Breath easy

Approximately one in 15 Americans suffer from asthma and account for one-quarter of all emergency room visits in the US each year, with two million emergency room visits. The prevalence of asthma is increasing with a number of factors to blame. Dr James Li, Allergist, Immunologist and Asthma specialist at the Mayo Clinic and Dr Dave Beuther, Assistant Professor at the National Jewish Medical and Research Center, are both specialists in the field and offer their views on the huge number of asthma sufferers, potential new research and the future of asthma.

Annual economic costs to the US in direct healthcare is $11.5 billion plus indirect or lost productivity costs of $4.6 billion. Li believes this is because asthma is so common among the population that it results in decreased performance, missed days at work or school as well as caregivers being away from work. “The effect on the workplace is quite significant,” claims Li, “and direct costs are increasing as medication costs go up and hospitalization and emergency room treatment costs increase.”

Beuther agrees and goes on to say that the main way costs can be controlled is to educate patients and get them on the appropriate asthma therapy for their type of asthma. Beuther believes that the majority of asthmatics are not well controlled, and are therefore showing up for urgent office visits or at the emergency room and getting hospitalized. “If patients took their medication consistently and correctly they would do a lot better and probably cost a lot less in the long run,” comments Beuther. Li adds that patients and physicians need to recognize that their goals for asthma and aim for asthma control that results in symptom free days, no restrictions on activity, and reduced or virtually no need for rescue inhalers and understand that this can be achieving through managing and monitoring their asthma.

Obesity and asthma

New research has suggested that excess weight leads to around 250,000 new cases of asthma every year in the US. Li acknowledges that the interest in obesity links to asthma have accelerated in recent years, and says that the more it’s looked into the more there seems to be a link between increased weight and asthma. “Exactly how that association develops and whether it’s a cause and effect relationship is a little uncertain,” says Li. “I think research is showing that the link is going to be real, although how that plays out in the future is uncertain.” Li goes on to say that the common denominator from both an asthma standpoint and a general health standpoint, is that there is going to be a big push to address the obesity epidemic that’s going on in the US.

Beuther also believes there is a link between obesity and asthma. In fact, he believes that people can often be mis-diagnosed when they are obese, as many overweight people get short of breath and wheeze, and objective testing sometimes shows that they are being treated for asthma even though they don’t have it. Beuther says that many other conditions such as reflux, chronic obstructive pulmonary disease or vocal cord dysfunction can masquerade as asthma. Lung function testing is one thing that Beuther focuses on when diagnosing asthma in obese patients. “We look at reflux, nasal drainage, sleep apnea, whether there are unusual infections in the airways and how people’s bodies process these steroids and medications to see if we can understand how we may improve treatment. Then there are research protocols that we can get patients involved in,” comments Beuther.

New research

In terms of new research Li highlights the interest in combination therapy. Generally this means an inhaler with an inhaled corticosteroid and long acting bronchodilator or a combination of an inhaled corticosteroid and a short acting bronchodilator. The combination inhaler/therapy has become much more common in recent years and new products continue to be introduced to the market.

The second research area Li points to is immunomodulatory treatment of asthma. “In asthma,” he explains, “we have monoclonal anti-IGE but we don’t have a whole panoply of immunomodulatory agents. These are under development and are undergoing clinical studies – we will just have to see in the next few years how many reach the market and how effective and safe they are.”

National Jewish is also researching new methods to treat and prevent asthma and Beuther draws attention to the work they have been doing around the beta agonist receptor. This is the receptor where many medications act, and due to genetic variations, some individuals don’t get better using certain medications they actually get worse. Beuther believes that we really need to start looking at what kind of genes patients have, and based on that determining what kind of treatment they need. Beuther goes on to say that the concept of individualizing medicine is becoming increasingly important at National Jewish. “We need to individualize medicine – not every asthmatic is the same,” remarks Beuther. “They are all very different and based on those differences you may be able to predict responses to medications and then do a better job of taking care of people.”

Environmental factors

The inflammation of the lung in asthma may be as a result of an over exuberant immune system. The lung effectively has it’s own immune system and has to protect itself, most people’s lungs do a good job of that and some people’s lungs do too good a job of that, Beuther suggests that this may be asthma. Beuther also believes that it is interesting that the environment has been focused on as cause of the increasing asthma rates. “Some people have proposed that our society is too clean. That is, if you grew up on a farm or in a rural area, you are less likely to develop asthma than if you grew up in the city, where the environment may be more sterile or has fewer allergens. So there may be something about early development that predisposes to asthma,” Beuther claims.

The future

It’s not all bad news for asthma though. Within the last few years, mortality and hospitalizations due to asthma have decreased and asthma prevalence has stabilized (although figures are still extremely high). Li cites a number of factors as possible reasons why. One is that since 19991 there has been a very strong emphasis on the use of anti-inflammatory medications for asthma, and he believes that it takes around a decade for this to kick in, which is what is happening now. According to Li, there is also been an attempt on the part of experts in the field to raise awareness among patients and physicians regarding asthma similar to the success that experts have had in raising awareness of cholesterol.

Beuther believes that one reason for the stabilization is that there has been an improvement in diagnosis and appropriate treatment. “We are doing a better job at treating asthma now, we have better medications with fewer side effects, and people are taking their medications more regularly,” says Beuther.

Both Li and Beuther are optimistic about the future of asthma and as far as therapy goes Li believes that there will be a variety of new products available for asthma, including immunomodulatory agents and combination therapies. Beuther highlights the sobering studies showing that up to a third of patients aren’t in control of their asthma. He believes with improvement in treatment and compliance there is a bright future in store, “Given all that’s in the pipeline for potential asthma medications and asthma treatment, it looks like asthma has a very positive future.”