The new asthma guidelines in real world clinical practice

The new BTS/NICE/SIGN asthma guideline¹ (published in November 2024) is now more in line with GINA guidance² on the treatment of asthma, recognising that control of inflammation in the airway is the cornerstone of asthma management. The following article discusses the changes to the guidance, current recommendations for diagnosis, monitoring and management of asthma and what this means in terms of our daily practice. Our aim is cover the diagnosis, monitoring and management in a pragmatic way but also to cover some of the areas not included in the guidance but which clinicians come across every day. We are aware of a great summary of the guideline in this journal³ and also resources available on the Primary Care Respiratory Group (PCRS) website and hope that this article complements these but highlights common dilemmas for active clinicians.

DIAGNOSIS

We consider a diagnosis of asthma in people of all ages who present with symptoms that are suggestive of asthma. These symptoms are wheeze when breathing out, cough, chest tightness, and shortness of breath but not all people present with all the symptoms and a cardinal symptom of asthma is the episodic and variable nature of symptoms. However, symptoms alone are not sufficient to diagnose asthma, we need to review patient records for evidence of clinician-determined wheeze and clinically examine the patient to consider other potential causes. Not everyone who is breathless or has a cough will have asthma. (We are all aware that pleural effusions, chest infections and lung cancer can all cause many of the symptoms of asthma – and breathlessness can be caused by cardiac problems too such as atrial fibrillation and aortic stenosis).⁴ One of the fundamental parts of the new guideline is to encourage people to take an appropriate history and think carefully about the differential diagnosis. Using the new diagnostic algorithm with testing is aimed at encouraging people to focus testing when the diagnosis is being seriously considered.

Indeed some of the other causes of breathlessness on exercise or exertion are covered later in this document.

What factors in the history may guide us towards a diagnosis of asthma?

A familial history of asthma makes a diagnosis more likely in people with appropriate symptoms, as does a family history of allergy, allergic rhinitis or eczema. This is true also of people who are already known to have these problems themselves – but many people with a family history of asthma or atopy do not go on to develop asthma.

And in the examination?

Clinician-confirmed wheeze is a useful guide to this being asthma but listen carefully as the wheeze should be expiratory not inspiratory and can be generated higher up in the throat region where it suggests an alternative diagnosis. And if the airways are not constricted when someone presents, there may be no wheeze and we may have to rely on patient-reported wheeze though the reliability of this is well recognised to be weak.⁵

In practice we know that the symptoms of asthma are shared by many other conditions such as short acting beta agonist (SABA) overuse leading to hyperresponsiveness in the airways, exercise induced bronchoconstriction, breathing pattern disorder (BPD), exercise induced laryngeal obstruction, obesity, deconditioning, COPD, anaemia and also cardiac causes so we need to exclude these from our differential diagnosis by careful clinical assessment and sometimes appropriate tests.^2,4,6

Objective tests

When we have a high index of suspicion that this is asthma, we then need to undertake an objective test or tests to support our findings, and this is best undertaken before any treatment is prescribed. Clearly, if the person is acutely unwell we treat and go back to tests at a later date – but for many with stable symptoms a short period of time from arranging tests to making a robust diagnosis is the ideal. The BTS/NICE/SIGN (2024) guidance does recognise that objective testing is not always possible in the under 5s and recommends that diagnosis in this age group is based on clinical suspicion, a trial of treatment and regular review.

Order of testing: adults 16+

Blood eosinophils or Fractional exhaled Nitric Oxide (FeNO) are the first line objective tests we can undertake in practice.

Blood eosinophils are considered the first test (or FeNO if easily available) and is readily accessible if the patient has had blood tests before. The criteria ask for a value outside the normal limit from the laboratory range that you are working with (in many cases more than 0.5 x 10⁹/litre). Many of us can access previous results which are worth reviewing and considering in line with symptoms, also for most in the health service, a blood test is readily available.

We would suggest that it is always important to think about other causes of raised eosinophil levels such as allergies, infection rhinitis, dermatitis, drug allergies, ulcerative colitis, Crohn’s disease, some cancers, autoimmune disease, some drugs used in rheumatology and hereditary genetic changes.⁷

Really convenient – if you have availability – is FeNO where a simple test can provide a result within 2 minutes, which can help to support a diagnosis. NICE reviewed the literature and has suggested in adults a positive test of 50 parts per billion(ppb) can help to support the diagnosis in this age group.

