Definition & Key Features

What is Asthma? Asthma is a chronic inflammatory disorder of the airways characterised by reversible bronchoconstriction and airway hyperresponsiveness.

Core Pathophysiology: Involves airway inflammation, intermittent airflow obstruction due to smooth muscle contraction, increased mucus secretion, and airway wall oedema. Over time, airway remodelling can occur.

Hallmark Features: Variable and recurring respiratory symptoms such as wheeze, breathlessness, chest tightness, and cough, particularly if these symptoms:

• Are worse at night and in the early morning.
• Occur in response to specific triggers (e.g., exercise, allergen exposure, cold air).
• Show personal or family history of other atopic conditions (eczema, allergic rhinitis).

Typical Signs/Symptoms:

• Wheeze: Expiratory polyphonic wheeze on auscultation (though absence doesn’t exclude asthma).
• Cough: Often dry, recurrent, may be nocturnal.
• Breathlessness: Episodic, variable.
• Chest tightness.
• Symptoms often vary in intensity and frequency.

Important Complications or Side Effects if Untreated/Poorly Controlled:

• Asthma exacerbations (attacks).
• Hospital admissions or emergency department visits.
• Impaired lung function development or decline.
• Reduced quality of life, including impact on daily activities, school, or work.
• Time off work or school.
• Risk of life-threatening attacks.

Epidemiology & Risk Factors

Who is most affected? Asthma can affect individuals of any age, often starting in childhood.

Risk Factors:

• Non-Modifiable:
  • Personal or family history of asthma.
  • Personal or family history of atopic diseases (e.g., eczema, allergic rhinitis).
• Modifiable/Environmental (can also be triggers or contribute to poor control):
  • Occupational exposures (check for work-related symptom patterns).
  • Smoking (active or passive), including vaping.
  • Allergen exposure (e.g., house dust mites, pollens, animal dander).
  • Air pollution (indoor and outdoor).
  • Indoor mould exposure.
  • Respiratory infections.
  • Certain medications (e.g., NSAIDs, beta-blockers).
  • Psychosocial factors.
  • Seasonal factors.

Clinical Presentation & Diagnosis

Typical Symptoms: Recurrent episodes of wheeze, cough, breathlessness, chest tightness. Symptoms may show diurnal variation (worse at night/early morning) or be triggered.

Red Flags (Indications for urgent referral or action/consideration):

• Acutely unwell or highly symptomatic at presentation: Treat immediately; perform objective tests when symptoms controlled if not possible initially.
• Children <5 years:
  • Refer to a specialist respiratory paediatrician if:
    • Hospital admission for wheeze.
    • Two or more emergency department attendances with wheeze in a 12-month period.
    • Not responding to an 8-12 week trial of inhaled corticosteroids (ICS) despite checking adherence, inhaler technique, environmental factors, and alternative diagnoses.
    • Uncontrolled on paediatric moderate-dose ICS and a trial of a leukotriene receptor antagonist (LTRA).
• Suspected occupational asthma: Refer to an occupational asthma specialist. Ask about symptom patterns related to work days vs. days off/holidays.
• Diagnostic uncertainty after initial objective tests.
• Poorly controlled asthma despite appropriate initial management steps in primary care (see Further Management section for specific referral points).

Diagnostic Criteria:

• No diagnosis of asthma without both a suggestive clinical history AND supporting objective test results. Code as ‘suspected asthma’ until confirmed. Record the basis of diagnosis.
• Physical examination may reveal expiratory polyphonic wheeze, but normal findings do not exclude asthma.

Objective Tests for Diagnosis (BTS/NICE/SIGN 2024):

Adults (17 years and over) & Young People (if using adult thresholds, typically >16 for these tests):

1. First Line: Measure blood eosinophil count OR Fractional Exhaled Nitric Oxide (FeNO).
   • Diagnose asthma if: Eosinophil count is above the laboratory reference range OR FeNO level is ≥50 ppb.
2. Second Line (if eosinophils/FeNO not indicative): Measure bronchodilator reversibility (BDR) with spirometry.
   • Diagnose asthma if: FEV1​ increase is ≥12% AND ≥200 ml from pre-bronchodilator measurement (OR if FEV1​ increase is ≥10% of predicted normal FEV1​).
3. Third Line (if spirometry unavailable/delayed): Measure peak expiratory flow (PEF) variability twice daily for 2 weeks.
   • Diagnose asthma if: PEF variability (amplitude % mean) is ≥20%.
4. Further Assessment: If asthma not confirmed by these tests but still suspected on clinical grounds, refer for consideration of a bronchial challenge test. Diagnose asthma if bronchial hyper-responsiveness is present.

