flavoring agents, preservatives and binding materials. The article offers a thorough review of medications that contain food-derived excipients and discusses whether each is safe for patients with food allergies. For example, the MMR (measles-mumps-rubella) vaccine contains negligible or no egg protein and can be given to anyone with egg allergy. The typically available influenza vaccine contains trace amounts of egg protein, but authoritative professional associations have issued statements recommending vaccination for those with egg allergy and declaring that it may be administered safely with some precautions.  On the other hand, some vaccines, including MMR, may trigger a reaction in people who are allergic to gelatin. Fortunately, this allergy is not common. People with fish allergy may safely consume fish oil, since it does not contain fish protein.

Dr. Kelso further notes that if a person does have a reaction to a medication, the drug may be from a specific lot that was accidentally contaminated with food protein. “In most circumstances these medications should not be routinely withheld from patients who have particular food allergies because most will tolerate the medications uneventfully,” he writes. “However, if a particular patient has had an allergic reaction to the medication… allergy to the food component should be investigated.”

Exploring the Natural History of Egg Allergy

eggEgg allergy is among the most common food allergies in children. One of the most comprehensive examinations of the natural history of egg allergy to date was published in the February 2014 issue of the Journal of Allergy and Clinical Immunology. Researchers from the Consortium of Food Allergy Research (CoFAR) set out to describe the natural course of egg allergy and to identify early predictors of the disease. Over a period of 74 months, they tracked the allergy in 213 children who were between 15 months and 3 years old at the beginning of the study.

By age six, approximately half of these children were able to tolerate egg. Compared to children who were not able to tolerate egg, these children had lower levels of egg-specific IgE, the antibody associated with food allergy. Based on these and other observations, the authors of this study—many of whom serve as advisors to FARE—have developed a calculator that may predict the history of egg allergy in individual patients. Further studies are needed to validate the accuracy of this calculator. The study authors estimate that approximately 50 percent of children with egg allergy will become tolerant to egg by the age of 6. The National Institutes of Health (NIH) was the principal funder of this study.

This article was originally published in the Spring 2014 issue of FARE’s Food Allergy News. Read more of the newsletter here.

Access to Health Care and Food in Children with Food Allergy

Access to health care and food are serious concerns for families managing food allergies. A new study, funded in part by FARE, set out to research whether patients with food allergies experience impaired access to these basic needs—a topic which had not previously been evaluated.

The study, led by Christina B. Johns and Jessica H. Savage and published online by the Journal of Allergy and Clinical Immunology: In Practice in February 2014, found that families managing food allergies are more likely to face food insecurity and reduced access to health care. Based on data reported by more than 26,000 parents, the researchers’ analysis found that among families managing food
allergies:

  • 21 percent of children had low food security
  • 34 percent reported having problems paying medical bills
  • 4 percent reported not being able to afford needed prescriptions
  • 3 percent reported not being able to afford needed follow-up care
  • 2 percent reported having trouble finding a doctor to see the child

These values were all significantly higher for children with food allergies than for those without. Additionally, there were significant disparities associated with race/ethnicity. The researchers concluded that “parents of nonwhite children with food allergy were significantly more likely to report difficulty with access to care and food.” This study is noteworthy in that it demonstrated disparities in access among families managing food allergies and opens the door to further studies that can help determine whether improvements in access can improve disease outcome.

The authors are affiliated with Brigham and Women’s Hospital in Boston. Dr. Savage is the recipient of the 2012 AAAAI/Food Allergy Research & Education Howard Gittis Memorial 3rd/4th Year Fellowship/Junior Faculty Research Award. FARE funds this grant, which is awarded annually to a promising young investigator who is selected by an American Academy of Allergy, Asthma & Immunology
committee. This award was created in 2008 to attract gifted researchers to the field of food allergy.

This article was originally published in the Spring 2014 issue of FARE’s Food Allergy News. Read more of the newsletter here.

FARE Supports Research Community at AAAAI’s 2014 Annual Meeting

For the food allergy research community, the annual meeting of the American Academy of Allergy, Asthma & Immunology (AAAAI) is one of the most important events of the year. FARE maintained a high profile at this year’s meeting, which was held in San Diego from February 27-March 4.  FARE’s Medical and Research Advisory Boards met, and FARE representatives offered information about our programs at our booth in the exhibit hall. Most importantly, FARE-funded researchers, along with our medical advisors, gave presentations and led informative sessions.

Less than 10 years ago, few sessions focused on food allergy. This year’s meeting showed how far the field has come, with a wide range of sessions and presentations devoted to potential new therapies, basic science, managing food allergies in schools and restaurants, and psychosocial issues.

Of particular note, researchers presented data on potential treatments for food allergy, with a strong focus on oral immunotherapy (OIT).  Although OIT is one of the most promising treatments in development, researchers still have many questions, including:  What is the optimal dosage?  How can we prevent patients on OIT from experiencing serious reactions?  Can OIT result in tolerance – long-lasting immunological changes that will protect patients even after they stop the treatment? Several new studies are bringing us closer to finding the answers. (It is important to note that the results discussed here are preliminary, and have not yet been published in peer-reviewed scientific journals.)

