Kids being misdiagnosed with asthma, experts say
Improper testing said to be factor: ‘It’s a huge issue,’ says respirologist
Adults are not the only ones being wrongly diagnosed with asthma — overdiagnosis is also a serious problem for children, says the head of respirology at the Children’s Hospital of Eastern Ontario.
“We say routinely that asthma has gone from being chronically underdiagnosed to being misdiagnosed and overdiagnosed,” said Dr. Ian MacLusky, chief respirologist at CHEO.
Asthma is a common problem for children, according to the Asthma Society of Canada, which says it affects at least 13 per cent of Canadian children and is a major cause of hospitalization.
“It is a huge issue,” said MacLusky, who added that asthma is “one of the commonest reasons during viral season for children to be lined up in emergency.”
This week, research by Dr. Shawn Aaron, senior scientist and respirologist at The Ottawa Hospital and professor at the University of Ottawa, made headlines around the world. Aaron’s research, published in the Journal of the American Medical Association, found that 33 per cent of adults recently diagnosed with asthma did not have it. More than 90 per cent of those patients studied and found not to have asthma were able to stop taking their medication.
Aaron noted many of the patients had originally been diagnosed based on their symptoms and their physicians’ observations, rather than being given a spirometry test, which is considered the gold standard to diagnose asthma.
Spirometry is a test that can be done in a physician’s office. It assesses how well a patient’s lungs work and can diagnose asthma, chronic obstructive pulmonary disease (COPD) and other conditions that affect breathing.
“Doctors wouldn’t diagnose diabetes without checking blood sugar levels, or a broken bone without ordering an X-ray,” said Aaron.
“But for some reason many doctors are not ordering the spirometry tests that can definitely diagnose asthma.”
Research on overdiagnosis of asthma in children has not been as extensive as Aaron’s most recent study, which looked at 613 randomly selected patients from 10 Canadian cities diagnosed with asthma in the last five years.
One Dutch retrospective study published last year concluded that overdiagnosis of childhood asthma is common in primary care, leading to unnecessary treatment and impact on quality of life.
The research also concluded that asthma was only confirmed with lung function tests in a small percentage of the children who were diagnosed.
Children under six cannot be given spirometry tests, which can make diagnosis more difficult.
And MacLusky said asthma can, in general, be difficult to diagnose.
“It is not simple. There is not a genetic test, there is not a blood test.”
But, still, MacLusky said often diagnoses are made quickly and not using testing, even when it can be done.
And while some studies have found that children are also being wrongly diagnosed — one found only eight per cent of children diagnosed with exercise-induced asthma actually had it — diagnoses are still being missed in other cases, he said.
“It used to be underdiagnosed. Now it is the worst of both worlds. It is still underdiagnosed and also overdiagnosed. We still see kids
It is a huge issue — one of the commonest reasons during viral season for children to be lined up in emergency.
with recurrent bronchitis that turns out to be asthma.”
Meanwhile, Aaron, whose most recent study confirms earlier findings that 30 per cent of asthma patients had been misdiagnosed, said it is crucial to get the diagnosis right in the first place, and that includes ordering a spirometry test to determine if the patient might have asthma or even chronic obstructive pulmonary disease.
Carole Madeley of the Ontario Lung Association said it offers workshops and trainings on spirometry testing to encourage physicians to use the device and properly diagnose patients.
Patients who think they might have been misdiagnosed with asthma are being encouraged to ask their doctor for a spirometry test. epayne@postmedia.com