Dr. Summit Shah
It is not news that diet during pregnancy is important for the health of the growing fetus. Asthma is one condition that has been shown to occur more frequently in the offspring of those who do not eat well during pregnancy or are obese. It is perhaps therefore not surprising that a new study, performed by researchers at Harvard University and published in the Annals of American Thoracic Society, has found that the amount of sugar ingested during pregnancy could be predictive of a child’s likelihood of developing asthma.
To evaluate the impact of maternal sugar intake on a child’s risk for asthma, the researchers investigated data from 1068 Massachusetts mothers and then collected information on the diets and asthma status of their children when they were 3 and 7 years old. The researchers controlled for several non-dietary factors that could potentially lead to differences in the health of offspring, including the sex of the child, the mother’s education level, age, and smoking habits, and the body mass index and race of the mother and child.
When researchers focused on the impact of sugar, they found that the mothers who consumed the highest amounts of fructose or sugary beverages during the 1st and 2nd trimesters of their pregnancy were more likely to have children who developed asthma by the age of 7 than those who consumed the lowest amounts of sugar. They also found that children who ingested higher amounts of fructose or sugary beverages early in life were also more likely to develop asthma than those who consumed less of these sugary substances.
While these new data implicate sugar in the development of asthma, they do not provide evidence that sugar intake causes asthma. They also do not provide information on the mechanism by which sugar may lead to asthma. However, given that sugar has increasingly been shown to lead to health problems, including obesity, cardiovascular disease, and diabetes, lowering sugar intake may be a good idea, regardless of its effects on the development of asthma or other allergic conditions. Many juice and soda beverages have large quantities of sugar, and so cutting these drinks can go a long way in reducing sugar consumption.
Cluster immunotherapy is a strategy for treating allergies and allergic diseases. Like other types of immunotherapy, it is generally performed after skin tests have shown what allergies a patient has and involves a series of shots.
What makes cluster immunotherapy different from conventional therapies is the speed with which the shots are given - and how quickly a patient gets to what is known as their maintenance dose. The maintenance dose is the dose that proves most effective for treating the individual patient's allergy. Because patients get to the maintenance dose faster with cluster immunotherapy, they also often feel better faster with this approach.
While conventional immunotherapy tends to involve months of shots before the maintenance dose is reached, cluster immunotherapy can be done in a matter of hours. Some patients worry that getting several injections in a single day can increase their risk of allergic reactions. As with all immunotherapies, it is important to monitor your reaction to the therapy and to have access to the right medicine or care when undergoing cluster immunotherapy. However, it is also important to note that several studies have shown that cluster immunotherapy is a safe way to treat populations of allergy patients.
A study performed earlier this year in patients with allergic rhinitis demonstrated that cluster immunotherapy reduced the time it took for patients to get to their maintenance dose by more than 60%. The patients, who were studied over a 6 week period, experienced significant improvement in their symptoms. Critically, they did not suffer any worse systemic adverse reactions than patients who underwent conventional immunotherapy. The researchers therefore concluded that cluster immunotherapy is both safe and effective for treating certain patients.
There is ongoing research to help us understand all the advantages of cluster immunotherapy and any potential disadvantages. The research should also help to clarify which patients can benefit the most from cluster immunotherapy.
A new study conducted by scientists at the Copenhagen Studies on Asthma in Childhood Research Center in Denmark has revealed a way that cats may help protect newborns from developing asthma. According to the investigation, cats may also prevent babies from developing bronchitis and pneumonia. The researchers did not find, however, that dogs have the same impact.
Research on how pets affect the likelihood of developing allergies and asthma has produced mixed data. Some disorders appear to be more likely for those who grow up with certain pets, whereas others appear to be less likely.
A specific gene, called TT, has been implicated in the relationship between pets and the development of allergies. People with a certain genetic variant of TT have been shown to be twice as likely to develop conditions referred to as atopy conditions, which include asthma.
In this recent Danish study, the scientists studied 377 children from Denmark whose mothers had a history of asthma. The researchers analyzed the children's genes, as well as allergens collected from their beds. About 1/3 of the children carried the TT genetic variant that should have increased their risk for developing asthma.
