Worsening symptoms cost $50 billion in health-care costs each year
Children with asthma tend to experience worse symptoms at the same times every year: when school starts in the fall and after spring or Easter break.
Researchers previously attributed the problem to environmental factors, such as air quality in schools, but a recent study cites the common cold as the main culprit of seasonal waves of worsening asthma symptoms, which can lead to hospitalizations.
Exacerbations, the medical term for worsening asthma symptoms, cause millions of missed work and school days and cost $50 billion in direct health-care costs in the United States each year, according to researchers.
“This work can improve public health strategies to keep asthmatic children healthy,” said Lauren Meyers, professor of integrative biology and statistics and data sciences at the University of Texas at Austin. “For example, at the riskiest times of year, doctors could encourage patient adherence to preventive medications, and schools could take measures to reduce cold transmission.”
Earlier studies looking into the cause of exacerbations involved swabbing individual patients to detect viruses, but Meyers, a mathematical biologist, and her team studied population-wide patterns of how common colds circulate among adults and children throughout the year to learn about the role of the viruses.
The researchers then built a computer model incorporating possible drivers of asthma exacerbations and compared the output of the model to a large set of real-world health data: the timing and locations of about 66,000 asthma hospitalizations from cities across Texas over a seven-year period. The findings show the spread of cold viruses, which is heavily influenced by the school calendar, is the primary driver of asthma exacerbations.
“The school calendar predicts common cold transmission, and the common cold predicts asthma exacerbations,” Meyers said.
When children are out of school, the authors speculated, they tend to spend less time with other children and are exposed to fewer viruses. As a result, their viral immunity decreases. When school is back in session, they are exposed to viruses at much higher rates, and this is also the time when they are most susceptible.
[Also read: Children With Allergies at Increased Risk of Early Heart Disease]
The study also developed more accurate rates of transmission of cold viruses than have been produced by previous studies—information that might help shed light on how common colds spread, and how we can protect people who are most vulnerable to them.
Asthma, a chronic inflammatory disease of the airways, affects nearly 7 million children in this country, according to the Centers for Disease Control and Prevention, and the numbers are rising. Black children are 3.6 times more likely to visit the emergency room for asthma symptoms, and they have a death rate seven times that of white children.