According to the Center for Disease Control, 1 in 12 Americans have asthma and that number is on the rise. In the ten year span between 2001 to 2011, 28% more patients were diagnosed with the respiratory disease. Each year, an estimated 1.6 million people visit the ER with asthma as the primary diagnosis. But a new study has found that 1 in 3 patients diagnosed with asthma may not actually have the condition.
The study
Canadian researchers recruited 613 men and women to participate in a study. Everyone in the group had been given an asthma diagnosis sometime within the last 5 years. Eighty percent of the study participants were taking asthma drugs like Singulair and Flovent and 35% of those patients were taking these medications on a daily basis.
Over a series of 4 visits, the scientists gave the participants several drug challenges to confirm or rule out an asthma diagnosis. One of the tests included a spirometry, which accesses how well a patient’s lungs work by measuring how much air they inhale, how much they exhale, and how quickly they exhale.
The findings
The respiratory experts behind the study found that 213 people, aka 1/3 of the group members, did not actually have asthma. Of those who were wrongly diagnosed, 90% were able to stop their asthma management medications completely and were completely fine after doing so for over a year. Many of these patients had minor conditions like allergies or heartburn instead of asthma and 28% had nothing wrong with them at all. The researchers noted that in about 2% of the cases, the patients were diagnosed based on symptoms alone and not clinical testing.
The study’s lead researcher, Dr. Shawn D. Aaron, a professor at the University of Ottawa, has a couple theories on why 1/3 of its participants were incorrectly diagnosed with asthma. “Firstly, some patients were misdiagnosed in the community – meaning they never had asthma to begin with. Secondly, some had asthma, but it was inactive – meaning it was in remission,” he explains.
What does this mean?
The study authors concluded that: “Among adults with physician-diagnosed asthma, a current diagnosis of asthma could not be established in 33.1% who were not using daily asthma medications or had medications weaned. In patients such as these, reassessing the asthma diagnosis may be warranted.” In other words, if you have been diagnosed with asthma in the past, it can be beneficial to regularly reevaluate your symptoms with a doctor.
And if you suspect that you may have asthma and have not yet been diagnosed, it’s crucial that you go in for the correct testing to verify your diagnosis. It’s also important not to start a dosage of asthma medication before the results of the testing confirm your diagnosis. Dr. Aaron advised the New York Times that symptoms such as a cough or wheeze should not be enough to diagnosis a person as asthmatic or to put them on steroid inhalers. “If you have shortness of breath, wheeze or cough, you should suggest that the doctor order a spirometry test,” he said. “It’s a quick test with no risks or side effects that can predict asthma or other respiratory conditions,” he explained.
“This study underscores the possibility of over-diagnosis of asthma, and the importance of careful testing of pulmonary [lung] function to make a clear diagnosis before committing a patient to lifelong treatment,” adds Dr. Brian Christman, a spokesman for the American Lung Association.
The National Heart, Lung, and Blood Institute recommends the following types of tests to correctly diagnosis asthma:
