Introduction
Conclusion
References

 

 

 

 

 

Introduction

Asthma is a common lung condition that causes breathing problems. The airways become inflamed and narrow, causing breathlessness, coughing, wheezing and tightness in the chest.1

Asthma UK estimates that around 4.5 million people in England are receiving treatment for asthma.

In new guidance entitled Asthma: diagnosis, monitoring and chronic asthma management released recently, NICE state that new tests to help diagnose the condition and a change in how medicines are offered can help people take control of their asthma.


Tests

NICE is recommending objective tests that include spirometry and fractional exhaled nitric oxide (FeNO), to help confirm a diagnosis of asthma. This can achieve more accurate diagnosis and therefore more effective treatment, according to NICE.

Spirometry tests assess how well someone’s lungs work by measuring how much air they inhale and exhale, and how quickly.

FeNO tests measure the levels of nitric oxide in the breath. Increased levels are thought to be related to lung inflammation and asthma. NICE caution that a person’s current smoking status can lower FeNO levels both acutely and cumulatively. However, a high level remains useful in supporting a diagnosis of asthma.


Initial clinical assessment

The guidance recommends that physicians take a structured clinical history in people with suspected asthma to specifically, check for:

  • Wheeze, cough or breathlessness, and any daily or seasonal variation in these symptoms
  • Any triggers that make symptoms worse
  • A personal or family history of atopic disorders.

Patients with suspected asthma should be examined to identify expiratory polyphonic wheeze and signs of other causes of respiratory symptoms, but to be aware that even if examination results are normal the person may still have asthma.

People should be treated immediately if they are acutely unwell at presentation, and objective tests for asthma performed (for example, FeNO, spirometry and peak flow variability) if the equipment is available and testing will not compromise treatment of the acute episode.

If objective tests for asthma cannot be done immediately for people who are acutely unwell at presentation, they should be carried out when acute symptoms have been controlled, and patients are advised to contact their healthcare professional immediately if they become unwell while waiting to have objective tests.

When testing for asthma, the following diagnostic tests should not be offered: skin prick tests to aeroallergens, serum total and specific IgE, peripheral blood eosinophil count and exercise challenge (to adults aged 17 and over).

Skin prick tests to aeroallergens or specific IgE tests to identify triggers should only be used after a formal diagnosis of asthma has been made.


Diagnosis

The guidance says that a diagnosis of asthma can be made in adults over the age of 17 if they have symptoms suggestive of asthma and:

  • A FeNO level of 40ppb or more with either positive bronchodilator reversibility or positive peak flow variability or bronchial hyperreactivity, or
  • A FeNO level between 25 and 39ppb and a positive bronchial challenge test, or
  • Positive bronchodilator reversibility and positive peak flow variability irrespective of FeNO level.

Professor Mark Baker, Director of the Centre for Guidelines at NICE, said: “We are recommending objective testing with spirometry and FeNO for most people with suspected asthma; a significant enhancement to current practice, which will take the NHS some time to implement, with additional infrastructure and training needed in primary care.

“New models of care, being developed locally, could offer the opportunity to implement these recommendations. This may involve establishing diagnostic hubs to make testing efficient and affordable. They will be able to draw on the positive experience of NICE’s primary care pilot sites, which trialled the use of FeNO.”

He added that the investment and training required to implement the new guidance will take time. In the meantime, primary care services should implement what they can of the new guidelines, using currently available approaches to diagnosis until the infrastructure for objective testing is in place.”

Dr Andrew Menzies-Gow, consultant in respiratory medicine at the Royal Brompton and Harefield NHS Foundation Trust and co-chair of the guideline committee, said: “Our recommendations will help tackle inappropriate diagnosis and ensure that if a diagnosis is given, that the person is monitored to ensure their symptoms still indicate asthma.”


Principles of pharmacological treatment

Physicians are recommended to take into account the possible reasons for uncontrolled asthma before starting or adjusting medicines for asthma in adults, young people and children. These may include:

  • Alternative diagnoses
  • Lack of adherence
  • Suboptimal inhaler technique
  • Smoking (active or passive)
  • Occupational exposures
  • Psychosocial factors
  • Seasonal or environmental factors.


