Dr. Summit Shah
New research that was just presented at the annual Pediatric Academic Societies Meeting has shown that children aged 4 and younger are at a heightened risk for asthma exacerbations than older children and that the risk is highest during two seasons: spring and fall.
To conduct their analysis on the risk for asthma exacerbations – and who is most prone to them – the researchers used electronic health records from Denver, Colorado between January 1, 2011 and March 30, 2016. They looked specifically at the records for people between the ages of 0 and 20, which amounted to 14, 547 people with an asthma diagnosis.
The study identified 3 risk factors for asthma exacerbations: sex, age, and season. Specifically, males were more likely than females to experience exacerbations, children between the ages of 0 and 4 were more likely to experience exacerbations compared to those aged 5 to11 years and those aged 12 to 21 years, and exacerbations were more likely to occur in spring and fall than summer or winter. Summer was the season for which asthma exacerbations were the least likely to occur.
The majority of the individuals from this sample were from low-income families. There were more males (55%) than females within the sample, and Whites and Hispanics were the most represented races within the same. Whites accounted for 55% of the sample, while Hispanics accounted for 51% of it. Blacks made up 22% of the sample, and 23% identified as other or unknown.
While the results of this study may not be generalizable to the overall population, they provide some insight into the risk of asthma exacerbations and may provide information that can be used to prevent exacerbations, especially in cases where risk for exacerbation is elevated. Given the distress that childhood asthma exacerbations cause to both children and their parents, as well as the health-related financial costs, finding ways to prevent these events is a priority among the allergy and immunology communities.
One major challenge in peanut allergy diagnosis is that the tests commonly used to determine if the allergy exists frequently produce false positives. False positives are preferable to false negatives, which would lead to the incorrect assumption that those with peanut allergies do not have the allergy and thereby increase their likelihood of ingesting peanuts and thus their risk for allergic reactions.
However, the existence of false positives makes it difficult to know for certain if some people who tests positive for food allergies based on a skin test or an antibody test are truly allergic to peanuts. The result is that many of these people are then put through food challenges, where they are given increasingly larger doses of peanut proteins until they either have an allergic reaction or are deemed not to be allergic. Going through a food challenge can be unpleasant, especially for those who are allergic to peanuts and therefore experience an allergic reaction during the process.
A new test, called the mast cell activation test, or MAT, can now diagnose peanut allergies with a much higher degree of specificity than the conventionally used skin tests and antibody tests. A study showing that this degree of specificity is approximately 98% was recently published in the Journal of Allergy and Clinical Immunology.
As part of their investigation into a peanut allergy test with high specificity, the researchers studied 174 children, 73 of whom had peanut allergy, 60 of whom were sensitized to peanuts but not allergic, and 41 of whom were neither sensitized nor allergic. They looked not only at the activation of their mast cells, which is certain cells of the immune system known to be involved in allergic reactions but also at the activation of a similar type of cell, called basophils.
Given that testing mast cell activation provided a higher degree of specificity for diagnosing peanut allergy than did testing basophil activation, the researchers concluded that MATs are the more promising test for helping to diagnose peanut allergies in the context of current methods for diagnosis and their specific limitations. Future work will focus on adapting MAT to other types of food allergies, such as those to milk, eggs, and other seeds and nuts. The hope is that eventually, far fewer patients will have to undergo food challenges to determine whether they have food allergies.
Food Allergy Research and Education, the largest private funding source for food allergy research and the leading organizing that supports people living with food allergies, were involved in a study that was published in April and provides hope that a vaccine against peanut allergies may soon be a reality. Given that the only FDA-approved approaches to food allergies are currently avoidance and inhibiting the food allergy once a reaction has started, the potential for a medical intervention that could prevent an allergic reaction when peanuts are ingested is incredibly exciting for those who deal with peanut allergies. Often one of the worst things about peanut allergies is the anxiety associated with the idea of accidental ingestion of peanuts.
The research, published in the Journal of Allergy and Clinical Immunology, involved an ultrafine nasal spray that was tested in mice. The spray vaccine that was used offers a type of immunotherapy, which is a strategy that has become popular for combatting food allergies. Immunotherapy involves introducing people to small amounts of the substance to which they are allergic so that their immune system learns to recognize that substance as harmless and ceases to react to it. The impact of other immunotherapies on peanut allergies have been tested but have only been shown to help subsets of patients or to help patients only for a certain amount of time.