However, FeNO is not definitive and can be altered by many factors such as allergic rhinitis, infection like the common cold, air pollution, medications such as antihistamines, nitrate-rich foods, age, height, HIV, cystic fibrosis, COPD, obstructive sleep apnoea (OSA) and interstitial diseases. Smoking can lower the FeNO result, as can alcohol intake, caffeine , corticosteroids and cleaning materials.⁸ Hence – like every test – the clinical context is very important. It is also recognised that many people with asthma can have a normal FeNO and eosinophil level (especially if treated, or they have a less eosinophilic type of asthma as seen in obesity and some other conditions).⁸

If the testing with eosinophil count and or FeNO is normal but clinical asthma is still suspected, the British guidelines suggest use of bronchodilator reversibility, ideally with spirometry if this is available to the clinician in a reasonable time. At the current time spirometry is not readily available in all health care settings.⁹

The guidance acknowledges problems with reversibility spirometry and recommends, if it is not available, use of peak expiratory flow rate (PEFR) variability over a 2-week period. (The older BTS/SIGN guideline recognised an important role for PEFR variability in suspected occupational asthma,¹⁰ and the authors would strongly commend clinicians to only suggest this if they are confident the patient can reliably undertake a peak flow in the surgery scenario and are committed to doing it well at home).

The guidance acknowledges that in around 50% of cases a clinician may well still be suspecting asthma despite these tests being normal. In this situation it is suggested that the patient should have a bronchial challenge test – where a substance such as methacholine, mannitol, or histamine is inhaled and irritates the airways. Lung function is measured prior to and after each dose, and the dose is increased until the airways narrow by 20% or the maximum dose is reached.

A bronchial challenge test is only available in specialist centres at the current time and again there may be a long wait for the investigation.⁹

Young people 5-16

In children and young people (CYP), the guidance suggests a slightly different order (on the basis that blood testing is less acceptable in this age group). NICE suggests first line FeNO followed – if the result is inconclusive – by bronchodilator reversibility with spirometry or PEFR variability, after which if the tests are normal and the diagnosis is still considered, blood eosinophils, total IgE and skin prick testing. A significant FeNO in this age group is lower than the adult level at >35ppb.

The background to the advice is based on a detailed 400 page analysis of the literature with modelling implications – but the guideline suggests that if, for example, the history and examination suggest asthma and the eosinophil count is raised (without a clear alternative diagnosis or reason for raised eosinophil count) the diagnosis can be made.

Children (under 5)

One of the most challenging age groups is the under 5’s, sometimes also referred to a ‘pre-school wheezers’. In this age group, tests are both difficult and unreliable, so the guidance suggests if symptoms are suggestive of asthma (and not just a episodic viral wheeze) then treatment with low dose inhaled corticosteroids and regular review is indicated.

A low dose inhaled corticosteroid in this age group is >200mcg of budesonide or its equivalent so check the equivalence before prescribing.

It is good practice to code a suspected diagnosis of asthma as just that – suspected asthma. There is considerable additional evidence arising around pre-school wheeze and this has been summarised in recent European Respiratory Society guidance – suffice it to say clinicians are already aware that this age group is challenging as so many settle down over time.¹¹

In summary, the cornerstone of a good diagnosis is a careful history and examination – along with strategic testing to support the diagnosis. However, if the diagnosis is clinically suspected but basic investigations are normal it is worth referring onto more specialist care for bronchial challenge testing.

TREATMENT

Since 1972, when the benefits of inhaled corticosteroids were first demonstrated,¹² this is the first guideline suggesting that all people with asthma – of whatever severity –should be managed with anti-inflammatory treatment as opposed to bronchodilators for some patients. What does this mean? Well, when the diagnosis is made there are two options (Figure 1).