Of these children who were genetically more susceptible to asthma, those who had a cat at home were less likely to actually develop asthma. The study did not clarify why having a cat reduces the likelihood of developing asthma, but scientists speculate that something about exposure to the cat prevents the TT gene in these children from becoming activated. Future research will likely help us understand the circumstances in which pets can protect children against allergic diseases and how exactly those pets confer their health benefits.
Adults with asthma are at increased risk for pneumococcal diseases, which are caused by the bacteria Streptococcus pneumoniae. These diseases include things like pneumonia, meningitis, and sepsis. Luckily, there are pneumococcal vaccines that can be delivered via simple injections under the skin or into the muscle that can potentially prevent these diseases.
The Centers for Disease Control and Prevention (CDC) recommends that all adults between the ages of 19 and 64 who suffer from asthma get the pneumococcal vaccine and that those older than 65 get 2 such vaccines. Nonetheless, according to a new study published in the American Journal of Preventative Medicine at the end of September, only about 50% of those with work-related asthma get the vaccine.
The study aimed to determine what percentage of people with different types of asthma actually get the pneumococcal vaccine as recommended. They were particularly interested in the difference between those with work-related asthma and those whose asthma occur independent of their work. The researchers analyzed national data from the years 2012 and 2013 and found that while overall, adults with asthma got the vaccine at a rate of about 50%. However, the likelihood of getting the vaccine varied depending on various factors. For instance, compared to those with work-related asthma, patients with asthma that was not work-related were less likely to get the pneumococcal vaccine. About 35% of those with asthma that was not work-related got the vaccine in 2012-2013.
The lowest rate of pneumococcal vaccination in work-related asthma patients was amongst Hispanics. Only about 36% of Hispanics with work-related asthma had gotten the vaccine. Uninsured patients and younger adults (ages 18-44) with work-related asthma also had low rates of vaccination, with only about 39% and 42% getting vaccinated, respectively.
Physicians and researchers are eager to get those with asthma to get the pneumococcal vaccine. The vaccination is important not only because pneumococcal diseases can be fatal (about 5-7% of the 900,000 Americans who get pneumococcal pneumonia each year die from it), but also because pneumococcal pneumonia can exacerbate asthma. Those with asthma are also at a higher risk for other complications related to pneumococcal disease.
Research like the current study that helps to reveal the actual uptake of the pneumococcal vaccine can be used to help physicians recognize the need to educate their asthma patients on the importance of the vaccine. Future studies may also be able to help clarify the best ways to increase compliance with the vaccine recommendation.
Though children with asthma are usually advised to avoid allergens that could exacerbate their symptoms, new research published in the Journal of Allergy and Clinical Immunology suggests that exposure to allergens associated with pets - and even pests - can actually prevent the development of asthma.
Dr. James Gern from the University of Wisconsin-Madison led this new study as part of an ongoing Urban Environment and Childhood Asthma study. For this particular study, Dr. Gern and his team studied 560 children living in New York City, Boston, St. Louis, and Baltimore, beginning in 2005. The children who were studied were considered at risk for developing asthma because each child had at least one parent with asthma or allergies.
When the children were aged 3 months, 2 years, and 3 years, researchers sampled allergens from their homes. They also tracked the children to determine their incidence of asthma over the first 7 years of the children's lives. They found that the higher the concentration of cockroach, mouse, and cat allergens present in these children's homes, the lower the children's risk of developing asthma by the age of 7.
Though dog allergens alone did not seem to confer any preventative benefit, when dog allergens were combined with these other allergens, the risk for developing asthma was even lower than when just cockroach, mouse, and cat allergens were present. Cockroaches appeared to be the most powerful in staving off the development of asthma.
These findings are consistent with other data suggesting that exposure to allergens can prevent the development of asthma and allergies by training the immune system to recognize these substances as harmless. These results also point to the possibility of new preventative measures for asthma. For instance, if specific allergens or bacteria can be clearly and repeatedly shown to reduce asthma risk, this knowledge can be used in the development of interventions to reduce the chances that children get the disease.
A new study, published by an Australian team in Lancet Child & Adolescent Health, has shown that an immune-based therapy has successfully allowed children who are allergic to peanuts eat peanuts for four years without experiencing reactions. The rationale for immune-based therapies is to expose children to small doses of peanut to treat their immune systems to learn that the foreign substance is not harmful and therefore to stop reacting to it as if it were threatening.