The vaccine tested in this study was made of peanut protein and a nano-emulsion. The purpose of the peanut protein is to train the immune system to handle peanuts, much like other immunotherapies. The nano-emulsion makes the vaccine different from other immunotherapies, however. Because nano-emulsions have been shown to encourage strong immune responses that seem to fight infections, the researchers reasoned that nano-emulsions could help redirect the immune system when an unnecessary immune reaction may otherwise occur in response to peanuts. In other words, the nano-emulsion may be able to distract the immune system, making it focus on other activities rather than overreact to innocuous peanut proteins.
The researchers gave mice that were induced to have peanut allergies three intranasal doses of the vaccine over a two month period. Two weeks later, these mice did not have the same allergic reaction to peanuts as those that had not undergone the vaccine treatment. The researchers are therefore hopeful that this strategy could also help those with peanut allergies and prevent reactions that could occur if they were exposed to peanuts.
Given that severe allergic reactions have increased dramatically in the past decade, enhancing the emergency care incidents by almost 400%, innovative strategies to overcome peanut allergies are certainly needed. More research will help to determine if a vaccine for peanut allergies will become a reality that can help patients.
The Centers for Disease Control and Prevention (CDC) have put out their National Health Interview Survey, and it has shown a surprising result: healthcare workers are more likely than those in any other industry to suffer from allergies. It is often assumed that exposure to the environmental agents associated with agriculture, manufacturing, and especially mining could sensitize workers and create allergic conditions like asthma in those working in those industries. The CDC found that healthcare workers have asthma more frequently than those in these other industries was, therefore, an unexpected finding for many healthcare stakeholders.
According to the CDC data, healthcare and social assistance workers experienced asthma at a rate of 8.8%, whereas 6.1 % of those working in mining, 5.4% of those working in manufacturing, and 5.2% of those working in agriculture experience asthma. The report highlighted that asthma currently occurs most in workers between the age of 18 and 24, women, non-Hispanic African Americans, those with more than a high school education, and those who live below the poverty line.
The report, published in the Morbidity and Mortality Weekly Report also put forth that healthcare workers were more likely than workers in other industries to not only be diagnosed with asthma but to experience asthma attacks and to end up in the emergency room as a result of their asthma. The reasons for the heightened risk for asthma among healthcare workers may have to do with some of the sterilization procedures with which they are involved and the associated environmental stimuli, including powdered latex gloves and disinfecting products. Aerolized medications may too play a role.
This revelation of the prevalence of asthma among healthcare workers is a first step toward determining how to protect these workers and their health. More research is needed to understand exactly why employees in the healthcare field are more likely to have asthma, and as these reasons are clarified, targeted research strategies should enable us to find ways to intervene such that we can reduce this risk among the large healthcare worker population.
For those who receive or are thinking of receiving allergy shots for allergies such as those related to grass pollen, ragweed, or dust mites, there is an alternative that has been deemed effective by the American College of Asthma, Allergy, and Immunology. Unlike allergy shots, or subcutaneous immunotherapy, which involves injections, the alternative, called sublingual immunotherapy, or SLIT, involves simply placing a tablet under the tongue and letting it dissolve.
Immunotherapy is a strategy that involves exposing an allergy patient to tiny doses of the substance to which the patient is allergic, and increasing the exposure dose over time. This approach works in treating allergies because it trains the patient’s immune system to understand that the allergen is not dangerous. Indeed, allergies represent the immune system’s mistaken interpretation of
Whereas subcutaneous immunotherapy, which means immunotherapy under the skin, can be painful for patients and cause anxiety, sublingual immunotherapy – i.e. immunotherapy under the tongue – is non-invasive and a preferable alternative for many patients, particularly children and those afraid of needles.
In Europe, SLIT has been used for decades for a number of allergens. In the U.S. the Food and Drug Administration (FDA) has approved SLIT for some – but not all – allergens. Currently, patients have been able to get SLIT for some grass pollens and ragweed for years, and more recently, patients have been able to get SLIT for dust mites. Oralair is the SLIT that works against five distinct grass pollens, and Grastek works for certain grass and ragweed allergies. The newest SLIT treatment for dust mites, called Odactra, became available a couple of months ago.
Age is still one limitation with SLIT approaches. For instance, patients must be 5 years old to start Grastek, 10 years old to start Oralair, and 18 to stair Odactra. For patients who are particularly young, sublingual immunotherapy may work better as drops rather than tablets. Cat dander is one allergy for which doctors recommend sublingual drops more than tablets.
Some people should not use sublingual immunotherapy, however. These people include those with uncontrollable asthma, immune disorders, and eosinophilic esophagitis disorder. The risks of serious allergic reactions with SLIT, however, are far lower than those with allergy shots. However, it is generally recommended that those who use SLIT as their form of therapy also carry an EpiPen in case of emergencies.
