Houston Area Pediatric Specialists

Independent pediatric specialists aim to serve our community. We want to share news and analysis regarding our specialties and our practices.

Thursday, April 25, 2013

Kids With Asthma Play Hard, Too

If you child or teenager's exercise is restricted due to asthma, it may not be adequately treated and often can be fixed.  Furthermore, the benefits of exercise on the DISEASE ITSELF may be greater than we know.  Dr. Susarla

Children with asthma should play hard in gym class and stop worrying they might have an attack that could leave them struggling to breathe, respiratory specialists are now recommending.
Physical activity by people with asthma isn't harmful and might even be helpful to treating the condition, doctors in the field believe. A report published last year in the Cochrane Database Systems Review, a journal that reviews health-care treatments and decision making, looked at 19 previous studies of exercise and asthma and concluded that people with the respiratory condition fared well with physical activity. The studies' results ranged from showing no difference in patients' asthma control to an increase in the number of symptom-free days and a decrease in asthma severity.

"If you have good, controlled asthma, you should be able to exercise," Dr. Craig says.
Laboratory studies on animals with asthma also have shown that exercise appears to reduce the severity and frequency of attacks, says Timothy Craig, an immunologist and allergist at Pennsylvania State University College of Medicine in Hershey, Pa. The experiments with mice found that exercise calms the activity of inflammatory proteins and peptides in airways that, when stimulated, cause an attack, he says.
Fear of physical activity is real for many asthma patients. Exercise can spur an attack, in which the airways get inflamed and lung muscles contract, making it hard for people to catch their breath. If untreated, serious cases can lead to death.

With nearly 1 out of 10 children having asthma, it is important to find ways for them to engage in physical activity, health officials say. Being sedentary increases the risk of obesity. Kids with asthma may struggle socially as well. Being sidelined from gym class or other group activities may make them feel isolated, and other children may see them as fragile and a target for teasing.
Asthma affects about 9% of children in the U.S. under the age of 17, and for many the condition is lifelong. Overall, more than 25 million Americans of all ages have asthma, representing about 8.4% of the population in 2010, up from 7.3% in 2001, according to data from the Centers for Disease Control and Prevention.


When exercise leads to frequent asthma attacks, it is a sign the asthma isn't well controlled and that a better treatment plan is needed, Dr. Craig says. In most of these cases, both the physicians and patients have underestimated the asthma, he says. Patients may then become frustrated and anxious and abandon efforts to exercise, he says.
Celia Vigil, a 12-year-old in Spokane, Wash., avoided strenuous exercise for years for fear of an asthma attack. When she did participate in school sports, she says she usually didn't get very far and often had to be pulled quickly out of a game. An asthma flare-up left her feeling like she couldn't get enough air. "It feels scary," she says. "You don't know when you'll get out of it."

Even when people with asthma have a good treatment plan in place, they need to take extra precautions while exercising, Dr. Craig says. Patients should warm up before walking or jogging, for example, by starting at a slower pace. They also should "warm down" afterward by reducing speed or exertion before stopping completely. Changing one's heart rate gradually appears to lower the risk of an attack, Dr. Craig says.
Two years ago, Celia started seeing a new doctor who talks about the importance of exercise at each visit. She switched to a longer-acting medication, Advair, that better controls her symptoms. And she sometimes takes two puffs on her inhaler before exercising, which she wasn't doing before. Now, Celia says, she is able mostly to keep up with the other kids in gym class. "It's more fun to participate," she says.  "I've come really far."

Saturday, April 20, 2013

Advanced Lung Function Testing in Children/Adolescents With Asthma

A major problem in pediatric asthma is getting objective, reliable data about how a child's lungs function.  Much of the testing available in children requires exceptional breathing efforts that force a child's lungs to perform in a somewhat artificial way.  These tests include spirometry, a highly researched and standardized test that is used to assess asthma control.  However, it is often difficult to perform in young children, fails to properly identify "small airways disease" in many cases, and is often too insensitive to diagnose asthma in some children.  Impulse oscillometry offers a solution to these problems by providing an effort independent, highly sensitive and reproducible test which can be performed in very young children (often as young as 3 years).  Moreover, it is the test of choice to identify the location of the problem in many children with asthma  --  the "small airways".  A growing body of research including the reference below suggest that impulse oscillometry (IOS) should have greater use in a pediatric asthma practice.  Dr. Susarla

Peripheral airway impairment measured by oscillometry predicts loss of asthma control in children.


