by Anita Browning
May is Asthma Awareness Month, and members of the Children's team led by Dr. Jason Debley, an attending physician in Children's Pulmonary Division, raised $8,500 in the 2008 Puget Sound Asthma Walk.
Dr. Debley is also leading some amazing research to help diagnose asthma as soon as symptoms begin to appear in children under 3 years old. His work has been featured in Children's quarterly publication, Connection. He had just finished submitting a grant proposal to continue this work when I met with him to do this interview.
Anita: How did the grant application go?
Dr. Debley: Well, I hope! We currently have National Institutes of Health (NIH) funding for a study that follows 50 wheezy infants and toddlers through age 3. We are trying to determine if the concentration of a molecule called nitric oxide in the breath can help diagnose asthma in infants and toddlers. In this study we measure exhaled nitric oxide and lung function using specialized infant lung function testing every six months. We just submitted a new grant to secure funding to follow this group of children through age 6 years, an age at which we can more confidently diagnose asthma using currently available means.
Anita: How do you measure nitric oxide in a child's breath?
Dr. Debley: With older kids, about 6 years old and up, we can have them breathe out into a specialized analyzer at a constant rate to make the measurement. The tricky part is acquiring the same data from younger children and babies who can't control their breath. As part of this study we have developed a new method to measure exhaled nitric oxide in an infant or toddler's breath either while awake or asleep.
Anita: How do you make the measurements in infants and toddlers?
Dr. Debley: We ask parents to help. They hold the child on their lap and, while the child is distracted with a video, for example, the parent holds a mask in place over the child's nose and mouth to "catch" the breath over a 30-to-60-second period.
Anita: Why do you need that data — what does it tell you?
Dr. Debley: Comparing the levels of nitric oxide in the breath of a healthy child to the levels in the breath of a child with asthma will hopefully lead to identifying a level that tells us the patient has asthma. In our cohort of infants and toddlers with recurrent wheezing we are studying whether a child's level of exhaled nitric oxide will predict which children with outgrow their wheezing and which have early persistent asthma. To treat any condition properly, we have to know what it is. So, developing an accurate and reliable diagnostic test for asthma is really important.
Anita: Without a good way to diagnose asthma, what's happening with these wheezy infants and toddlers now?
Dr. Debley: Right now, it is common to take a "wait-and-see" approach, meaning just stand by and wait for the child to outgrow the problem. Often, that's preferable to parents who don't want to see their child take daily medicine, usually an inhaled steroid, for a condition they might not have. Even though asthma controller medications are not harmful, nobody wants to give a child a daily medication, no matter how safe, if it is not necessary.
Anita: I see. How is asthma different than the wheezing you mentioned earlier?
Dr. Debley: Recurrent wheezing is quite common, affecting at least 20% of children from birth to age 3 or 4 years. Two-thirds of these children will outgrow it by the time they start school while the other third will develop chronic asthma.
Anita: What, exactly, is asthma?
Dr. Debley: Asthma is a blockage of bronchial tubes in the lungs caused by inflammation and swelling of the bronchial tubes, and spasm of the muscles surrounding the bronchial tubes. It is a chronic condition that can develop at any time, though 80% of school-age children with asthma developed their first symptoms before age 3 years.
Anita: How big is the asthma problem?
Dr. Debley: Asthma is one of the most common chronic conditions affecting children in the country, and Washington's asthma prevalence is one of the highest in the nation. About one in ten households with children in our state has a child with asthma. It is also the leading cause of school absenteeism. At Children's we see about 500 kids each year who are hospitalized with asthma — it's the No. 1 reason for inpatient admissions.
Anita: If you are able to make a diagnosis of asthma early enough, what can you do to change the course of the condition?
Dr. Debley: There is no cure for asthma. However, a lot of asthma attacks, Emergency Department visits, hospitalizations, missed school and symptoms that prevent a child from playing can be prevented if we are able to begin the appropriate treatment and educate the family as early as possible.
Anita: Does anyone ever outgrow asthma?
Dr. Debley: Some children seem to outgrow asthma; however, long-term follow-up studies suggest that many people that seemed to outgrow asthma as children have a recurrence of symptoms later in adulthood in their forties or fifties.
Anita: What is an asthma attack?
Dr. Debley: An attack is the immune system responding to an environmental trigger, pollen, another allergen or a viral infection, for example. It causes the muscles to tighten around the bronchial tubes, and the bronchial tube lining to become swollen and filled with mucus, making it very difficult to breathe.
Anita: If allergies are also caused by environmental triggers, how is asthma different?
Dr. Debley: That's still a mystery. We don't know. Half the general population has chronic allergies, but only about 10% have asthma. There is a strong connection, though, because allergies and a family history of allergies and asthma are risk factors for developing asthma. We think there may be a difference in the cells that line the airways of asthma patients. These cells — epithelial cells — are an important interaction point between the body and the environment. We are currently studying this theory with more research at Children's comparing airway epithelial cells from patients with asthma, allergic patients and healthy patients to see how cells from these different groups of patients respond when we infect the cells with the cold virus or stimulate them with biochemicals involved in allergic inflammation.
Anita: How do you currently treat asthma?
Dr. Debley: A person with persistent asthma usually needs to take a controller, or preventative, medication every day of their life, but if the condition is managed correctly and medication taken appropriately, most patients with asthma are able to live normal lives. The controller medications are primarily inhaled steroids that reduce the inflammation of the bronchial tubes. The quick-relief medications like albuterol that patients use when they are having an asthma attack are inhalers that relax the muscles around the airway.
Anita: Is asthma life-threatening?
Dr. Debley: People do die from asthma. About 100 people per year in Washington. Unfortunately, it is usually an issue of not managing asthma with appropriate controller medications, so in many cases these deaths are preventable.
Anita: Why did you choose to focus on asthma in your career?
Dr. Debley: In pulmonary medicine in general, a lot of the conditions we deal with are chronic, which is hard for families. It's also hard for physicians. But it is possible to make a huge difference in the quality of life for these kids. It is really satisfying to watch them grow up and thrive and reach their goals. As far as the scientific aspect, making an accurate diagnosis and treating a condition properly makes a dramatic difference in a young life. Because there is no cure for asthma and no good tool to assist in diagnosing it in very young children, I am driven by my passion to change that.
Anita: Thanks so much for spending time with me!