Treatment

NICE is also recommending people with poorly controlled asthma be offered a tablet to be taken with a preventer inhaler before other, more expensive treatments are considered.

When preventer inhalers are no longer helping people gain good control of their symptoms, they are currently offered a long acting beta-agonist (LABA) with a low-dose inhaled corticosteroid; the treatment found in a preventer inhaler.

This is often given in a combination inhaler, which comes in pink, red, yellow, purple or grey, or in two separate devices. However, NICE now recommends they take a leukotriene receptor antagonist (LTRA) tablet before treatment with LABA.

This change in the way treatment is offered could save the NHS an estimated £2million a year for every 10,000 people who take up the new recommendation, according to NICE.

 

BOX 1: POSITIVE TEST THRESHOLDS FOR OBJECTIVE TESTS FOR ADULTS, YOUNG PEOPLE AND CHILDREN (AGED 5 AND OVER)
Test Population Positive result
FeNO Adults 40ppb or more
Children and young people 35ppb or more
Obstructive spirometry Adults, young people and children FEV1/FVC ratio less than 70% (or below the lower limit of normal if this value is available)
Bronchodilator reversibility (BDR) test Adults Improvement in FEV1 of 12% or more and increase in volume of 200 ml or more
Children and young people Improvement in FEV1 of 12% or more
Peak flow variability Adults, young people and children Variability over 20%
Direct bronchial challenge test with histamine or methacholine Adults PC20 of 8mg/ml or less
Children and young people n/a
Abbreviations: FeNO, fractional exhaled nitric oxide; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; PC20, provocative concentration of methacholine causing a 20% fall in FEV1.


Key treatment recommendations

A short-acting beta2 agonist (SABA) as reliever therapy should be offered to adults (aged 17 and over) with newly diagnosed asthma. Those with asthma who have infrequent, short-lived wheeze and normal lung function, should consider treatment with SABA reliever therapy alone.

A low dose of an inhaled corticosteroids (ICS) should be offered as the first-line maintenance therapy to adults with:

  • Symptoms at presentation that clearly indicate the need for maintenance therapy (for example, asthmarelated symptoms three times a week or more, or causing waking at night) or
  • Asthma that is uncontrolled with a SABA alone.

If asthma is uncontrolled in adults on a low dose of ICS as maintenance therapy, offer a LTRA in addition to the ICS and review the response to treatment in four to eight weeks. If asthma is uncontrolled in adults on a low dose of ICS and an LTRA as maintenance therapy, offer a LABA in combination with the ICS, and review LTRA treatment as follows:

  • Discuss with the person whether or not to continue LTRA treatment
  • Take into account the degree of response to LTRA treatment.

If asthma is uncontrolled in adults on a low dose of ICS and a LABA, with or without an LTRA, as maintenance therapy, offer to change the person’s ICS and LABA maintenance therapy to a maintenance and reliever therapy (MART) regimen with a low maintenance ICS dose.

If asthma is uncontrolled in adults on a MART regimen with a low maintenance ICS dose, with or without an LTRA, consider increasing the ICS to a moderate maintenance dose (either continuing on a MART regimen or changing to a fixed-dose of an ICS and a LABA, with a SABA as a reliever therapy).

In those on a moderate maintenance ICS dose with a LABA (either as MART or a fixed-dose regimen), with or without an LTRA, consider:

  • Increasing the ICS to a high maintenance dose (this should only be offered as part of a fixeddose regimen, with a SABA used as a reliever therapy)
  • A trial of an additional drug (for example, a long-acting muscarinic receptor antagonist or theophylline)
  • Seeking advice from a healthcare professional with expertise in asthma.

 

Conclusion

The key difference in the new guidance is that diagnostic tests now need to be carried out before giving treatment. The combination of spirometry, FeNO and peak flow testing will help rule out asthma before a treatment plan is drawn up.

Although management largely remains the same, the biggest change is that NICE now recommends a new approach for patients who are not controlled on medication. They will now be offered a LTRA to take alongside the preventer inhaler for four to eight weeks to see if it makes a difference. LTRA was viewed by NICE to be more cost-effective than a combination inhaler.

 

References

1. NICE. Asthma: diagnosis, monitoring and chronic asthma management 2017. https://www.nice.org.uk/guidance/ng80 (acessed December 2017)