A new experimental treatment for children with peanut allergies, called AR101, has given way to promising Phase 3 clinical trial results. A biopharmaceutical company from California, called Aimmune Therapeutics, led the study into how safe and effective this new treatment is. They collected data from 554 patients, aged 4 to 17, who suffer from peanut allergies. The study was conducted across 69 sites within the United States.
The researchers split participants into a control group and an experimental group, with the former group receiving a placebo treatment, and the latter grouping receiving AR101 The investigation was performed as a double-blind study, meaning that neither the participants nor their health care providers were aware of whether the participant had received peanut powder or placebo. The logic for using this double-blind approach is to ensure that there is no bias in evaluating peanut tolerance at the end of the trial.
By the end of the yearlong clinical trial, more than two thirds of the group that received AR101 could tolerate the equivalent of about two peanuts, or 600 mg of peanut protein powder, without experiencing an allergic reaction. By comparison, only 4% of those who had received only the placebo intervention could tolerate a 600 mg dose of peanut protein powder a year after the trial began.
The majority of those from the experimental group that could handle a 600 mg dose of peanut protein after a year of treatment could also handle a 1000 mg dose. Whereas only 2.4% of the placebo group could tolerate 1000-mg of peanut protein at the end of the trial, 50.3% of the experimental group could handle this larger dose without incident.
In addition to the promising results of AR101, with respect to the treatment’s ability to protect children against severe allergic reactions to relatively small doses of peanut protein, the study also showed promising results in terms of safety. Only a small proportion of study participants experienced serious adverse side effects.
Some interventions for peanut allergies aim to aggressively reverse allergies or allergic reactions so that patients can safely eat peanuts like those without allergies. The rationale behind AR101, however, was to simply protect children from accidental peanut exposures. Given that 2.5% of children are now allergic to peanuts, up 21% since 2010, treatments like AR101 that may help prevent severe reactions including anaphylaxis in the unfortunate event of peanut exposure are critical for protecting children and for providing peace of mind to those with peanut allergies, as well as their loved ones.
The Centers for Disease Control and Prevention (CDC) has just published results of a study into the prevalence of asthma amongst children in the United States. According to their findings, asthma attack rates have improved a bit in recent years, and fewer children are being admitted to the hospital for asthma attacks. In addition, children have missed fewer days of school in recent years due to asthma attacks.
According to the CDC, that 61.7% of children with asthma experienced attacks in 2001, where only 53.7% of asthmatic children experienced these attacks in 2016. Perhaps more impressive is the drop in hospital admissions. In 2003, 10% of children with asthma were admitted to the hospital, but in 2013, this figure had dropped to only 5%.
The overall rate of asthma amongst children has not gone down in recent years, so there has been some speculation as to the reduction in attacks and hospital admissions. Experts have pointed to the fact that more children now follow an asthma action plan, meaning that more children are now trained to recognize symptoms of asthma and respond to them in a timely way. These action plans can prevent full-blown asthma attacks and the need for hospitalization.
In addition to the improvement in asthma attacks and hospitalization, the CDC report also provided other data on childhood asthma in the United States. For instance, in 2016, asthma attacks were most common among children who were 4 years old or younger. Additionally, asthma among children of Mexican heritage increased from 5.1% in 2001 to 6.5% in 2016.
Based on the results of the study, it is important to ensure that asthmatic children understand asthma and their own triggers and symptoms. Having an action plan in place can be helpful not only in preventing major asthma attacks and visits to the hospital, but it can also reduce anxiety about these types of events. With the flu being particularly severe this year, it is also critical to remember that the flu can exacerbate asthma symptoms. Being prepared to deal with the sudden onset of asthma symptoms can protect children from the physical and emotional stress of an attack.
Researchers at Aarhus University have made a serendipitous discovery that could help an enormous amount of patients who suffer from allergies. Though they were searching for a way to improve existing allergy treatments, their data pointed to a new way to approach allergy treatment. Their results, published in Nature Communications, demonstrate how an antibody can be used to block the immune reaction that leads to allergy symptoms.
Normally, when patients with allergies are exposed to allergens, they produce large amounts of IgE molecules. These molecules travel through the blood and attach to immune system cells called effector cells. When this attachment occurs, histamine production is triggered, which leads to the allergic reaction that the patient experiences.
What scientists have found is that there is an antibody that can interfere with this binding of IgE to two types of effector cells (called CD23 and FceRI). Not only does the antibody block the IgE molecules from attaching to these effector cells, but it can also remove IgE molecules from effectors cells after they have become bound to them.
