“Current pediatric asthma guidelines do not list disability or delay as a risk factor for asthma,” says the senior study author, Sarah Messiah, PhD, the director of the Center for Pediatric Population Health at UTHealth Science Center School of Public Health in Dallas. Judging by the study results, pediatricians and specialists who care for kids with disabilities may want to consider screening for asthma, Dr. Messiah says. “If you have a child with a disability or delay and are noticing signs and symptoms of asthma in your child, ask your pediatrician for an asthma screening test,” Messiah says. “Asthma can be controlled very efficiently with medications, but a diagnosis is the first step.” Asthma is the most common chronic lung disease in children, impacting about 6 million kids in the United States, according to the Centers for Disease Control and Prevention. It can cause symptoms like wheezing, chest tightness, breathlessness, and coughing fits at night or early in the morning.
New Data Includes More Than 70,000 Children
For this study, researchers examined data on 71,811 children and teens (under age 18) whose families had participated in the 2016 and 2017 National Survey of Children’s Health (NSCH). The NSCH is a population-based, nationally representative survey; childhood asthma and disability status were reported by the parents answering the survey questions. Overall, 5,687 children (7.9 percent) had asthma and 11,426 children (15.3 percent) had one or more disabilities. Researchers included children with four broad categories of disabilities and delays: behavioral disorders (including attention deficit hyperactivity disorder [ADHD] and autism spectrum disorder); motor disabilities (including cerebral palsy and seizure disorders); vision, hearing, and speech deficits; and cognitive disabilities, including intellectual disabilities and learning disabilities. RELATED: Why Doctors Changed the Way They Categorize Autism In addition, researchers classified 3,149 children as having developmental delays, meaning they were behind on certain growth milestones and didn’t have an underlying medical condition that could explain the delay and fit neatly into one of the four broad categories above. Developmental delays are diagnosed when children don’t meet typical timelines for a wide variety of functions, such as starting to walk or talk or hold a pencil or climb stairs. Among the children with a disability, 16.1 percent had asthma, while just 6.5 percent of the children without a disability had asthma. This translated into a 2.2-fold greater risk of asthma after adjusting for other factors including age, sex, race and ethnicity, family income, and birth weight. How much each disability or delay was associated with increased asthma risk varied. Compared with kids without disabilities or delays, for example, hearing loss was associated with a more than tripled risk of asthma; and children with ADHD, cerebral palsy, or learning disabilities had a more than doubled asthma risk. RELATED: ADHD Resources and Glossary Some previous studies have linked disabilities and developmental delays to an increased risk of childhood asthma, but results have been mixed and often focused only on certain conditions, such as autism or ADHD, Messiah says. An analysis published in July 2018 in the Lancet Psychiatry that examined pooled data from 49 studies (with more than 210,000 participants with ADHD and more than 3 million people without ADHD) showed that children with ADHD were 45 percent more likely to have asthma than those without ADHD. Another study, however, published in June 2016 in PLoS One with data from 10 studies with more than 175,000 participants (including about 8,800 children with autism spectrum disorder), showed no difference in asthma prevalence between kids with and without autism.
Parent-Reported Data May Have Yielded Some Misinformation
One limitation of the study is that all the data on asthma, disabilities, and developmental delays was self-reported. It wasn’t verified by any lab tests or medical records, so it’s possible some children with these conditions were missed or that some parents incorrectly categorized their children as having conditions they didn’t have. RELATED: Choosing an Asthma Doctor: Who Are the Specialists You May Need? While all studies that rely on parent-reported diagnoses tend to misclassify some kids as having a disorder not diagnosed by a doctor, this possibility is more likely when it comes to parents reporting asthma in children with disabilities, explains Matthew McGraw, MD, an assistant professor in pediatric pulmonary medicine at the University of Rochester Medical Center in New York, who wasn’t involved in the study. Children with several types of disabilities regularly choke on foods or drinks, causing wheezing and trouble breathing that may look a lot like asthma to parents, he says. “Multiple other reasons can cause similar symptoms.” RELATED: 10 Inspiring Autism and Asperger’s Blogs to Follow Another limitation of the study is that researchers lacked data on some other important factors that can influence the risk of asthma and developmental disabilities or delays, including premature birth. “Children born premature are at higher risk for both respiratory issues and developmental delay due to underdeveloped organs such as the lungs and brain,” Dr. McGraw says. Those kids might very well still be at increased risk for being diagnosed with asthma, but it means there may be some other mediating factor that helps explain that increased risk.
More Screening for Kids With Developmental Disabilities and Delays Is Only the First Step
While the data from this new research suggest children with developmental disabilities and delays should be screened more frequently for asthma, diagnosing and managing the condition will prove to be additional hurdles to mount, according to McGraw and others. Some children with disabilities and developmental delays may not be able to understand instructions for breathing tests used to diagnose asthma, or may not be physically able to perform the tests, which means screening with existing tests may not catch every case of asthma in these children, McGraw says. (Asthma is often diagnosed using spirometry, a breathing test that measures how fast and how much air kids can blow out of their lungs.) If diagnosed with asthma, kids with certain physical or mental challenges may also struggle to recognize their symptoms or alert an adult who can help when they have breathing problems. It might be difficult for some of these children to use peak flow meters, devices that measure the rate they can force air out of their lungs, often used to determine if asthma is worsening and treatment changes are needed. “Children with disabilities may be less likely to communicate or be aware of the factors triggering their attacks, or even tell their parents when they feel their breathing is compromised,” says Luisa Borrell, DDS, PhD, a distinguished professor in the department of epidemiology and biostatistics at the CUNY Graduate School of Public Health & Health Policy in New York City. Parents may need to be even more vigilant about monitoring kids for asthma attacks. RELATED: 10 Tips to Help Your Child Manage Asthma