Children and Young People (Aged 5 to 16 years):

1. First Line: Measure FeNO level.
   • Diagnose asthma if: FeNO level is ≥35 ppb.
2. Second Line (if FeNO not raised or testing unavailable): Measure BDR with spirometry.
   • Diagnose asthma if: FEV1​ increase is ≥12% from baseline (OR if FEV1​ increase is ≥10% of predicted normal FEV1​).
3. Third Line (if spirometry unavailable/delayed): Measure PEF variability twice daily for 2 weeks.
   • Diagnose asthma if: PEF variability (amplitude % mean) is ≥20%.
4. Further Assessment: If asthma not confirmed but still suspected:
   • Perform skin prick testing to house dust mite (HDM) OR measure total IgE level and blood eosinophil count.
   • Diagnose asthma if: Evidence of sensitisation to HDM OR raised total IgE AND blood eosinophil count >0.5×109 per litre.
   • Exclude asthma if: No evidence of sensitisation to HDM on skin prick testing OR total serum IgE is not raised.
5. Referral: If still doubt about diagnosis, refer to a paediatric specialist for a second opinion, including consideration of a bronchial challenge test.

Children Under 5 Years:

• Diagnosis is challenging as objective tests are difficult.
• For children with suspected asthma, treat with inhaled corticosteroids (ICS) (see Initial Management) and review regularly.
• If symptoms persist when they reach 5 years, attempt objective tests.
• If unable to perform objective tests at age 5, try again every 6-12 months. Refer for specialist assessment if asthma is not responding to treatment.

Important Considerations for Investigations:

• Treat acutely unwell/highly symptomatic patients immediately; perform objective tests later if necessary.
• Results of spirometry and FeNO may be affected (more likely normal) in people recently treated with ICS.

Differential Diagnoses:

• Consider alternative diagnoses based on symptoms (refer to tables in the full BTS/SIGN guideline, e.g., for wheezy children and adults).

Principles of Pharmacological Treatment (All Ages):

Initial Management

• Before starting/adjusting medicines, address: alternative diagnoses, comorbidities, suboptimal adherence, poor inhaler technique, smoking (active/passive, vaping), occupational/environmental exposures, psychosocial factors, seasonal factors.
• Check FeNO if asthma uncontrolled (raised may indicate poor adherence or need for increased ICS).
• CRITICAL: Do NOT prescribe short-acting beta2 agonists (SABAs) without a concomitant prescription of an ICS.
• Review treatment response in 8-12 weeks.
• Inhaler Choice: Base on assessment of correct technique, patient preference, lowest environmental impact among suitable devices, and presence of an integral dose counter. A spacer should usually be prescribed with a metered-dose inhaler (MDI), particularly in children. Prescribe same type of device for preventer and reliever if possible.

Initial Pharmacological Treatment (BTS/NICE/SIGN 2024):

Adults and Young People (12 years and over) – Newly Diagnosed Asthma:

• First-line: Offer a low-dose ICS/formoterol combination inhaler to be taken as needed for symptom relief (as-needed Anti-Inflammatory Reliever [AIR] therapy).
  • Note (Nov 2024): Only certain budesonide/formoterol Dry Powder Inhalers (DPIs) are licensed for as-needed AIR therapy in mild asthma. Other ICS/formoterol inhalers for this use would be off-label.
• If presenting highly symptomatic or with a severe exacerbation: Start treatment with low-dose Maintenance And Reliever Therapy (MART) using an ICS/formoterol inhaler (i.e., for daily maintenance AND as-needed relief) PLUS treat acute symptoms (e.g., oral corticosteroids). Consider stepping down to as-needed AIR therapy later if asthma is controlled.

Children Aged 5 to 11 Years – Newly Diagnosed Asthma:

• First-line: Offer a twice-daily paediatric low-dose ICS (maintenance) with a SABA as needed for symptom relief.