Certain features of this new antibody make it interesting to researchers and clinicians. For instance, it is much smaller than other antibodies that are currently used in allergy medications. It is also very stable and may be able to be inhaled or swallowed rather than injected into patients. In addition to being more convenient and less painful, this feature of the antibody may also make it less expensive than it otherwise could be.
While the research is still in the preclinical stages, the results are promising. If this antibody can prevent IgE-effector cell attachment, then the amount of IgE the body produces will not be indicative of the subsequent allergic reaction. More research will have to be conducted to determine if and how this antibody can be used to prevent allergic reactions in patients.
Many of us tend to get sick during the cold months, but if allergy symptoms arise, we are likely to blame a cold. Though rare, some people are actually allergic to the cold itself, suffering from what is known as cold urticaria. For comparison, about 1 out of every 10 people is allergic to pets, while only about 1 in 100,000 are allergic to the cold.
Cold allergies have been reported in children as young as 5 years old, but the age of onset tends to be during the adolescent years. The allergies to the cold can arise out of nowhere or may be triggered after an infection or illness. An allergy to the cold can be inherited, but inheriting this allergy is extremely rare, occurring in about 1 out of every 1 million cases of cold allergy. Many of those with cold allergies suffer from their allergies for about 5 years and then the allergy disappears.
As with many other allergies, cold allergies are diagnosed through a skin test. The patient will have an ice cube set on his or her forearm to see if changing the temperature of the skin causes an allergic reaction. The course of a cold allergy is much like that of other allergies and includes swelling, hives, and itchiness. The treatment is also the same. Patients avoid the allergen, use antihistamines, and in severe cases, deploy an EpiPen.
In extreme cases, cold can induce anaphylaxis in those who are allergic to it. Luckily for those who are allergic to the cold, allergy onset usually requires that the temperature of skin drop dramatically. By bundling up, those with cold allergies can therefore still enjoy the outdoors on cold days.
What is more dangerous for those with cold allergies than going outdoors in cold weather is swimming in cold water or eating cold foods. While swimming in cold water, cold allergy sufferers may become covered in hives –or, in severe cases, suffer from anaphylactic shock. It is particularly dangerous to suffer a severe cold allergy reaction in the water because it increases the chances of drowning. Similarly, those who have an extreme reaction eaten frozen foods or drinks may end up choking.
While cold allergies are rare, it is important to recognize when the allergy exists so that precautions can be taken to prevent symptoms or serious reactions. Those who suffer from cold allergies can generally follow the same advice as other allergy sufferers do and even rely on the same medications.
Stress adversely affects our health in a number of ways. Research has long shown that there is some relationship between stress and asthma. Much of the scientific thinking has focused on the idea that stress likely exacerbates asthma symptoms.
However, a $2.5 million long-term study at the University of Wisconsin-Madison, lead by Dr. William Busse, is exploring the idea that asthma may also exacerbate stress. As their researchers have noted, it is indeed stressful to feel as though you cannot breathe. To gain a better understanding of the association between asthma and stress, the scientists are looking both at how asthma affects the brain and at how stress affects the lungs.
First, they are inducing asthmatic events in patients and then analyzing the communication from the lungs to the brain using magnetic resonance imaging (MRI) technology. By investigating which parts of the brain are activated in response to asthma symptoms, the researchers may be able to tell whether the experience of asthma leads to a stress response.
Observing how stress may impact asthma is a more challenging task. To do so, Dr. Busse and his colleagues are placing people under stress, then inducing an asthma attack and monitoring the details of that attack.
While the study has not been completed yet, Dr. Busse suspects that what the data will show is that there is two-way communication between the lungs and the brain and that there is therefore a feedback loop that can lead to both more stress and more asthma symptoms. In other words, increased stress may exacerbate asthma symptoms, which may in turn enhance stress, and the cycle continues.
An interesting idea that Dr. Busse has is that the negative nature of the feedback between the lungs and the brain could be combatted through both medication and non-medication strategies. For instance, understanding the specific pathways and molecules involved in lung-brain communication can help with the development of medications that block problematic signaling. However, he also suggests that techniques like mindfulness and meditation may offer promising ways to modify the circuits involved in this communication.
Regardless of the specific findings of this large study, it is likely that the insights will help us better understand the link between asthma and stress. They should also inform the way we approach this link so that people under stress are less likely to experience worsening asthma symptoms and those with bad asthma are able to mitigate any potential stress responses.