Department of Biomedical Engineering, University of California, Irvine, Calif.



We previously showed that impulse oscillometry (IOS) indices of peripheral airway function are associated with asthma control inchildren. However, little data exist on whether dysfunction in the peripheral airways can predict loss of asthma control.


We sought to determine the utility of peripheral airway impairment, as measured by IOS, in predicting loss of asthma control inchildren.


Fifty-four children (age, 7-17 years) with controlled asthma were enrolled in the study. Spirometric and IOS indices of airway function were obtained at baseline and at a follow-up visit 8 to 12 weeks later. Physicians who were blinded to the IOS measurements assessed asthma control (National Asthma Education and Prevention Program guidelines) on both visits and prescribed no medication change between visits.


Thirty-eight (70%) patients maintained asthma control between 2 visits (group C-C), and 16 patients had asthma that became uncontrolled on the follow-up visit (group C-UC). There was no difference in baseline spirometric results between the C-C and C-UC groups, except for FEV(1)/forced vital capacity ratio (86% vs 82%, respectively; P < .01). Baseline IOS results, including resistance of the respiratory system at 5 Hz (R5; 6.4 vs 4.3 cm H(2)O · L(-1) · s), frequency dependence of resistance (difference of R5 and resistance of the respiratory system at 20 Hz [R5-20]; 2.0 vs 0.7 cm H(2)O · L(-1) · s), and reactance area (13.1 vs 4.1 cm H(2)O · L(-1)), of group C-UC were significantly higher than those of group C-C (P < .01). Receiver operating characteristic analysis showed baseline R5-20 and reactance area effectively predicted asthma control status at the follow-up visit (area under the curve, 0.91 and 0.90).


Children with controlled asthma who have increased peripheral airway IOS indices are at risk of losing asthma control.
 2012 Nov 10. pii: S0091-6749(12)01544-8. doi: 10.1016/j.jaci.2012.09.022.

Monday, April 15, 2013

Impulse Oscillometry Offers Hope of Early Diagnosis of Asthma

Impulse oscillometry is an advanced lung function testing method that allows early asthma diagnosis and better prediction in loss of asthma control.  Dr Susarla

Impulse Oscillometry Offers Hope of Early Diagnosis of Asthma

A study led by researchers at NIAID suggests that impulse oscillometry (IOS), a non-invasive method for measuring lung function, is more effective in detecting asthma in children than spirometry, the commonly used method. The results appear in the August 2011 issue of Pediatric Pulmonology.


A child uses an IOS machine to measure lung function. Credit: NIAID
Jason1 was only 3 years old when he first arrived at the Pediatric Allergy Clinic at the National Institutes of Health (NIH), in Bethesda, Maryland. He had a history of severe allergic reactions to food and suffered from chronic atopic dermatitis, also called eczema. Recently, he had developed recurrent coughing and wheezing. His doctor suspected asthma and prescribed daily use of inhaled corticosteroids.
Before adding another drug to Jason’s daily regimen, his parents wanted conclusive proof that he had asthma. The standard test used to diagnose asthma, called spirometry, requires that a person exhale vigorously into a machine for 10 to 15 seconds. As a result, younger children and some adults with physical impairment may not be able to use the test. Because of Jason’s age, he would have to wait two to three years before he could take a lung function test to confirm his doctor’s diagnosis.
“A challenge for clinicians is how to make an accurate diagnosis in cases when the patient is not capable of performing the test required for that diagnosis,” said Hirsh D. Komarow, M.D., of the NIAID Laboratory of Allergic Diseases.

New Technology

IOS is a newer method of measuring lung function that has gradually been gaining acceptance by clinicians. The IOS machine works by producing small-pressure oscillations (vibrations) that are applied at the mouth and transmitted into the lungs. Measuring how the respiratory system responds to these impulses during natural breathing provides an indirect analysis of lung function. Unlike spirometry, IOS is non-invasive and easy-to-perform and requires minimal assistance from the patient.
“IOS offers several advantages over spirometry in the evaluation of young children in clinical practice,” said Dr. Komarow, “We sought to answer the question: Are the test results obtained from IOS as accurate as those produced by spirometry.”

