For a patient in whom I need to decide between chronic obstructive pulmonary disease and asthma, what are the recommended medication regimens for each diagnosis?

Distinguishing COPD from Asthma: Medication Regimens

For COPD, start with bronchodilators (short-acting β2-agonist or anticholinergic) as first-line therapy, escalating to combination bronchodilators for moderate-severe disease, while for asthma, initiate anti-inflammatory therapy with inhaled corticosteroids as the foundation of treatment. 1

Key Diagnostic Distinctions Before Treatment

Perform spirometry with bronchodilator reversibility testing to differentiate these conditions before committing to a treatment regimen. 2, 3

• Asthma diagnosis: FEV1 improvement >200 mL AND >15% (or >12% in some criteria) after bronchodilator administration 2, 3
• COPD diagnosis: FEV1/FVC ratio <70% that remains persistently low despite bronchodilator administration 3
• Critical pitfall: A substantial bronchodilator response suggests asthma rather than COPD, though 10-20% of COPD patients show some objective improvement with corticosteroid trials 2

COPD Medication Regimen (Severity-Based Algorithm)

Mild COPD

• Short-acting β2-agonist (salbutamol) OR inhaled anticholinergic (ipratropium) as needed 2
• Anticholinergics are particularly appropriate as first-line since bronchoconstriction in COPD is largely cholinergically mediated 1

Moderate COPD

• Regular bronchodilator therapy with either β2-agonist or anticholinergic, or combination of both 2
• Consider a corticosteroid trial (30 mg prednisolone daily for 2 weeks with pre/post spirometry) in all moderate COPD patients 2
• Only continue inhaled corticosteroids if objective improvement occurs (FEV1 increase ≥200 mL and ≥15%) 2

Severe COPD

• Combination therapy with regular β2-agonist PLUS anticholinergic as the foundation 2, 4
• Add inhaled corticosteroids only for patients with severe airflow obstruction and frequent exacerbations who remain symptomatic despite maximized bronchodilation 1, 5
• Consider theophylline if additional bronchodilation needed (target serum level 5-15 μg/L) 2
• Important limitation: Long-acting β2-agonists should only be used if objective evidence of improvement is documented 2

Critical COPD Caveats

• Theophyllines have limited value in routine COPD management 2
• No role exists for other anti-inflammatory drugs beyond corticosteroids in COPD 2
• Inhaled corticosteroids do NOT reduce the progressive decline in lung function that characterizes COPD 5

Asthma Medication Regimen

First-Line Asthma Therapy

• Inhaled corticosteroids are the mainstay and first-line therapy for persistent asthma 1
• Leukotriene modifiers serve as alternative first-line anti-inflammatory agents 1
• Short-acting β2-agonists for rescue/as-needed symptom relief 1

Rationale for Different Approach

The inflammatory profile differs fundamentally between diseases:

• Asthma: Eosinophils, mast cells, and CD4+ TH2-lymphocytes predominate, making corticosteroids highly effective 1
• COPD: Neutrophils, macrophages, and CD8+ lymphocytes predominate, explaining poor corticosteroid response 1

Asthma-COPD Overlap Considerations

When spirometry shows both reversibility (consistent with asthma) AND persistent baseline airflow limitation (consistent with COPD): 3

• Treat primarily according to asthma guidelines with inhaled corticosteroids as foundation 3
• Add COPD-specific bronchodilator strategies (particularly anticholinergics) as needed 3
• These patients may have accelerated lung function decline and worse prognosis, requiring early identification 6

Acute Exacerbation Management Differences

COPD Exacerbations

• Nebulized β-agonist (salbutamol 2.5-5 mg) plus ipratropium bromide (500 μg) together 4
• Add oral corticosteroids if severe (cannot complete sentences, RR >25/min, HR >110/min) 4
• Oxygen caution: Drive nebulizers with air (not oxygen) if CO2 retention present 4

Asthma Exacerbations

• Nebulized β-agonist with oxygen 4
• Oral corticosteroids administered early in severe presentations 4
• Anticholinergics added if inadequate response to β-agonist alone 4

Essential Non-Pharmacological Interventions

• Smoking cessation is the ONLY intervention proven to slow COPD progression and must be emphasized at every visit 2, 7
• Influenza vaccination recommended for moderate-severe COPD 2
• Pulmonary rehabilitation improves exercise performance and reduces breathlessness in moderate-severe disease 2