Children Under 5 Years – Suspected Asthma Requiring Maintenance:

• Consider an 8-12 week trial of twice-daily paediatric low-dose ICS (maintenance) with a SABA as needed if:
  • Symptoms at presentation indicate need for maintenance therapy (e.g., interval symptoms in a child with another atopic disorder).
  • Severe acute episodes of difficulty breathing/wheeze (e.g., requiring hospital admission or ≥2 courses of oral corticosteroids).
• Review after 8-12 weeks:
  • If symptoms resolve: Consider stopping ICS and SABA. Review symptoms after a further 3 months.
  • If symptoms do not resolve: Check inhaler technique, adherence, environmental factors, alternative diagnosis. If none explain failure, refer to specialist.

Major Side Effects, Contraindications, Cautions:

• ICS: Potential for local (oral thrush, dysphonia – mitigate with spacer and mouth rinsing) and systemic side effects (especially at high doses, long-term). Be aware ICS can affect diagnostic test results.
• Formoterol (in AIR/MART): Standard beta2 agonist side effects (tremor, palpitations) are possible but less common with inhaled route and when combined with ICS.
• SABA: Over-reliance indicates poor control. Do not use without ICS.
• Leukotriene Receptor Antagonists (LTRAs, e.g., Montelukast):
  • MHRA Safety Advice: Risk of neuropsychiatric reactions (e.g., agitation, sleep disturbances, depression, suicidal thinking). Advise patients/carers and monitor.
• Inhaler technique: Critical for efficacy. Check at every review.

Non-Pharmacological Measures:

• Smoking/vaping cessation advice and support.
• Encourage avoidance of known triggers where feasible.
• Address environmental factors (e.g., air pollution, indoor mould).
• Weight management if obese.
• Breathing exercises may be considered as an adjunct (not in provided text but general advice).

Patient Education:

• Nature of asthma (chronic, variable).
• Purpose and correct use of all prescribed inhalers (and spacers).
• Difference between preventer and reliever medication.
• Importance of adherence to preventer therapy.
• Provide a Personalised Asthma Action Plan (PAAP). This should include:
  • How to recognise worsening asthma.
  • How and when to adjust medication (e.g., increasing ICS dose for adults).
  • When to seek urgent medical attention.
  • Approaches for minimising exposure to air pollution and other personal triggers.
• Advice on inhaler disposal (return to pharmacy).

Initial Monitoring Parameters:

• Review response to new treatment in 8-12 weeks.
• Monitor asthma control: daytime symptoms, night-time waking, reliever use (≥3 days/week suggests poor control), activity limitation, exacerbations, oral corticosteroid use, hospital/ED visits.
• Consider validated symptom questionnaires (e.g., Asthma Control Test [ACT], Asthma Control Questionnaire [ACQ]).
• For adults, consider FeNO monitoring at regular reviews and before/after changing therapy.
• Regular PEF monitoring is NOT routinely recommended unless for specific person-specific reasons (e.g., part of PAAP).

Further Management & Escalation

Next Steps if First-Line Fails or is Contraindicated (BTS/NICE/SIGN 2024):

Adults and Young People (12 years and over):

1. Uncontrolled on as-needed low-dose ICS/formoterol (AIR therapy):
   • Offer low-dose MART (Maintenance And Reliever Therapy with ICS/formoterol).
2. Uncontrolled on low-dose MART:
   • Offer moderate-dose MART.
3. Uncontrolled on moderate-dose MART (despite good adherence):
   • Check FeNO and blood eosinophil count. If either raised, refer to a specialist in asthma care.
   • If FeNO and eosinophils NOT raised: Consider a trial of either an LTRA or a long-acting muscarinic receptor antagonist (LAMA), in addition to moderate-dose MART.
     • Trial for 8-12 weeks.
     • If asthma controlled, continue.
     • If control improved but still inadequate, continue current add-on and start a trial of the other (LAMA or LTRA).
     • If control not improved, stop the ineffective add-on and start a trial of the alternative.
4. Referral: Refer to a specialist if asthma is not controlled despite moderate-dose MART and trials of an LTRA and a LAMA. (See Accelerated Access Collaborative consensus pathway for uncontrolled adult asthma).
5. Transferring from old regimens (e.g., SABA only, ICS + SABA, ICS/LABA + SABA):
   • SABA only: Change to low-dose ICS/formoterol as-needed (AIR therapy).
   • Uncontrolled on regular low/moderate dose ICS (+/- LTRA) + SABA as needed, OR regular low/moderate dose ICS/LABA (+/- LTRA) + SABA as needed: Consider changing to low-dose or moderate-dose MART respectively.
   • When changing from ICS/LABA + supplementary therapy to MART, decide whether to continue supplementary therapy based on prior benefit.
   • Refer if uncontrolled on high-dose ICS.

