Study claims "one third of people do not have asthma"

Asthma is a variable condition and there is no one test that can diagnose or rule out asthma

20th January 2017

This is according to a small Canadian study that assessed adults who had been diagnosed with asthma in the last 5 years. 

It found that after performing spirometry and (if necessary) bronchial hyper-responsiveness (BHR) testing, many patients could have their medication reduced or stopped. Patients were regularly monitored during follow up and re-tested with spirometry and BHR. The study concludes that of the 613 patients studies, 203 did not have ‘current’ asthma. Read the full study here

This has led to a number of media reports which concerned Asthma UK. Our key messages in response to this for people with asthma has been:

  • People with asthma should not stop their preventer medication on the back of this study without seeking an assessment by a clinician
  • If people are concerned they should be directed to diagnosis information on the Asthma UK website or can call our helpline nurses on 0300 222 5800

Diagnosis of asthma

Asthma is not like other long term conditions where a test is either positive or negative, or reaches a certain threshold for diagnosis. Asthma is a variable condition and there is no one test that can diagnose or rule out asthma. Because it is variable, a normal test cannot exclude asthma.

The BTS/SIGN guidelines for asthma was updated last year and highlights:

  • The importance of good history taking (symptoms, risk factors, co-morbidities)
  • Starting a trial of treatment where the history suggests a high probability of the symptoms being caused by asthma.
  • Objectively assessing the effect of treatment on symptoms, peak flow, spirometry or FeNO to come to a diagnosis.
  • Clear documentation to explain why a diagnosis was made (or not).

In the Canadian study, only 52% of study participants had evidence of their original diagnosis being confirmed by serial peak flow readings, spirometry or BHR testing. This lack of evidence spanned both generalist and specialist diagnosis.

We need all clinicians to follow asthma guidelines, especially around the diagnosis of asthma. Good documentation and explanation to the patient of any decisions around diagnosis and treatment is important to enhance understanding and adherence, and can assist with future clinical decision making.

It is also important to explain to patients the nature of asthma. Being variable means that people with asthma may go days, weeks or even years without asthma symptoms. They need to be vigilant for symptoms and seek clinical advice if they get symptoms regularly. Symptoms or reliever inhaler use three or more times per week should be considered for preventer medication.

The problem of over-diagnosis of asthma

Every so often we see reports that too many people are diagnosed with asthma. By following guidelines, documenting and explaining decisions and working with our patients we can minimise this problem. Not only are patients burdened with a diagnosis that can be scary, they will be prescribed medicines that they don’t need and that can cause harm. If they are still getting symptoms there may be another disease process that is being untreated.

If someone with asthma has well controlled symptoms for a period of at least 3 months, it may be appropriate to try to reduce their preventer medication. This should only be done after consideration of the patient’s history and pattern of disease/symptoms, and with appropriate instructions and follow up should symptoms recur.

In this study 9 people (2%) had an acute worsening of their asthma during the weaning process despite close monitoring so it is important that we give a written Asthma Action Plan including instructions on when to seek support.

What are Asthma UK doing?

Support and Advice

Asthma UK are there to provide additional support to your patients. Our website has ‘Information Standard’ education and support to supplement your normal care. This takes some of the pressure out of already-stretched appointments and means that patients do not have to remember every scrap of information that we want to share with them.

Asthma UK also have a nurse helpline which is there from 9am-5pm Monday to Friday. Feedback is very positive with 98.4% satisfaction from service users and 99.6% would recommend the helpline to others.

Social media networks

Our Facebook and Twitter accounts add a layer of support that really benefits some people with asthma. They provide self-management hints, tips, education and reminders as well as providing a supportive network. Recommend them to your patients

Research and policy

As part of our role Asthma UK is leading a call for more research to identify tests to prove or disprove asthma.

We are also highlighting and helping address the challenges posed by introducing greater levels of technology into asthma management. For example, Smart Inhalers could revolutionise self-management, encourage better adherence and allow remote monitoring of asthma symptoms to improve outcomes. If developed and implemented correctly, they could reduce the burden of asthma upon the NHS and people with asthma.