The children studied in the new research report had been enrolled in a previous study where they received a combination of probiotics and small peanut doses. Probiotics were used as a way to enable the gut to have a higher tolerance for peanuts. In this initial study, 82% of the children who received this combination therapy experienced a significant reduction in their allergic reactions to peanuts.
The new study is a follow-up study that tracks the children from the initial study four years later. According to the researchers, 67% of the children who had received the combination therapy are still comfortable eating peanuts. When tested for peanut allergy, fewer children who had received the combination therapy demonstrated allergic symptoms compared to the children who did not receive this therapy.
One criticism of this set of studies is that the scientists only compared the outcome of the allergen/probiotic combination therapy to the outcomes associated with no therapy at all. The limitation of this design is that it limits the researchers’ ability to evaluate the impact of the probiotics.
While a number of studies have shown that exposing children to allergens can improve their tolerance for that allergen. However, the evidence for the impact of probiotics on allergies is not nearly as robust. Had the researchers compared the effects of the combination therapy to those from the immune therapy alone, it would be clearer whether probiotics are beneficial in peanut allergies. Treating one group with only probiotics may make the relationship between probiotics and peanut allergies even more clear. Future research can help to clarify the importance of probiotics in fighting peanut allergies and how and why combining probiotics with immune-based therapies may enhance the benefits of immune-based therapies.
A new review published in The Lancet has revealed that older people who suffer from asthma are five times more likely to die from the condition than their younger counterparts. Unfortunately, the rate of asthma in older adults is climbing. Though the specific prevalence is debated, up to 9% of all older adults may suffer from the condition.
Why can asthma be tougher on older adults than younger adults?
For one, breathing becomes more difficult with age, even in the absence of asthma. The elasticity of the lungs diminishes as we get older, and the muscles of our respiratory systems weaken. These changes exacerbate the breathing problems that normally occur with asthma.
Another issue is that the strength of our immunes systems can decrease with age. The relevant impact is that older adults can be more likely to suffer infections that can trigger asthma attacks. Similarly, the body’s response to inflammation changes with age, so steroids that may have worked for someone with asthma in the past may stop working as they age.
According to the authors of the review, about half of older adults with asthma are not properly diagnosed, which complicates treatment and the prevention of complications. Both physicians and the patients themselves are apparently likely to blame symptoms of asthma on other conditions. For instance, people often blame their shortness of breath on being overweight or out of shape rather than considering that the symptoms represent an asthmatic condition.
Changes in cognition and motor skills are also major contributors to the heightened effects of asthma in older adults. Managing asthma requires patients to remember to take medications regularly and to deploy those medications correctly. Asthma inhalers are notoriously misused, with patients failing to get the intended doses. As patients get older and their understanding of how to use inhalers diminishes – along with their physical ability to coordinate the different aspects of using the inhalers – the chances increase that they are not getting enough medicine.
In addition to bringing more awareness to the realities of growing older with asthma and how to avoid unnecessary complications, researchers will likely aim to develop strategies to help overcome some of the challenges older adults face when dealing with asthma. Therapies that are aimed at circumventing the specific risks associated with treating asthma in the elderly could help to minimize the additional burden that asthma brings to older adults.
Though penicillin allergy is the most commonly diagnosed drug allergy, there has been mounting evidence in recent years that many people who believe they are allergic to penicillin are in fact not allergic to it. True penicillin allergy is actually quite rare.
A study that was just published in the journal Pediatrics investigated a potential penicillin allergy in 100 children between the ages of 4 and 18. The parents of all 100 children reported that their child had a penicillin allergy, but each child was deemed “low-risk” because the symptoms that led to a diagnosis were common symptoms seen in children, such as a rash. The researchers tested all 100 children for a penicillin allergy, and all 100 children tested negative.
Why are so many children who are not allergic to penicillin diagnosed as such? The answer is that penicillin allergies are often diagnosed based on clinical symptoms rather than through allergy tests. In other words, physicians will often stop a course of penicillin if a rash, itching, or vomiting occurs because these symptoms could indicate an allergy.