Children Aged 5 to 11 Years:

1. Uncontrolled on paediatric low-dose ICS + SABA as needed:
   • MART Pathway (if child can manage MART regimen; off-label use for <12 years as of Nov 2024):
     • Consider paediatric low-dose MART.
     • If uncontrolled on low-dose MART: Consider paediatric moderate-dose MART.
   • Conventional Pathway (if unable to manage MART):
     • Consider adding an LTRA to twice-daily paediatric low-dose ICS + SABA (trial for 8-12 weeks; stop if ineffective).
     • If uncontrolled on paediatric low-dose ICS (+/- LTRA) + SABA: Offer twice-daily paediatric low-dose ICS/LABA combination inhaler + SABA as needed.
     • If uncontrolled on paediatric low-dose ICS/LABA (+/- LTRA) + SABA: Offer twice-daily paediatric moderate-dose ICS/LABA + SABA as needed.
2. Referral: Refer to a specialist in asthma care if asthma is not controlled on paediatric moderate-dose MART OR paediatric moderate-dose ICS/LABA (with or without LTRA, depending on previous response).

Children Under 5 Years:

1. Trial of low-dose ICS fails (symptoms don’t resolve in 8-12 weeks):
   • Check inhaler technique and adherence.
   • Check for environmental triggers (mould, cold housing, smokers, indoor pollution).
   • Review if an alternative diagnosis is likely.
   • If none explain failure, refer to a specialist in asthma care.
2. Symptoms resolved on ICS trial, but recur by 3-month review OR child has acute episode needing systemic corticosteroids or hospitalisation:
   • Restart regular ICS (paediatric low-dose, titrate to paediatric moderate-dose if needed) + SABA as needed.
   • Consider a further trial without treatment after reviewing the child within 12 months.
3. Suspected asthma uncontrolled on paediatric moderate-dose ICS + SABA:
   • Consider adding an LTRA (trial for 8-12 weeks; stop if ineffective).
4. Suspected asthma uncontrolled on paediatric moderate-dose ICS + SABA AND LTRA trial unsuccessful/not tolerated:
   • Stop LTRA.
   • Refer the child to a specialist in asthma care.

Referral Criteria (Summary):

• Diagnostic uncertainty after initial tests.
• Suspected occupational asthma.
• Adults (≥12y): Uncontrolled on moderate-dose MART + trials of LTRA and LAMA; or uncontrolled on high-dose ICS. Raised FeNO/eosinophils when on moderate-dose MART with poor control.
• Children (5-11y): Uncontrolled on paediatric moderate-dose MART or moderate-dose ICS/LABA (+/- LTRA).
• Children (<5y): Admission for wheeze or ≥2 ED visits in 12 months; failure to respond to initial ICS trial after checks; uncontrolled on moderate ICS + LTRA.

Specialist Interventions:

• Further diagnostic tests (e.g., bronchial challenge).
• Management of difficult-to-treat asthma.
• Consideration of biologic therapies for severe asthma (e.g., anti-IgE, anti-IL5/5R, anti-IL4R, anti-TSLP) based on phenotype (e.g. eosinophilic, allergic) and specific criteria. (These are managed by specialists).

Surgical Options: Bronchial thermoplasty is a highly specialist procedure for selected adults with severe asthma, not typically a GP consideration for escalation.

Follow-up & Safety Netting

Frequency of Follow-up Visits:

• At least annually for all people with asthma.
• After any exacerbation.
• 8-12 weeks after starting or adjusting medicines to review response.
• Children <5 on trial of ICS: Review after 8-12 weeks. If treatment stopped, review symptoms again after 3 months.
• Decreasing maintenance therapy: Allow at least 8-12 weeks before considering further reduction.

Monitoring Requirements (at every review):

• Asthma control:
  • Daytime symptoms, night-time waking due to asthma.
  • Need for reliever inhaler (prescription record check; ≥3 times a week is marker of poor control). Over-use of SABA (e.g. >2 inhalers per year) is a risk factor for poor outcomes.
  • Asthma attacks/exacerbations.
  • Courses of oral corticosteroids.
  • Hospital admissions or emergency department visits due to asthma.
  • Limitations on activity including exercise.
  • Time off work or school due to asthma.
• Validated symptom questionnaire (e.g., ACT, ACQ, C-ACT for children) – consider using.
• Inhaler technique: Observe use at every review.
• Adherence: Check using prescription records and discussion.
• Personalised Asthma Action Plan (PAAP): Review and update. Ensure understanding.
• FeNO monitoring (adults): Consider at regular review and before/after changing therapy.
• PEF monitoring: Not for routine assessment unless person-specific reasons (e.g., part of PAAP for some individuals).

