Key Facts

Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable condition characterised by persistent airflow limitation that is usually progressive and associated with an enhanced chronic inflammatory response to noxious particles or gases, most commonly cigarette smoke.

Epidemiology

• ~1.2 million diagnosed with COPD in the UK; estimated 2 million undiagnosed
• 3rd leading cause of death globally; 5th in the UK (~30,000 deaths/year)
• Prevalence increases with age: ~10% in over-40s
• More common in men historically, but female rates increasing
• Strong association with socioeconomic deprivation

Aetiology

• Cigarette smoking: ~85-90% of UK COPD cases (~15-20% of smokers develop COPD)
• Occupational exposure: coal dust, silica, cadmium, grain dust (~15%)
• Alpha-1 antitrypsin deficiency: ~1-2% of cases; suspect if onset <45 years or non-smoker
• Biomass fuel exposure: significant cause in developing countries
• Air pollution: contributes to disease progression
• Childhood respiratory infections and low birth weight increase susceptibility

Pathophysiology

• Chronic bronchitis: mucus gland hypertrophy, goblet cell hyperplasia, chronic airway inflammation → productive cough, airway narrowing
• Emphysema: destruction of alveolar walls (loss of elastic recoil) by neutrophil elastase and oxidative stress → air trapping, hyperinflation, gas exchange impairment
• Protease-antiprotease imbalance: excess neutrophil elastase overwhelms alpha-1 antitrypsin
• Small airway fibrosis and mucus plugging contribute to fixed obstruction
• Progressive decline in FEV₁ (~50-80 mL/year vs ~30 mL/year in non-smokers)

Typical Presentation

• Chronic progressive breathlessness, initially on exertion
• Chronic cough, often productive with sputum (especially in chronic bronchitis phenotype)
• Wheeze
• Smoking history (usually ≥20 pack-years)
• Age typically >35 years at diagnosis
• Recurrent chest infections

Clinical Signs

• Barrel chest (hyperinflation)
• Pursed-lip breathing
• Use of accessory muscles
• Reduced chest expansion
• Hyperresonant percussion
• Reduced breath sounds, expiratory wheeze
• Peripheral oedema and raised JVP (cor pulmonale in advanced disease)

Phenotypes

• Pink puffer (predominantly emphysema): thin, tachypnoeic, pursed-lip breathing, minimal cyanosis
• Blue bloater (predominantly chronic bronchitis): overweight, cyanotic, oedematous, productive cough

Red Flags

• Rapid FEV₁ decline (>80 mL/year)
• Onset <45 years (consider alpha-1 antitrypsin deficiency)
• Frequent exacerbations (≥2/year)
• Signs of cor pulmonale
• Unexplained weight loss (consider lung cancer)
• Haemoptysis (exclude malignancy)

Bedside

• Post-bronchodilator spirometry: FEV₁/FVC <0.7 confirms airflow obstruction (NICE NG115)
• Pulse oximetry: baseline SpO₂
• BMI: nutritional status assessment
• MRC dyspnoea scale: grade 1-5 breathlessness

Bloods

• FBC: polycythaemia (chronic hypoxia), anaemia
• Alpha-1 antitrypsin level: all patients at diagnosis (NICE)
• U&Es: baseline
• CRP: if infective exacerbation suspected
• BNP/NT-proBNP: if cor pulmonale/heart failure suspected
• Eosinophil count: guides ICS use (≥300 cells/µL favours ICS)

Imaging

• Chest X-ray: hyperinflation, flattened diaphragms, bullae, exclude other pathology
• CT chest: emphysema distribution, bullae, bronchiectasis, lung cancer screening

Special Tests

• TLCO (transfer factor): reduced in emphysema; helps distinguish from asthma (normal TLCO)
• ABG: if SpO₂ ≤92% or GOLD 3-4 — assess for LTOT
• 6-minute walk test: exercise capacity and desaturation
• Full pulmonary function tests: lung volumes (increased RV/TLC in emphysema)
• Sputum culture: if persistent purulent sputum or frequent exacerbations
• ECG/Echo: right heart assessment if cor pulmonale suspected

Non-pharmacological

• Smoking cessation: most important intervention (offer NRT, varenicline 0.5mg OD for 3 days then 1mg BD for 12 weeks, or bupropion)
• Pulmonary rehabilitation: for MRC dyspnoea grade ≥3; 6-12 week supervised exercise and education programme
• Annual influenza and pneumococcal vaccination
• Nutritional support: if BMI <20 kg/m²
• Self-management plan with rescue pack (antibiotics + prednisolone)

Pharmacological

NICE NG115 stepwise approach:

Step 1: SABA (salbutamol 100-200mcg PRN) or SAMA (ipratropium 20-40mcg PRN)

Step 2 — based on phenotype:

• No asthmatic features/eosinophilia: LABA (salmeterol 50mcg BD) or LAMA (tiotropium 18mcg OD via HandiHaler or 5mcg via Respimat)
• Asthmatic features or eosinophils ≥300: LABA + ICS (e.g. budesonide/formoterol)

Step 3:

• Non-eosinophilic: LABA + LAMA (e.g. umeclidinium/vilanterol or tiotropium + olodaterol)
• Eosinophilic: LABA + LAMA + ICS triple therapy (e.g. fluticasone furoate/umeclidinium/vilanterol — Trelegy; IMPACT trial)

Additional therapies:

• Roflumilast 500mcg OD: PDE4 inhibitor for frequent exacerbations with FEV₁ <50% (REACT trial)
• Azithromycin 250mg 3×/week: prophylactic for frequent exacerbations (non-smokers, exclude QT prolongation)
• Mucolytics: carbocisteine 750mg TDS — consider if chronic productive cough

Oxygen therapy:

• LTOT: PaO₂ ≤7.3 kPa on 2 stable ABGs 3 weeks apart; or ≤8.0 kPa with cor pulmonale/polycythaemia
• Must use ≥15 hours/day; smoking cessation mandatory
• Ambulatory oxygen: if desaturation on exercise and benefit demonstrated

Surgical/Interventional

• Lung volume reduction surgery (LVRS): selected upper-lobe predominant emphysema with low exercise capacity (NETT trial)
• Endobronchial valves: heterogeneous emphysema with intact fissures (NICE IPG600; LIBERATE trial)
• Bullectomy: large bullae compressing functional lung
• Lung transplantation: end-stage COPD, BODE index 7-10, age <65

Referral Criteria

• Diagnostic uncertainty
• Rapid FEV₁ decline
• Frequent exacerbations (≥2/year) despite optimal therapy
• Suspected alpha-1 antitrypsin deficiency
• Assessment for LTOT, pulmonary rehab, LVRS, transplant
• Cor pulmonale or persistent hypoxia

• COPD is the 3rd leading cause of death globally
• BODE index predicts mortality: BMI, Obstruction (FEV₁), Dyspnoea (MRC), Exercise capacity (6MWT)
• FEV₁ <30% predicted: ~5-year survival ~50%
• Smoking cessation improves survival at any stage
• Frequent exacerbations (≥2/year) associated with faster FEV₁ decline and increased mortality
• Cor pulmonale carries poor prognosis (~50% 5-year mortality)
• LTOT improves survival in hypoxic COPD (MRC and NOTT trials: ~5-year survival improved by 20-30%)
• Lung transplant: median survival ~5-6 years post-transplant

GOLD Severity Classification

MRC Dyspnoea Scale

BODE Index