What is the role of colchicine in the treatment of pericarditis?

Role of Colchicine in Pericarditis

Colchicine is strongly recommended as a first-line treatment for acute pericarditis and for preventing recurrences, reducing recurrence rates by approximately 50% when added to conventional anti-inflammatory therapy. 1, 2

Mechanism and Efficacy

Colchicine works in pericarditis through several anti-inflammatory mechanisms:

• Inhibits microtubule assembly and leukocyte function
• Reduces inflammatory cytokine production
• Disrupts inflammatory cell migration to affected tissues

The evidence supporting colchicine use in pericarditis is robust:

• Reduces recurrence rates from 15-30% to approximately 8-15% after a first episode 1, 2
• Decreases symptom persistence at 72 hours (11.7% vs 36.7%) 3
• Number needed to treat (NNT) is only 5 patients to prevent one recurrence 4
• Particularly effective for idiopathic and viral pericarditis cases

Dosing and Administration

Colchicine should be administered as follows:

• Weight-adjusted dosing is critical:
  • For patients <70 kg: 0.5 mg once daily
  • For patients ≥70 kg: 0.5 mg twice daily 1, 2
• Treatment duration:
  • At least 3 months for first episode of pericarditis
  • At least 6 months for recurrent pericarditis 1
• No loading dose is recommended in current guidelines 1
• Always combined with NSAIDs or aspirin (not as monotherapy)

Treatment Algorithm

1. First episode of acute pericarditis:

   • First-line: NSAIDs/aspirin + colchicine + exercise restriction
   • Continue until symptoms resolve and CRP normalizes
   • Taper NSAIDs/aspirin first, then colchicine

2. Recurrent pericarditis:

   • First-line: NSAIDs/aspirin + colchicine + exercise restriction
   • Second-line (if contraindications to first-line): Low-dose corticosteroids
   • Third-line (for refractory cases): IV immunoglobulin, anakinra, or azathioprine
   • Fourth-line: Pericardiectomy 1

Monitoring and Safety

• Most common adverse effects are gastrointestinal (diarrhea in ~8% of patients) 3
• No serious adverse effects reported in major trials 3, 5
• Monitor CRP to guide treatment duration and assess response 1, 2
• Contraindicated in severe renal or hepatic impairment
• Dose adjustment needed in elderly patients and those with mild-moderate renal impairment

Clinical Pearls and Pitfalls

• Avoid corticosteroids as first-line therapy - they increase risk of recurrence and chronicity 1, 3
• Multivariate analysis shows corticosteroid use is an independent risk factor for recurrences (OR 4.30) 3
• Colchicine should be tapered gradually in recurrent cases to prevent symptom rebound
• Exercise restriction is recommended until symptoms resolve and CRP normalizes (minimum 3 months for athletes) 1
• Colchicine is effective for both acute and recurrent pericarditis, but shows greatest benefit in preventing recurrences

Prognosis

With appropriate colchicine therapy:

• Risk of constrictive pericarditis is <1% in idiopathic/viral cases 1, 2
• Cardiac tamponade is rare in patients with acute idiopathic pericarditis 1
• Quality of life significantly improves with reduced recurrence rates 1

The European Society of Cardiology gives a Class I, Level A recommendation for colchicine use in both acute and recurrent pericarditis, reflecting the highest level of evidence for its efficacy 1, 2.