Patient Advice on Self-Management:

• Reinforce use of PAAP.
• For adults (≥17y) using ICS in a single inhaler: PAAP may include advice to increase ICS dose (e.g., quadruple regular dose, not exceeding max licensed daily dose) for 7 days when asthma control deteriorates. Clearly outline how/when to do this and what to do if symptoms don’t improve.
• Recognising triggers and minimising exposure (including air pollution, both indoor and outdoor).
• When to seek review if control deteriorates.
• Importance of routine reviews.

Health Promotion:

• Smoking/Vaping Cessation: Strongly advise and offer support to all smokers/vapers, especially adolescents and pregnant women.
• Vaccinations: Offer influenza vaccine annually. Offer pneumococcal vaccine as per national guidance. (Standard practice, not explicitly detailed for routine asthma in snippet but crucial).
• Physical activity: Generally encouraged; ensure asthma is well-controlled to allow participation.

Warning Signs Prompting Urgent Reassessment (Safety Netting):

• Increasing symptom frequency or severity.
• Increasing use of reliever inhaler.
• Nocturnal waking due to asthma.
• Progressive limitation of daily activities.
• PEF readings falling (if part of PAAP).
• Failure to respond to usual reliever medication during an acute episode.
• Symptoms persist despite following PAAP advice for an exacerbation.
• Any features of an acute severe or life-threatening asthma attack (e.g., inability to complete sentences, exhaustion, cyanosis, silent chest, PEF <33-50% best/predicted) require immediate emergency assessment.

Risk Stratification:

• Actively identify people at risk of poor outcomes (non-adherence, SABA over-use [>2 inhalers/year], ≥2 courses oral corticosteroids/year, ≥2 ED visits or any hospital admission for asthma) and tailor care.

Key Points to Remember

• Diagnosis: Requires BOTH suggestive history AND objective tests (FeNO, Spirometry with BDR, PEF variability; thresholds vary by age).
• No SABA Monotherapy: Always co-prescribe an ICS if a SABA is needed.
• Initial Tx (≥12y): As-needed low-dose ICS/formoterol (AIR therapy) for mild/moderate. Low-dose MART if more symptomatic.
• Initial Tx (5-11y): Paediatric low-dose ICS daily + SABA as needed.
• Initial Tx (<5y): Trial of paediatric low-dose ICS + SABA as needed if symptomatic/severe episodes.
• MART Strategy: Key for those ≥12y whose asthma is not controlled on AIR therapy, involving using ICS/formoterol for both maintenance and relief.
• Inhaler Technique & Adherence: Check at EVERY review. Critical for effective treatment.
• Personalised Asthma Action Plan (PAAP): Essential for all patients for self-management. Review and update regularly.
• Referral Triggers: Know when to refer for diagnostic uncertainty or uncontrolled asthma despite optimized primary care management (specific thresholds apply).
• Montelukast: Be aware of MHRA warning regarding neuropsychiatric side effects.

Take-Home Points

1. Confirm with Objective Tests: Don’t diagnose asthma on history alone. Use FeNO/spirometry according to age-specific pathways.
2. ICS is Cornerstone: Avoid SABA-only treatment. For those ≥12 years, initial treatment is typically as-needed low-dose ICS/formoterol (AIR).
3. Empower with PAAP: Every patient needs a Personalised Asthma Action Plan and regular checks of inhaler technique and adherence.

This MedDigest summary is intended for educational purposes only and should not be used for clinical purposes. It is an independent resource, prepared by MedDigest, to offer an accessible overview of information drawn from the NICE guidelines. While MedDigest strives for accuracy in its educational summaries, this content has not been reviewed or produced by NICE. For comprehensive and definitive recommendations, please always refer to the complete NICE guidelines.

References

NICE (27 November 2024) Asthma pathway (BTS, NICE, SIGN). https://www.nice.org.uk/guidance/ng244

NICE (27 November 2024) Asthma: diagnosis, monitoring and chronic asthma management (BTS, NICE, SIGN). https://www.nice.org.uk/guidance/ng245