By Steven Reinberg
According to a survey of more than 33,000 New York City high school students, 20 percent reported having asthma-like symptoms, but were not diagnosed with the illness.
The researchers also found that teenage girls and Asian-Americans were more likely to have undiagnosed asthma.
"Potentially, there are a lot of these kids out there who are undiagnosed," said lead researcher Sharon Kingston. She is an associate professor of psychology at Dickinson College in Carlisle, Pa.
"There is a need for more public health education and outreach, not only for adolescents and their families, but also for health care providers who could screen adolescents for asthma," she said in a college news release.
In people with asthma, their airways become inflamed. This causes the airway to narrow and swell and make extra mucus, making it difficult to breathe.
Asthma is the most common chronic illness among children, and it can lead to school absences, reduced physical activity and quality of life, and the need for health care services.
Earlier studies have shown that 8 percent to 49 percent of kids aged 7 to 18 with asthma symptoms were not diagnosed.
In teens, undiagnosed asthma is especially problematic, Kingston said. That's because they are less likely to see a doctor for routine care, which may reduce their odds of being diagnosed.
The report was published Jan. 2 in the Journal of Public Health.