Compare Step-up / control thresholds for Asthma across NICE and BTS/SIGN. Built for Adults. Setting: Primary & Secondary. Urgency: Routine.
Clear thresholds help clinicians answer "when do I act?" for asthma, aligning expectations between NICE and BTS/SIGN. Use this side-by-side view to decide when to refer, escalate, monitor, or initiate treatment.
Asthma affects approximately 5.4 million people in the UK, with adults representing a substantial proportion of this population. The clinical challenge lies in determining the optimal timing for treatment intensification—balancing the risk of uncontrolled asthma against potential overtreatment side effects. Approximately 3 people die from asthma each day in the UK, many from preventable causes where step-up thresholds were missed or delayed.
Getting step-up thresholds right is critical because delayed escalation can lead to emergency department visits, hospitalisations, and potentially fatal asthma attacks. Conversely, premature escalation exposes patients to unnecessary medication side effects and increases healthcare costs. NICE takes a pragmatic, evidence-based approach focusing on objective measures and structured care, while BTS/SIGN provides more detailed, consensus-driven guidance with stronger emphasis on symptom patterns and patient-reported outcomes.
| Guideline | Primary Focus | Typical Setting | Publication/Update |
|---|---|---|---|
| NICE | Evidence-based standardisation across NHS | Primary care with secondary care integration | NG80 (2017, updated 2021) |
| BTS/SIGN | Comprehensive clinical management guidance | Both primary and secondary care | 2024 (latest update) |
Primary care clinicians should use NICE as the default guidance for routine asthma management, while BTS/SIGN provides valuable additional detail for complex cases and specialist settings. Cross-reference between guidelines when patients show poor response to initial step-up or when managing comorbidities that complicate asthma treatment decisions.
| Threshold Parameter | NICE Position | BTS/SIGN Position | Clinical Notes |
|---|---|---|---|
| FEV1 % predicted | Consider step-up if <80% despite current treatment | Step-up if <75% or excessive variability | BTS/SIGN more sensitive to variability |
| Daily symptom frequency | Step-up if symptoms ≥3 times/week affecting sleep/activity | Step-up if symptoms most days or nightly symptoms | NICE uses more specific frequency thresholds |
| SABA use | Step-up if using SABA ≥3 times/week | Step-up if requiring SABA most days | Both emphasise SABA use as control indicator |
| ACQ-6 score | Step-up if score ≥1.5 despite treatment | Supports ACQ use but no fixed threshold | NICE provides specific numeric threshold |
NICE Approach: Recommends formal asthma review within 48 hours after step-up decision, then 4-8 week follow-up to assess response. Specific monitoring intervals include: peak flow diary assessment over 2-4 weeks; ACQ-6 reassessment at 3 months; structured medication review at each step change. Special populations: elderly patients may require slower step-up with closer monitoring for side effects.
BTS/SIGN Approach: Emphasises more frequent initial assessment with review within 1-2 weeks after step-up, particularly for patients with recent exacerbations. Monitoring focuses on: symptom diaries reviewed weekly for first month; lung function reassessment at 4-6 weeks; personalised action plan updates at each visit. Unique perspective includes stronger emphasis on exhaled nitric oxide (FeNO) monitoring in selected patients.
| Trigger Scenario | NICE Recommendation | BTS/SIGN Recommendation |
|---|---|---|
| Failed step-up after 3 months | Refer to specialist asthma service | Consider referral after 2 failed steps or poor response |
| FEV1 <60% despite treatment | Urgent respiratory referral | Immediate specialist assessment |
| ≥2 exacerbations requiring oral steroids in 12 months | Refer for specialist optimisation | Prompt respiratory consultant review |
| Suspected occupational asthma | Early specialist referral | Immediate occupational asthma service referral |
| Adverse effects from high-dose ICS | Refer for alternative treatment options | Specialist review for side effect management |
| Psychosocial factors affecting control | Consider multidisciplinary referral | Recommend psychology/specialist nurse input |
Presentation: 45-year-old female, Step 2 treatment (low-dose ICS), FEV1 78% predicted, symptoms 2-3 times/week, using SABA twice weekly, ACQ-6 score 1.4.
Analysis: NICE would not step up as FEV1 >75% and ACQ-6 <1.5. BTS/SIGN would likely step up due to persistent symptoms most days. Most appropriate action: shared decision-making discussing potential benefits versus risks of higher dose ICS, with close 4-week review.
Presentation: 72-year-old with COPD overlap, osteoporosis, FEV1 65%, daily symptoms but infrequent SABA use due to fear of side effects.
Analysis: NICE would step up to moderate-dose ICS with caution due to osteoporosis risk. BTS/SIGN would consider LABA before higher ICS doses and emphasise inhaler technique assessment. Action: step-up with bone protection review, prioritise inhaler technique, consider dual therapy rather than high-dose monotherapy.
While no single validated tool exists for asthma step-up decisions, both guidelines support using structured assessment tools. The Asthma Control Questionnaire (ACQ-6) is strongly recommended by NICE with a specific threshold of ≥1.5 indicating need for step-up. BTS/SIGN acknowledges ACQ but also supports the Asthma Control Test (ACT) and Royal College of Physicians 3 Questions.
Practical application involves calculating ACQ-6 at each review: scores incorporate symptoms, FEV1%, and SABA use. Interpretation thresholds: <0.75 = well controlled; 0.75-1.5 = partly controlled; >1.5 = uncontrolled. Additional factors for clinical judgment include exacerbation history, adherence assessment, inhaler technique, and environmental trigger exposure.
| Guideline body | Position | Population & urgency |
|---|---|---|
| NICE | Position on Step-up / control thresholds for Asthma | Adults | Urgency: Routine | Setting: Primary & Secondary |
| BTS/SIGN | Position on Step-up / control thresholds for Asthma | Adults | Urgency: Routine | Setting: Primary & Secondary |
This comparison is intended for clinical decision support and education. Always refer to the full published guidelines for definitive recommendations and the most up-to-date evidence. Clinical decisions should be individualized based on patient context and preferences.