Half a million children who have been diagnosed with asthma may not actually have the condition, The Daily Telegraph reports that new research suggests. Doctors are failing to properly assess youngsters in surgeries or carry out appropriate lung function tests which would give a definitive finding, it is claimed.
' Dr Ingrid Looijmans-van den Akker, said: "Over-diagnosis of asthma was found in more than half of the children, leading to unnecessary treatment, disease burden, and impact on their quality of life.
"Previous studies have indicated that asthma is over-diagnosed in children. However, the scale of has not been quantified.
"Only in a few children was the diagnosis of asthma confirmed using lung function tests, despite this being recommended in international guidelines. Over-diagnosis gives rise to over-prescription and incorrect use of medication, and to anxiety in parents and children."
The report says the National Institute of Clinical Excellence (Nice) said that too often doctors were basing diagnosis on case history of breathing problems, wheezing and coughs rather than any clinical tests. The watchdog is so concerned it is currently drawing up new guidelines advising doctors to use more clinical tests to back up their judgement and avoid the danger of wrongly labelling someone as asthmatic. Nice said it would be using the new report to inform its future guidance, which is expected to be published later this year.
The report says over-treatment is a concern because some of the drugs used to manage asthma can have significant side-effects including muscle cramps, throat infections, tremors, vomiting and nausea. Children with asthma often avoid exercise, which can lead to weight problems.
The best test for asthma is spirometry – which uses a machine to measure how much and how fast a person breathes out. However the Dutch new research found that a spirometer had only been used in around 16% of the cases checked. Most children were diagnosed simply because they had trouble breathing or had a persistent cough.
Dr Maureen Baker, chair of the Royal College of GPs, said: "There is no single test that can definitively diagnose asthma, and this can make it difficult to do in primary care, particularly when some common symptoms are similar to those of other illnesses.
"Some useful diagnostic tests are already available in primary care in the UK, but we need increased investment so that we can broaden GP access to this equipment and undergo the training necessary to use it in the best interests of our patients."
Dan Murphy, director of external affairs at Asthma UK, said in the report it was often difficult to diagnose athma. 'Asthma has many complex causes which is why it is very difficult to get a definitive diagnosis," he said. "It is also a highly variable condition that can change throughout someone's life or even week by week, meaning treatment also needs to change over time.
"It is vital that no parent of a child with an asthma diagnosis stops them taking their medication on the basis of this information, without discussions with their doctor."
An estimated 75% of hospital admissions for asthma are avoidable and as many as 90% of the deaths from asthma are preventable, the report said.
Background: Asthma is one of the most common chronic diseases in childhood. According to guidelines, a diagnosis of asthma should be confirmed using lung function testing in children aged >6 years. Previous studies indicate that asthma in children is probably overdiagnosed. However, the extent has not previously been assessed.
Aim: To assess the extent and characteristics of confirmed and unconfirmed diagnoses of asthma in children who were diagnosed by their GP as having asthma or who were treated as having asthma.
Design and setting: Retrospective analysis in four academic primary healthcare centres in Utrecht, the Netherlands.
Method: Routine care registration data of children aged 6–18 years who received a diagnosis of asthma or were treated as having asthma were analysed.
Results: In only 16.1% (n = 105) of the children diagnosed with asthma was the diagnosis confirmed with spirometry, whereas in 23.2% (n = 151) the signs and symptoms did give rise to suspected asthma but the children should have undergone further lung function tests. In more one-half (53.5%, n = 349) of the children the signs and symptoms made asthma unlikely and thus they were most likely overdiagnosed. The remaining 7.2% (n = 47) were probably correctly classified as not having asthma. The main reasons for classifying asthma without children undergoing further lung function tests were dyspnoea (31.9%, n = 174), cough (26.0%, n = 142), and wheezing (10.4%, n = 57).
Conclusion: Overdiagnosis of childhood asthma is common in primary care, leading to unnecessary treatment, disease burden, and impact on quality of life. However, only in a small percentage of children is a diagnosis of asthma confirmed by lung function tests.