1. Anti-inflammatory reliever (AIR) therapy using a licenced inhaled corticosteroid (ICS)/formoterol combination as required when the patient has symptoms in mild asthma. This means no requirement for a short acting beta agonist (SABA) where increasing safety concerns are becoming apparent, as highlighted in the GINA guidance around bronchial hyperresponsiveness, and higher mortality and morbidity in those using larger doses of SABA.² This is for people who have mild asthma. The British guideline is not specific about what is mild asthma – though a recent guide from the American Thoracic Society13 with European input suggests ‘Mild asthma is asthma that is characterized by minimal symptoms and risk in patients on SABA alone, as-needed ICS with SABA, as-needed ICS–formoterol, or daily ICS plus SABA or those who are not on any therapy.’

The consensus statement suggests that people with mild asthma on treatment would have:

• Daytime symptoms – fewer than two per week
• Night time symptoms – fewer than one per month
• Fewer than one exacerbation per year
• Preserved lung function.

2. The second method of treatment is Maintenance and Reliever Therapy (MART) starting a low dose inhaled corticosteroid and if necessary increasing to moderate dose prior to considering alternative medications or specialist involvement. Again there is no need for a short acting beta agonist – and patients are recommended to take regular maintenance treatment morning and night with the same inhaler being used for reliever therapy also. This treatment option was recommended previously in the 2015 NICE guidelines and the 2016 BTS/SIGN guidelines, so it is not new and well proven. There are again a variety of ICS/formoterol-based products licenced for this purpose.

Both of these treatment options have good self-management plans available on the Asthma and Lung UK website to help patients – and in both options, it is essential to prescribe an inhaler that your patient can use. The new guidance has plenty of references to the importance of inhaler technique and reviewing it prior to commencing treatment and at monitoring visits (despite recent Quality Outcome Framework suggestions that removal of checking inhaler technique is to align with the recent British Guideline, the authors can identify a whole section highlighting inhaler technique importance hence this new guidance from the Quality Outcome Framework team is baffling – and we would encourage clinicians to continue to review inhaler technique) https://www.england.nhs.uk/long-read/changes-to-the-gp-contract-in-2025-26/#annex-a-detail-of-the-changes-to-the-gp-contract-in-2025-26.

The guidance suggests that, at annual review, consider switching patients on older regimens to AIR or MART regimens, if they are happy with our explanations, as these options designed to improve outcomes for people with asthma, despite their potential cost implications. Thus those with occasional or not so occasional use of SABA inhalers can (if considered to have asthma) be converted to AIR or MART therapy (Figure 2). There are useful visual flowcharts available on the BTS/SIGN, NICE, and PCRS websites.

COMMON DILEMMAS

When should we be thinking of stepping up treatment?

And how should we ensure a SABA-free pathway for asthma treatment to manage the many people who have only ever taken SABA for their asthma, and may take some convincing of the need to take an ICS. This requires a comprehensive discussion of safety and protection of airways in the long run. Equally, it requires clinicians less familiar with asthma care to be aware that not all patients need a SABA inhaler.

Another dilemma is when to invite patients for an earlier review if they appear to be using too much of their AIR or MART. We should expect some best practice guidance from the PCRS soon – but it is worth considering that if a patient is persistently needing maximal doses of MART they should be reviewed earlier. And if a patient is using AIR more than twice daily (which would be one inhaler a month) they should certainly be considered for MART. An unknown is the number of people who use their inhaler as a placebo or psychological support – and will they continue to do so. These areas were not covered in the evidence base – but of course, in the real world this experience is harder to capture and doesn’t fit in with the usual carefully constructed trials.

Other considerations

In all age groups, we need to get the non-pharmacological matters correct. We should check smoking status including vaping and the inhalation of other respiratory irritants, any trigger factors, weight issues, exercise and lifestyle, and occupational factors.

All people diagnosed with asthma require asthma action plans and follow up and review using validated symptom tools such as the Asthma Control Test (ACT) – again we would support this in accordance with the British Asthma Guidelines.

Unlicensed medications

While in practice we may be very wary of the 2024 guidance that using ICS/formoterol in AIR therapies off-licence can be appropriate, it may just be that a particular manufacturer has not specifically tested their product in this context, so their license does not include AIR. This does not mean that it shouldn’t be considered if the inhaler device suits the needs of the patient, and they can use it with the correct inhalation technique. And always being mindful of the greener option and environmental concerns over inhaler usage is important when prescribing. Ideally, we will be following local pathways where the guidance has been adapted to fit in with local policy – but remember the adage the ‘Best inhaler is the one that the patient can and will use’ – we can help with this.