Because subsequent exposures to penicillin in the case of allergy can be more dangerous, the physicians will often then avoid using these antibiotics. The children (and their parents) therefore continue assuming they have a penicillin allergy without being tested.
The biggest problem with thinking that you’re allergic to penicillin when you’re not is that you will not be given penicillin or other widely used antibiotics like amoxicillin. If you get sick with an infection that would normally be treated with these antibiotics, you will instead be given something that is more likely to have adverse side effects and is also more likely to be much more expensive.
As it becomes clearer that penicillin allergy has been over-diagnosed, some physicians and researchers are recommending that penicillin allergy tests be conducted to confirm a penicillin allergy. Confirmation may be especially important in the low-risk cases, where the clinical symptoms that led to diagnosis are relatively harmless symptoms that are likely to arise from common viruses.
A study, recently published in European Respiratory Journal, investigated the potential link between pregnant women’s consumption of certain types of sugars and the development of allergy and asthma in their children. Specifically, the scientists were interested in “free sugars,” which do not include sugars found in whole fruits and vegetables.
The researchers evaluated families with children born in 1991 and 1992 and did not find any correlation between sugar intake and eczema or hay fever. They also failed to find a significant relationship between sugar consumption and asthma generally.
The researchers did, however, find that higher sugar consumption was significantly associated with allergy and the allergic form of asthma. Specifically, the 20% of mothers who ate the most sugar during pregnancy were 38% more likely to have children who developed allergies or allergic asthma than the 20% of mothers who ate the least sugar. The highest sugar intake was 82-345 grams per day, which is equivalent to 16-69 teaspoons per day. In contrast, the lowest sugar intake was less than 34 grams (or 7 teaspoons) per day.
The identified correlation between sugar intake and allergy and allergic asthma does not mean that eating more sugar during pregnancy causes allergies or allergic asthma in children. Further research needs to be conducted to determine if these findings can be replicated.
If the findings appear robust, the next step will be to determine whether sugar can actually increase the risk for allergic conditions, or if some other factor may impact both sugar intake and allergy development. Interestingly, sugar intake in children has not been shown to impact the chance of developing allergies or allergic asthma.
Researchers hypothesizing any mechanisms that could explain a causal link have pointed to lung development and suggested that high levels of fructose could cause inflammation in the developing lungs. However, this idea has not yet been tested so there are no data to confirm or deny this concept.
Doctors and scientists have long suspected a connection between asthma and diabetes, as it has appeared that people with one of these conditions tend to be at higher risk for the other. What researchers have not been clear on is the strength of the relationship and whether asthma makes it more likely to develop diabetes or vice versa.
Scientists at the National Institute for Health and Welfare in Finland have now helped to clarify the relationship between type-1 diabetes and asthma. Rather than a simple link where the presence of one condition increases the likelihood of the other, the link between diabetes and asthma is apparently more complicated. Whereas having asthma increased the risk for type-1 diabetes by about 41% in the subjects studied, having type-1 diabetes actually decreased the risk of developing asthma. The magnitude of the reduced risk for asthma was about 18%.
The researchers investigated health records from 171,138 children who were born between 1981 and 2008. From this sample, which represented 10% of the Finnish population born in that time frame, the researchers identified 80,871 children who were diagnosed with asthma and 8,939 with type-1diabetes by the age of 16. Both conditions were present in 602 of these children.
The purchase of insulin and anti-asthmatic drugs helped researchers determine children’s diagnoses. To perform their analysis, the researchers divided children into groups based on their birth years and looked at 4 age groups: 0-3, 4-7 8-11, and 12-16. The relationships between diabetes and asthma were revealed in all age groups.
While the study provided novel insights into the link between diabetes and asthma, it also contained some limitations. For one, not all the diagnoses were confirmed. Second, there was limited information on any other conditions that the patients may have had. Similarly, the researchers did not have information on when the patients developed their conditions.
The lead author of the study, Dr. Johanna Metsala, recently presented these findings at the European Academy of Allergy and Clinical Immunology Congress. The discussion at the meeting provided more insights into how scientists can further clarify the link between diabetes and asthma in the future. Researchers are particularly interested in determining whether food allergies may also be linked to diabetes.