Makindo Medical Notes

Asthma–COPD Overlap Syndrome (ACOS) is a condition where patients exhibit clinical and physiological features of both asthma and chronic obstructive pulmonary disease (COPD). It involves persistent airflow limitation with variable airway hyperreactivity. ⚠️ ACOS has worse outcomes than asthma or COPD alone, making diagnosis and treatment more challenging.

🔬 Pathophysiology

• 🌪️ Asthma Component: Chronic airway inflammation, eosinophilic infiltration, reversible obstruction (bronchospasm).
• 🔥 COPD Component: Irreversible obstruction, neutrophilic inflammation, alveolar destruction (emphysema) or chronic bronchitis.
• ⚡ Overlap Features: Persistent inflammation, airway hyperreactivity, incomplete reversibility of obstruction.

⚠️ Risk Factors

• 🚬 Smoking: Key driver of COPD; smokers with asthma at highest risk.
• 👵 Age: More common in older adults.
• 🏭 Occupational Exposure: Dusts, fumes, chemicals.
• 🧬 Genetic Factors: Family history of asthma or COPD.

🩺 Clinical Features

• 😮‍💨 Dyspnoea: Progressive breathlessness, worse on exertion.
• 🤧 Chronic Cough + Sputum: (more COPD-like).
• 🎵 Wheeze: Episodic, often asthma-like.
• 📈 Frequent Exacerbations: Higher than asthma/COPD alone.
• 🌙 Nocturnal Symptoms: Night cough or wheeze (asthma feature).
• 🫁 Airflow Limitation: Spirometry: persistent obstruction, partial reversibility post-bronchodilator.
• Exam: wheeze, hyperinflated chest, prolonged expiration.

🧪 Investigations

• 📉 Spirometry:
  • FEV1/FVC < 0.7 (fixed obstruction).
  • Partial reversibility: ≥12% & 200 mL FEV1 improvement, but not full normalization.
• 🧪 Biomarkers:
  • Peripheral eosinophilia → asthma component.
  • FeNO ↑ → eosinophilic inflammation.
• 🩻 Imaging:
  • Chest X-ray: hyperinflation, bronchial wall thickening.
  • CT: emphysema, airway changes.

💊 Pharmacological Management

• 🌿 ICS: First-line for asthma features (↓ inflammation, ↓ exacerbations).
• 💨 LABA: Bronchodilation (always in combination with ICS).
• 🛑 LAMA: Key for COPD component, reduces exacerbations.
• 🚑 SABA/SAMA: Rescue therapy (e.g., salbutamol, ipratropium).
• ⚡ Oral Steroids: Only for acute exacerbations.
• 🍃 LTRA: For allergic/asthmatic overlap cases.

🏃‍♂️ Non-Pharmacological Management

• 🚭 Smoking Cessation: Crucial step to prevent progression.
• 🏋️‍♀️ Pulmonary Rehabilitation: Exercise + education → improves QoL.
• 💉 Vaccinations: Annual flu + pneumococcal vaccine.
• 📘 Self-Management: Patient education on inhaler use, exacerbation recognition.

🚨 Exacerbation Management

• 💨 SABA/SAMA: Short-acting bronchodilators for relief.
• 💊 Systemic Steroids: Oral prednisolone or IV hydrocortisone.
• 🧫 Antibiotics: If bacterial infection suspected (purulent sputum, fever).
• 🫁 Oxygen: If SpO₂ < 90% (beware CO₂ retention in COPD).

📉 Prognosis

ACOS has a worse prognosis than asthma or COPD alone. ➡️ More frequent exacerbations, hospital admissions, and faster lung function decline. ✨ With early recognition, combination therapy (ICS + LABA/LAMA), and lifestyle changes, patients can achieve improved symptom control and quality of life.