FFinalistSouthampton · 2027
Respiratory
AKT · Respiratory/Airways diseaselow yield

Asthma-COPD overlap

Features of BOTH asthma (reversible, eosinophilic) and COPD (fixed, smoking-related) airflow obstruction

Overview

A clinical phenotype with features of both asthma and COPD — persistent airflow obstruction (like COPD) with significant variability/reversibility and eosinophilic/atopic features (like asthma). It typically affects older smokers with an atopic/asthma history and tends to have more frequent exacerbations. The practical point is that the ICS-responsive (eosinophilic) component means inhaled corticosteroids are central, unlike pure COPD.

Recognise

  • Persistent airflow obstruction in an older smoker WITH variability/reversibility and atopic or eosinophilic features (high blood eosinophils, raised FeNO, asthma history)
  • More frequent exacerbations and faster lung-function decline than either alone
  • Overlapping symptoms — breathlessness, wheeze, cough — with both fixed and variable components

Red flags

  • Frequent exacerbations → optimise inhaled therapy and address the eosinophilic component
  • Don't withhold an ICS (as you might in pure eosinophil-low COPD) — the asthma component is steroid-responsive

Differentials & how to tell them apart

Pure asthmayounger, fully reversible, no significant smoking-related fixed obstruction
Pure COPDsmoking-related fixed obstruction without atopy/eosinophilia or reversibility
Bronchiectasis / heart failureother causes of mixed breathlessness/wheeze

Investigations

Spirometry (obstruction with significant reversibility/variability), blood eosinophils and FeNO (eosinophilic/atopic component), CXR; history of asthma/atopy plus a smoking history; exclude other causes.

Management

ICS-containing inhaler (ICS/LABA ± LAMA) + smoking cessation + rehab

  1. 1Recognise overlap — fixed obstruction (COPD) PLUS reversibility/eosinophilic/atopic features (asthma) in an older smoker. Treat with ICS-containing inhaled therapy plus the COPD foundations (smoking cessation, rehab, vaccines).Gate: Unlike eosinophil-low COPD, do NOT withhold the ICS — the eosinophilic asthma component is steroid-responsive and ICS reduces exacerbations.
  2. 2Add a LAMA and optimise adherence/technique; manage frequent exacerbations and refer difficult cases for phenotyping/biologics.
ICS-containing inhaled therapy (ICS/LABA, often + LAMA) — the ICS treats the steroid-responsive asthma component — central here, unlike eosinophil-low COPD
Smoking cessation + pulmonary rehab + vaccines — the COPD foundations apply
Treat exacerbations + optimise adherence/technique — manage the frequent exacerbations
Specialist referral for difficult cases — phenotyping/biologics where appropriate

Key points

Older smoker + fixed obstruction + reversibility/eosinophilia/atopy = asthma-COPD overlap → ICS-containing inhaler (the asthma component is steroid-responsive, so ICS is central) + COPD foundations (stop smoking, rehab, vaccines). More exacerbations than either alone.

Monitor & prognosis

Exacerbations, eosinophils, lung function, inhaler technique.

More exacerbations and faster decline than either condition alone; ICS-based therapy helps.

Source: NICE NG115/NG245; GINA-GOLD overlap