Study points to increasing food allergies among children

Almost 4% of American children have food allergies, according to a sweeping analysis of the problem published today in the journal Pediatrics.

The study is the first to make a broad estimate of the prevalence of food allergies among U.S. children and supports previous, smaller studies suggesting that food allergy rates are rising rapidly for reasons that are unclear.

Researchers from the Centers for Disease Control and Prevention found that self-reported food allergies increased 18% from 1997 to 2007.

The estimates were drawn from surveys of the children's parents and from medical records. Using data from medical records taken in 2005-06, researchers found 9% of all children tested positive for immunoglobulin E antibodies to peanuts. IgE tests are not considered reliable indicators of an allergy, but they do suggest an increased risk or past history of an allergy. The antibody tests were positive for egg allergies in 7% of children, for milk allergies in 12% and for shrimp allergies in 5%.

Finally, the analysis showed that healthcare visits for food allergies in children nearly tripled between the two time periods studied: 1992 through 1997 and 2003 through 2006. In the later period, U.S. children had an average of 317,000 visits to healthcare settings per year for food allergies.

The study also suggests potential racial differences among children with food allergies. While Latino children had the lowest prevalence of food allergies in 2007 compared with other racial groups, they had the greatest increase in reported food allergies over the time period studied.

"We used four different surveys, and to see an increase in food allergies in all of those surveys is very telling," said the lead author of the study, Amy M. Branum of the National Center for Health Statistics. "This is not just limited to one demographic or age group."

-- Shari Roan

Photo credit: Al Schaben / Los Angeles Times

Allergic reaction to vaccines should be investigated

Some people have an allergic reaction after having an immunization, an experience that often -- and quite naturally -- leads to an avoidance of any future immunizations. But new guidelines published this week state that any allergic reaction to a shot should be investigated to understand the cause, rather than just giving up on vaccinations.

About 235 million doses of vaccines are given each year in the United States, and about 235 cases of anaphylaxis, a serious medical reaction, occur. Milder reactions to vaccines, such as redness and soreness at the injection site and fever are common and should not deter people from getting future immunizations, said Dr. John M. Kelso, the chief author of the report.

However, when a serious reaction occurs, the patient should be evaluated by an allergist to determine the culprit allergen. This can be done through allergy testing. Vaccine components that could cause reactions include gelatin or egg protein, yeast, latex from the syringe plungers, neomycin and thimerosal.

Once the problem allergen is identified, individuals and their doctors can make decisions about receiving future vaccines in order to ensure safety.

"Persons with a history of allergy to egg or a past reaction to an influenza vaccine may still be able to receive the H1N1 vaccine or the seasonal flu vaccine safely," Dr. James T. Li, an author of the report, said in a news release. "I believe that anyone with this concern should check with their doctor and consult with an allergist."

The guidelines are online at www.allergyparameters.org.

-- Shari Roan

Mel Melcon  /  Los Angeles Times

Learning to tolerate a peanut allergy

Peanut allergies affect thousands of people and can even produce life-threatening anaphylactic shock in severe cases. With few ways to protect people with a peanut allergy -- other than avoidance -- British researchers have tested a daring new approach to the allergy. They exposed people to peanuts.

The study, published this week in the journal Allergy, was conducted in only four children with peanut allergies. The researchers slowly exposed the children to peanuts over a six-month period, starting with as little as 5 milligrams of peanut protein, which is about one-fortieth of a peanut. Eventually, the children were all able to tolerate up to 10 peanuts (although one child had anaphylaxis during the study and required an adrenaline injection). Though the amount of peanuts tolerated was small, the authors noted, it might protect children who accidentally ingest peanuts hidden in food.

Previous allergy studies have shown people can be desensitized to allergens like pollen and bee stings. But desensitization has never been shown to work with a food-related allergy. The researchers, from Addenbrooke Hospital in Cambridge, told the BBC that the patients should be able to retain their tolerance by eating a small daily dose of peanut protein. The study is continuing in a larger number of people.

-- Shari Roan

Photo credit: Ken Hammond / Associated Press

Those drug-interaction warnings sure are irritating

One can imagine how electronic drug-prescribing systems could be annoying to doctors -- all those warnings about potential interactions and allergies and whatnot when all you really want to do is give a patient a drug he or she needs and be done with it. It's probably easier to just ignore the blasted alerts and keep going.

That seems to be what's happening. In a study published in the Feb. 9 issue of the Archives of Internal Medicine, most doctors simply shrugged off the warnings issued by their helpful electronic systems.

Out of almost a quarter-million medication safety alerts produced during the study period, the doctors involved accepted only 9.2% of the interaction warnings and 23% of the allergy warnings. In other words, they ignored more than 90% of the drug interaction alerts and more than 75% of the allergy alerts.