Study Results and Significance

Dr. Komarow’s study compared results from lung function tests measured by IOS and by spirometry in 117 children who already were receiving medical care at the NIH Pediatric Allergy Clinic.
“The data were conclusive,” said Dean Metcalfe, M.D., chief of the Laboratory of Allergic Diseases, “In these children, IOS was not only more sensitive than spirometry, it was more specific in identifying children with asthma.”
This is a promising advance in asthma care. Asthma is a chronic lung disease that affects more than 22 million people in the United States, including nearly 7 million children under age 6. Early diagnosis of asthma promises several benefits: parents are able to more closely monitor their child for respiratory symptoms that may worsen asthma; doctors can track the course of the disease over a longer time period to better predict its outcome; and there are studies that indicate that beginning asthma treatment at a younger age improves long-term control of the illness.
Dr. Komarow examined Jason using IOS and in moments confirmed that Jason had asthma.
“I was pleased that Jason could be evaluated with IOS at the clinic,” said Dr. Komarow, “We made an objective diagnosis and he is receiving appropriate treatment to manage his asthma. This would not have been possible without IOS.”

Read article here.

Wednesday, April 3, 2013

Genetic Variants and Wheezing Put Kids At Risk For Asthma

Adding to the state of asthma research in children, there appear to be specific genes that confer risk of wheezing in children possibly portending risk of asthma as well.  Dr. Susarla

Genetic Variants and Wheezing Put Kids At Risk For Asthma

Almost every toddler will sniffle through a cold by the time they are three, but if they wheeze while they’re sick, they may be at higher risk of developing asthma.

Previous research found that wheezing-related illnesses can increase a child’s risk for developing asthma, and other studies connected certain genetic factors to this heightened tendency to wheeze. In a new study published in the New England Journal of Medicine, researchers connected the two and found that 90% of three-year-olds with a combination of specific genes and a particular wheezing illness were diagnosed with asthma by the age of 6.
The scientists focused on a region of chromosome 17, known as 17q21 that has been associated with an elevated risk of asthma early in life. Two genes in the region likely increase this risk — ORMDL3 and GSDMB. Variants of these genes, which are relatively common, seemed to confer higher risk of wheezing when children were infected with the rhinovirus, which is responsible for the common cold. About half of the infants in the study had one copy of the variant, while a quarter had both copies, which significantly increased their likelihood of wheezing and developing asthma.
The researchers included children from two separate study groups, all of whom came from families with a history of allergies or asthma. The first group included 200 children toddlers with at least one, and possibly two parents who had allergies or asthma while the second group consisted of Danish toddlers whose mothers were diagnosed with asthma. Among children without the high-risk genetic variants for asthma, 40% who wheezed when they caught a cold before age three developed asthma by age six, compared to 60% who had one copy of the variant and wheezed, and 90% of those who had two copies and also wheezed.
“We found that the interaction between this specific wheezing illness and a gene or genes on a region of chromosome 17 determines childhood asthma risk. The combination of genetic predisposition and the child’s response to this infection has a huge effect,” said study author Carole Ober, a Blum-Riese Professor of Human Genetics at the University of Chicago in a statement.
Overall, the children with the genetic and wheezing illness combination were almost four times as likely to develop asthma compared to kids who did not have the genetic variation or did not wheeze, suggesting that wheezing might be a relatively easy marker for identifying toddlers who might be at highest risk of developing asthma later.
The biological mechanisms underlying the connection are not well understood, but to get a better idea of what’s going on, the researchers collected blood from 100 healthy adults and exposed their immune cells to human rhinovirus. Infection with the cold virus seemed to make the asthma-related genes on chromosome 17 more active, possibly leading to more wheezing.
If the results are confirmed, then doctors and parents could be more alert to early signs of wheezing, and consider testing for the presence of the genetic variants that could increase the risk of asthma. Such early intervention could help to limit exposure to asthma triggers, such as cigarette smokebisphenol A and other potential irritants, and hopefully reduce the severest symptoms as well.
Read article here.