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holmes steve

Guest Editor—Dr Steve Holmes

GP, Park Medical Practice, Shepton Mallet 

The latest update to the BTS/SIGN British guideline on the management of asthma was issued in 2016 and provides guidance that is supported by high-quality global evidence and data. This email considers the key changes to the guideline and provides practical tips and advice on how to implement the recommendations in primary care.

The first British guideline on the management of asthma was published in 1990 by the British Thoracic Society (BTS).1

By 1999 BTS and the Scottish Intercollegiate Guidelines Network (SIGN) had agreed to publish joint, comprehensive guidance on the management of asthma using evidence-based methodology and also recognising the important role of multidisciplinary teams (working across primary, secondary, and tertiary care) and patients in the guideline development process.2

The latest update, published in 2016, has remained true to these principles; providing guidance that is supported by high-quality, peer-reviewed global evidence and data.2

Key areas that differ from previous guidelines are detailed in Box 1. Each of these areas are discussed briefly below, and further detail can be obtained from the full guidance document, which provides the evidence supporting each of the recommendations.2

Key areas that differ from previous BTS/SIGN guidance on asthma management2

  1. Diagnosing asthma—explanation of the best approaches for accurate diagnosis
  2. Documenting an asthma diagnosis—suggested methods for documenting asthma diagnosis
  3. Increasing and reducing treatment over time—no more steps
  4. Specialist referral—prompts for when to seek the opinion of a respiratory expert.

1. Diagnosing asthma

An accurate asthma diagnosis is really important for our patients, especially as there is no simple diagnostic test for asthma (unlike other chronic conditions such as diabetes and hypertension).3,4

The guideline recommends approaches to diagnosis based on whether there is a high, moderate, or low probability of the patient having asthma.2

High probability

If we believe that a patient has a high probability of asthma, we should record a diagnosis of ‘suspected asthma’, treat appropriately, and then review.

The probability of asthma is high when there is:2

  • a confirmed history—symptoms of wheeze, cough, breathlessness, and chest tightness that vary over time  alongside
  • other factors—associated atopy (or family history), a clear relationship of symptoms with triggers such as exercise) and
  • compatible documented findings confirmed by further testing—evidence of peak expiratory flow rate (PEFR) variability or prolonged expiratory wheeze heard on auscultation.

This means that if we see a patient with a confirmed history and possible examination findings the next step is to find evidence of airway inflammation and reversibility.

Initiate treatment and monitor for response

People with asthma tend to respond to treatment. Hence, the next stage recommended is to initiate treatment and monitor for a response. For patients with a high probability of asthma, the guidance suggests a trial of low dose inhaled corticosteroid (ICS) for around 6 weeks.2 However, if the patient has acute symptoms on presentation, a review after 7–14 days of oral corticosteroid treatment (40–50 mg for an adult) would be reasonable.

If the patient responds well to ICS treatment and shows evidence of airway improvement (demonstrated by PEFR measurement/spirometry) with symptomatic recovery, assessed using a validated tool such as the asthma control test (ACT), we can confidently make an asthma diagnosis (see Documenting a diagnosis below).

Finding evidence of airway inflammation and reversibility2

If clinical assessment and other documented findings (e.g. prolonged expiratory wheeze heard on ausculation) suggest high probability of asthma confirm by further testing:

  • airway inflammation—identify airway inflammation, based on either a high eosinophil count or FeNO
  • evidence of reversibility, proven either by spirometry or a change in PEFR after treatment—this is complex as patients receiving asthma treatment may have normal spirometry results or their condition may be quiescent at the time of clinical assessment.

FeNO=fractional exhaled nitric oxide; PEFR=peak expiratory flow rate

Intermediate probability

If we are unsure of the diagnosis from the evidence presented, but believe there is a reasonable possibility that the patient may have asthma, then we should review the clinical history and spirometry or PEFR results alongside FeNO tests.2

If FeNO testing facilities are not available this procedure may be performed by colleagues in specialist care.2 Serum eosinophil tests may also provide evidence of inflammation.2 If we feel confident, then we should investigate further, if not we must refer for specialist assessment.

Low probability

For many of us, this is a straight forward decision: if asthma is unlikely, we should not treat as such and other options should be considered. If a diagnosis cannot be made, it is important to refer to specialist services for further assessment.

Diagnosing asthma

  • High probability: record a diagnosis of ‘suspected asthma’, treat appropriately and then review
  • Intermediate probability:  review the clinical history and spirometry or PEFR results alongside FeNO tests, consider referall for specialist assessment
  • Low probability: consider other diagnoses and refer to specialist services for further assessment if a diagnosis cannot be made.

PEFR=peak expiratory flow rate; FeNO=fractional exhaled nitric oxide

2. Documenting an asthma diagnosis

Once a diagnosis has been made, this must be clearly stated in the patient’s notes and coded appropriately. The documented diagnosis should be amended from ’suspected asthma’ to ‘asthma’, with free text providing an indication of why this diagnosis has been recorded and the evidence supporting the decision.

Following diagnosis, the patient should be provided with a personalised asthma action plan and advice concerning emergency treatment with a short-acting beta2 -agonist (SABA). There must also be an opportunity to address the patient’s questions about asthma and the ongoing management of their condition, including inhaler technique and other reviews.

3. No more steps

The guidance suggests that the traditional ‘steps’ should be removed, and clinicians may instead consider increasing and decreasing therapy in line with asthma control/symptoms.2

If a patient has responded to treatment and has been stable for a reasonable period, we can assess whether reducing therapy might be appropriate. Conversely, if a patient has worsening symptoms, we should consider increasing therapy.2

4. Specialist referral

If treatment is high and/or ineffective or the diagnosis is not clear, we must consider referring the patient to those with more specialist expertise.

Prompts for referral to a respiratory specialist:2

  • three or more courses of oral corticosteroids have been prescribed during the last year
  • the patient has been admitted to hospital with an exacerbation during the past 12 months
  • asthma is difficult to treat, despite high-dose ICS therapy
  • the patient been seen in accident and emergency a number of times.

Learning points for asthma diagnosis and management

  • Diagnosis and treatment may be less certain for some patients
  • It is important to establish whether there is a high, intermediate, or low probability of an asthma diagnosis
  • In general, an accurate asthma diagnosis will result in the patient demonstrating evidence of reversibility
  • Asthma therapy is effective for most patients with a confirmed diagnosis
  • Patients should be referred to specialist respiratory services when there is doubt concerning diagnosis
  • Failure to respond to treatment is a key prompt for specialist referral.


  1. British Thoracic Society, Research Unit of the Royal College of Physicians of London, King’s Fund Centre, National Asthma Campaign. Guidelines for management of asthma in adults: I—chronic persistent asthma. BMJ 1990; 301: 651–653.
  2. British Thoracic Society, Scottish Intercollegiate Guidelines Network. British guideline on the management of asthma. SIGN 153. BTS/SIGN, 2016. Available at:
  3. Gholap N, Davies M, Mostafa S, Khunti K. Diagnosing type 2 diabetes and identifying high-risk individuals using the new glycated haemoglobin (HbA1c) criteria. Br J Gen Pract 2013; 63 (607): e165–e167.
  4. Ritchie L, Campbell N. New NICE guidelines for hypertension. BMJ 2011; 343: d5644

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