The researchers at Dana-Farber Cancer Institute and Beth Israel Deaconess Medical Center who conducted the study have posted a list of potentially severe medication interactions -- and the acceptance rates of those alerts.

Obviously, if patients are counting on electronic prescribing systems to completely protect them from dangerous drug interactions and allergies in this bold new world of sophisticated record-keeping and safeguards, they may want to reconsider.

As the study's conclusion dryly notes: "Clinicians override most medication alerts, suggesting that current medication safety alerts may be inadequate to protect patient safety."

-- Tami Dennis

Photo credit: Associated Press

Poor air quality causes big increase in illness

Hospitals may be especially busy this week dealing with illness created by this weekend's wildfires. A study published online this week from UC Irvine that tracked hospital admissions immediately before, during and after the 2003 Southern California wildfires found a significant spike in illnesses.

Dr. Ralph Delfino, an environmental epidemiologist, analyzed more than 40,000 hospital admissions in the weeks surrounding the October 2003 fires that burned nearly three-quarters of a million acres. He found heavy smoke conditions associated with a:

• 34% increase in asthma admissions
• 67% increase in acute bronchitis admissions
• 48% increase in chronic obstructive pulmonary disease admissions
• 45% increase in pneumonia admissions.

The study found that young children, elderly people and teens with asthma were the most effected.

As Booster Shots noted in yesterday's story on the fires and air quality, it is vital for people who are prone to respiratory illnesses to take precautions when wildfires flare. Says Delfino:

It's important to learn from this study that large-scale wildfires can have wide-ranging effects on human health. It will be vital to educate those at risk with existing respiratory conditions to react quickly at the earliest signs of symptoms with preventive interventions.

Delfino's study will be published online this week in the journal Occupational and Environmental Medicine.

— Shari Roan

Photo credit: Allen J. Schaben /Los Angeles Times

Obamas won't find a 'hypoallergenic' dog

Forget the Obama administration cabinet. One of the most pressing issues facing the nation is the selection of First Dog.

President-elect Barack Obama and his wife have promised their daughters that a furry friend will accompany them to the White House. But 10-year-old Malia Obama is allergic to dogs, and the Obamas have expressed a desire to find a "hypoallergenic" dog -- preferably one from a shelter.

However, according to advice released today from the American Academy of Allergy, Asthma and Immunology, the first family needs to temper its hopes. "There is no truly hypoallergenic dog," says the AAAAI in a statement. It's a misconception that dog allergies are caused by the dog's hair. Allergies are caused by protein from the animal's dander, which can be found in dead skin cells, saliva and urine. These microscopic proteins travel through the air and are inhaled, triggering an allergic reaction in, well, quite a few people. A 1994 study in the Journal of Allergy and Clinical Immunology estimated that 2.3% of people have a reaction to dog allergens. That's about 10 million Americans.

Malia and her sister, Sasha, will get their puppy, though. Some dog breeds are considered allergy friendly, says the AAAAI. But that's because they're groomed more frequently. If the White House doesn't have a pet groomer on staff, it will soon.

For tips on avoiding animal allergies, see the AAAAI website.

-- Shari Roan

Photo: A candidate for the Obama White House: Peruvian hairless dog. Credit: Ernesto Benavides/AFP/Getty Images

   

Don't forget to worry about sesame

Preventing peanut allergies, overcoming milk allergies, the rise of food allergies in general ... The reports about reactions to food have been relatively heavy of late:

Study shows avoiding peanuts may increase allergy risk

Kids may be able to overcome milk allergies

Eating shouldn't be dangerous; for many kids, it is

Now the blog Food Allergy Buzz reminds us about sesame. Is FDA's list of top food allergens complete?

Other countries include sesame on their lists of common allergies, says the author, but not the U.S. She urges folks concerned about sesame to push the FDA for advisory labeling.

Reactions do seem to be on the upswing.

-- Tami Dennis

Photo: Tahini cookies, made with crushed sesame seeds.

Credit: Irfan Khan / Los Angeles Times

Study shows avoiding peanuts may increase allergy risk

It's getting harder to know what to do about peanut allergies. In the past, health experts generally recommended avoidance of peanuts during pregnancy, breast-feeding and infancy. But a study published today in the November issue of the Journal of Allergy and Clinical Immunology suggests that it may be better to be exposed to peanuts early in life.