Areas not covered in the latest BTS/NICE/SIGN guidance

• Common differentials – and how to suspect or diagnose them (e.g. breathlessness in athletes and less active individuals)
• What is mild asthma?
• Management of acute exacerbations
• Primary and secondary non-pharmacological management
• Tertiary level care
• Who to refer to specialists

However, the BTS has been clear that it intends to produce and update guidance on the areas that have not been covered by the collaboration in the next few years. Meanwhile, our guidance for these issues currently dates back to 2019.¹⁰

CONCLUSION

Asthma diagnosis is not straightforward and, as we have discussed, testing may be neither straightforward nor definitive. As clinicians, we need to undertake thorough history taking and also examine our patients, and then use the tests we have available to support our diagnosis. If it doesn’t feel right, we can always review and reconsider, but the latest guidance makes our treatment safer for patients and is pragmatic in its approach. This is a chance to offer patients ‘an upgrade’ to a better, clearer diagnosis and modern treatment options based on established medicines.

REFERENCES

1. BTS, NICE, SIGN. NG245 Asthma: diagnosis, monitoring and chronic asthma management; 2024. https://www.nice.org.uk/guidance/ng245/

2. Global Initiative for Asthma (GINA). Global Strategy for Asthma Management and Prevention 2024; 2024 https://ginasthma.org/2024-report/

3. Galloway M. Guidelines in a nutshell: NICE – the final joint guidance on asthma. Practice Nurse. 2024;54(4):12-5.

4. NHS England. Adult breathlessness pathway (pre-diagnosis): diagnostic pathway support tool; 2023. https://www.england.nhs.uk/long-read/adult-breathlessness-pathway-pre-diagnosis-diagnostic-pathway-support-tool/

5. Melbye H, Garcia-Marcos L, Brand P, et al. Wheezes, crackles and rhonchi: simplifying description of lung sounds increases the agreement on their classification: a study of 12 physicians' classification of lung sounds from video recordings. BMJ Open Respiratory Research. 2016;3(1).

6. Hull JH, Burns P, Carre J, et al. BTS clinical statement for the assessment and management of respiratory problems in athletic individuals. Thorax. 2022;77(6):540-51.

7. Mejia R, Nutman TB. Evaluation and differential diagnosis of marked, persistent eosinophilia. Semin Hematol. 2012;49(2):149-59.

8. Dweik RA, Boggs PB, Erzurum SC, et al. An official ATS clinical practice guideline: interpretation of exhaled nitric oxide levels (FeNO) for clinical applications. Am J Respir Crit Care Med. 2011;184(5):602-15.

9. Asthma and Lung UK. ICS respiratory review – spirometry; 2025. https://www.asthmaandlung.org.uk/healthcare-professionals/ics-respiratory-review/spirometry

10. British Thoracic Society, Scottish Intercollegiate Guidelines Network. SIGN 158 British Guidelines for the Management of Asthma: 2019. https://www.brit-thoracic.org.uk/news/2019/btssign-british-guideline-on-the-management-of-asthma-2019/

11. Makrinioti H, Fainardi V, Bonnelykke K, et al. European Respiratory Society Statement on preschool wheezing disorders: updated definitions, knowledge gaps, and proposed future research directions. European Respiratory Journal. 2024:2400624.

12. Morrow Brown H, Storey G, George WHS. Beclomethasone Dipropionate: A New Steroid Aerosol for the Treatment of Allergic Asthma. BMJ. 1972;1(5800):585-90.

13. Mohan A, Lugogo NL, Hanania NA, et al. Questions in Mild Asthma: An Official American Thoracic Society Research Statement. Am J Respir Crit Care Med. 2023;207(11):e77-e96.

JANE SCULLION,
Independent consultant respiratory nurse, Leicester
STEVE HOLMES
General practitioner, Shepton Mallet
Practice Nurse 2025;55(2):17-21