  • Researchers at the University of Virginia reported on a clinical trial of patients who had been desensitized to peanut after a course of OIT.  By eating a daily maintenance dose of one or two peanuts, some participants were able to achieve sustained unresponsiveness – meaning that they were able to eat peanut without having an allergic reaction.
  • On the other hand, prolonged avoidance of peanuts after completing OIT may lead to a reversal of the beneficial effects of the treatment, according to a study conducted by investigators at the University of North Carolina at Chapel Hill.
  • In a late-breaking abstract, researchers reported that combining OIT with omalizumab (Xolair®), an asthma medication, significantly reduced dosing-related side effects and the time needed to reach the maintenance dose in patients with milk allergy. FARE and the National Institutes of Health (NIH) are funding this multi-center study – the first randomized, double-blinded, placebo-controlled trial to demonstrate the effects of this combination therapy.
  • For more than a decade, FARE has provided partial funding for the development of a Chinese herbal treatment, Food Allergy Herbal Formula-2 (FAHF-2).  A Phase 2 clinical trial is currently underway to test the effectiveness and safety of FAHF-2 in treating peanut, tree nut, fish, shellfish and sesame allergies. At the AAAAI meeting, Dr. Xiu-Min Li (Icahn School of Medicine at Mount Sinai) presented the results of a pre-clinical study, which showed that combining the Chinese herbal formula with OIT reduced adverse reactions and produced greater post-OIT protection in mice with multiple nut allergies. Further studies are needed to evaluate this combination therapy in humans.

As the world’s largest source of private funding for food allergy research, FARE is committed to partnering with AAAAI to attract the most talented investigators to the field. At a benefit held during the meeting, AAAAI announced that FARE had contributed $50,000 to help establish the Allergy, Asthma & Immunology Education and Research Organization, Inc.’s (ARTrust™) $4 million Donald Leung and JACI Editors Allergy/Immunology Research Fund. Currently, the two leading contributors to the fund are FARE and Steve & Nancy Carell. In addition, since 2008, FARE has funded the AAAAI/Food Allergy Research & Education Howard J. Gittis Memorial Fellowship/Instructor Research Awards, which aim to shape the next generation of food allergy investigators. The recipient of the 2014 Gittis Award, who will be selected by an AAAAI committee, will be announced within the coming weeks. Finally, FARE invited young researchers to a reception, where they learned about our research grant program and strategic plan.

To learn more about current food allergy research, visit www.foodallergy.org/research.

Q&A with Dr. Michael Young: Does Early Exposure to Nuts Lower a Child’s Allergy Risk?

Last month, we received significant feedback from the food allergy community on our blog post about a recently published study, “Prospective study of peripregnancy consumption of peanuts or tree nuts by mothers and the risk of peanut or tree nut allergy in their offspring,” which was published in JAMA Pediatrics. To help clarify some of the key takeaways from the study, we asked Dr. Michael Young, one of the study’s authors, to answer a few questions about the study’s results and what that means for individuals and families managing food allergy.

1. Briefly, can you explain the findings of this study?

The children of women who ate peanut/tree nuts 5 or more times a week while pregnant had a 70% reduced risk of developing peanut/tree nut allergies compared to the children of women who consumed nuts less than once a month while pregnant.

2. In one sentence, what’s the main take away?

If a mother eats peanut/tree nuts while pregnant, it does not cause or increase the risk of peanut/tree nut allergies in her children.

3. How do the findings compare to other studies on this topic? 

There are other studies examining the correlation of eating peanuts during pregnancy and the risk of peanut allergy in the children. Some show increased risk, others show that diet makes no difference. One of the strengths of our study is in the methodology, which minimized recall bias (meaning that the reports that mothers gave on their diets were as accurate as possible). Also, our analysis consisted of cases of clinical peanut allergy (both a positive allergy test and history of reaction to peanuts) rather than cases with only one of those components. Our study is the only study to show that higher levels of maternal nut consumption leads to a reduced risk of children with nut allergies, which is more consistent with current studies on early infant diets showing that earlier exposure to food allergens, such as peanut, milk, egg, and wheat, is associated with reduced risk of allergies to these foods.

4. We’ve heard from many women who ate nuts while pregnant and had children who were born with allergies to peanuts and/or tree nuts. Can you explain why their personal experiences differ from what you found?

While our study shows a reduction in risk of approximately 70% with increased nut consumption, it is not 100% risk reduction; there are undoubtedly other risk factors. The cause of the increased prevalence of peanut allergy is presently unknown, but likely has many factors. Further research may well reveal other risk factors that will help explain why this is happening.