Researchers in the United Kingdom and Israel studied 8,600 Jewish school-age children in the U.K. and Israel to assess the prevalence of peanut allergy. They also asked mothers about the children's peanut consumption at ages 4 months through 24 months. The groups in the U.K. and Israel were similar in genetic, environmental and socioeconomic characteristics. They found that children who avoided peanuts in infancy were 10 times as likely to develop peanut allergy as those who were exposed to peanuts. Overall, children in the United Kingdom had a much higher prevalence of peanut allergy compared to those in Israel. However, by 9 months of age, 69% of the children in Israel had been exposed to peanuts compared to only 10% in the United Kingdom.

American health officials caution that there isn't enough evidence to recommend early exposure to peanuts. Peanut allergies in the United States have increased dramatically, doubling between 1997 and 2002. Peanut allergies can be life-threatening.

"While this study's findings provide optimism for prevention of peanut allergy in the future, randomized, controlled trials are needed to verify that early induction of peanut is indeed effective," said Dr. Jacqueline A. Pongracic, vice chair of the American Academy of Allergy, Asthma and Immunology's committee on adverse reactions to foods. A large, randomized study is underway in the United Kingdom that tests the effects of early peanut exposure.

In a study published online Tuesday, also by the Journal of Allergy and Clinical Immunology and reported Wednesday in Booster Shots, researchers found they could desensitize children with milk allergies by giving them progressively higher doses of milk protein.

-- Shari Roan

Photo credit: Gary Friedman /Los Angeles Times

Kids may be able to overcome milk allergies

Got a milk allergy? Normally, kids with the condition have to avoid milk, treat the reactions that do occur -- or wait to outgrow the allergy. A new study offers the possibility of another approach.

On the heels of a CDC report earlier this month establishing that food allergies are on the rise in children -- up 18% from 1997 to 2007 -- comes some good news from Johns Hopkins Children's Center in Baltimore.

Researchers there were able to desensitize children to milk allergens by giving them progressively higher doses of milk protein, an approach more technically called oral immunotherapy.

Over four months, 19 kids who could tolerate an average of only 40 milligrams (a quarter of a teaspoon) of milk were given either progressively higher doses of milk powder or a placebo. By study's end, the 12 kids who had been given the increasing amounts of milk could tolerate 2,540 milligrams to 8,140 milligrams (2.5 ounces to 8 ounces) of milk without any allergic reaction or with only mild symptoms.

The seven who had been given a placebo could still tolerate only 40 milligrams of milk powder.

Said senior investigator Dr. Robert Wood in a news release:

"Our findings suggest that oral immunotherapy gradually retrains the immune system to completely disregard or to better tolerate the allergens in milk that previously caused allergic reactions. ... Albeit preliminary and requiring further study, these results suggest that oral immunotherapy may be the closest thing yet to a 'true' treatment for food allergy."

The researchers are studying the approach in kids with egg allergies as well. And if you're thinking maybe you could try this on your own ... that's probably not a good idea. Doctors seem to agree on that point.

Here's a WebMD report on oral immunotherapy for peanut allergies.

The new study was published online Tuesday in the Journal of Allergy and Clinical Immunology.

-- Tami Dennis

Photo credit: Luis Sinco / Los Angeles Times

Eating shouldn't be dangerous; for many kids, it is

For kids in the United States, eating is an increasingly risky business. Food allergies among children -- defined as people under 18 -- rose 18% from 1997 to 2007, a new federal report shows.

The report, released today by the Centers for Disease Control and Prevention, found that about 3 million children -- approximately four out of every 100 -- suffered from a food or digestive allergy in the previous 12 months.

The findings, culled from the National Health Interview Survey and the National Hospital Discharge Survey, also included these nuggets:

-- Hispanic kids appear less likely to suffer from food allergies. In the last 12 months, 3.9% of the nation's kids overall reported a food allergy, compared with 3.1% of Hispanic kids.

-- Prevalence shifts with age. In the last 12 months, 4.7% of kids younger than 5 reported a food allergy, compared with 3.7% of those 5 to 17.

-- Allergy-related hospitalizations among children are on the rise, from 2,615 for the 1998-2000 reporting period to 9,537 for the 2004-2006 reporting period.

-- The risk of asthma or other allergies increases dramatically for children with food allergies. They're two to four times more likely to suffer from these conditions than are kids without such allergies. For example, 8% of children without a food allergy suffered eczema or skin allergy, compared with 27% of children with a food allergy. Such statistics suggest hypervigilance on the part of kids and their parents is not unwarranted.

The most common food sources of allergic reactions are milk, eggs, peanuts, tree nuts, fish, shellfish, soy and wheat. The Food Allergy and Anaphylaxis Network offers information on hidden sources of these foods and on how to manage food allergies.

Let's be careful out there.

-- Tami Dennis

Photo: Adding whole grain wheat bread to your diet may be a great idea for many people, but not those with wheat allergies. Credit: Stephen Osman / Los Angeles Times