5. Based on the findings of this study, what would your message be to mothers who have children with nut allergies?  

The conclusions from our data should reassure these mothers that eating nuts during their pregnancy did not cause their children to develop peanut and tree nut allergies.

6. What about to women who are wondering if they should or should not eat nuts during their next pregnancy? 

Our study did not specifically examine the diets of mothers of children with known nut allergies during subsequent pregnancies and clinical outcomes. In general, our data would indicate that eating peanuts/tree nuts during pregnancy does not cause nut allergies in children. So, a pregnant woman who wished to include nuts in her diet should feel free to do so.

FARE Researcher Receives NIH Grant

We are pleased to announce that a FARE-funded researcher, Dr. Cathryn Nagler of the University of Chicago, has received a multi-year, $1.4 million grant from the National Institutes of Health (NIH). Over several years, FARE has provided more than $1.5 million to Dr. Nagler and her team.

FARE’s support has enabled Dr. Nagler to identify a new strain of “good” intestinal bacteria that may protect the body against allergic sensitization to food. In September 2013, FARE awarded a bridge grant to Dr. Nagler, which allowed her to pursue her studies while awaiting the NIH’s response to her application for a more extensive grant that continues to explore the therapeutic potential of these bacteria.

Dr. Nagler and other experts believe that genetics alone cannot account for the dramatic increase in food allergies. They are exploring the theory that environmental stimuli interact with the immune system to promote allergic disease. To this end, researchers are studying how the microbiome – the vast collection of microbes, such as bacteria and viruses, that inhabit our bodies – influences our health. While some of these microbes cause disease, others keep us healthy. For example, some probiotics (that is, “good” bacteria) help us digest our food, while others regulate the immune system and protect us against “bad” bacteria.

Dr. Nagler and her team have been studying mice to learn how specific environmental factors – such as diet, antibiotics, intestinal worms, and “bad” bacteria – alter the environment of the gut, making the rodents more susceptible to food allergies. Data from previous studies support their theory. Antibiotic use in infancy, in particular, has been linked to the rising incidence of allergic disease. Dr. Nagler has shown that administering oral antibiotics to mice before they are weaned depletes populations of good bacteria from the intestines. As a result, these mice are predisposed to allergic responses to food.

If successful, this mouse model ultimately may enable scientists to develop and test new probiotic formulations, which would be used to prevent food allergy in infants or to enhance the protection that  existing treatments, such as oral immunotherapy, might provide. It is important to keep in mind that, while promising, this potential therapy has not yet been studied in humans.

This innovative research exemplifies a crucial goal of FARE’s strategic plan for food allergy research: attracting gifted investigators to the field of food allergy by providing long-term support that allows them to advance their work and generate enough data to merit larger grants from the NIH and other federal agencies.

To learn more about current FARE studies and our research vision, please visit www.foodallergy.org/research.

Does Early Exposure to Nuts Lower a Child’s Allergy Risk?

ImageAre children more likely to develop a peanut or tree nut allergy if their mothers eat nuts during pregnancy or while nursing? Over the years, a number of studies have attempted to answer this question, but the results have been inconclusive. According to a new FARE-funded study, eating nuts during pregnancy does not cause food allergies in children. Further, although more studies are needed, it is possible that eating nuts may prevent a child from developing a food allergy.

In an article published online by JAMA Pediatrics on December 23, a research team affiliated with Harvard Medical School reported on their study, which suggests that mothers who do not have allergies and who eat nuts during pregnancy may lower their children’s risk of developing a peanut or tree nut allergy. The study, which was funded by FARE, received considerable media coverage.

The team, led by Dr. A. Lindsay Frazier, looked at the history of 8,205 participants in the Growing Up Today Study 2 (GUTS2) – children who were born between 1990 and 1994. The researchers reviewed records of the mothers’ diet immediately before and during pregnancy, and shortly after the infants’ birth. Of this group, 308 children had a food allergy, including 140 cases of peanut or tree nut allergy.

The incidence of peanut or nut allergies was significantly lower among the children of mothers who did not have food allergies themselves and who ate nuts at least five times per month compared to those who ate these foods less than once per month. “Our study supports the hypothesis that early allergen exposure increases the likelihood of tolerance and thereby lowers the risk of childhood food allergy,” the researchers concluded. They noted, however, that additional studies are needed. “The data are not strong enough to prove a cause-and-effect relationship,” commented one of the authors, Dr. Michael Young. “Therefore, we can’t say with certainty that eating more peanuts during pregnancy will prevent allergy in children. But we can say that peanut consumption during pregnancy doesn’t cause peanut allergy in children.”

A study that should shed more light on this issue is currently underway. The LEAP (for “Learning Early About Peanut Allergy”) Study, conducted by Dr. Gideon Lack and colleagues at King’s College London, has been following 640 children since infancy to determine whether or not exposure to peanuts early in life can prevent the development of peanut allergy. This study, which is co-funded by the National Institutes of Health and FARE, should be completed in 2014.