What is the initial treatment for ankylosing spondylitis?

Initial Treatment for Ankylosing Spondylitis

Non-steroidal anti-inflammatory drugs (NSAIDs) at full therapeutic doses combined with supervised physical therapy should be the initial treatment for ankylosing spondylitis. 1

First-Line Therapy

• NSAIDs are strongly recommended as first-line therapy for active ankylosing spondylitis
• No particular NSAID is preferred over others; selection should be based on:
  • Patient comorbidities
  • Risk of cardiovascular, gastrointestinal, and renal adverse effects
  • Prior response to specific NSAIDs

NSAID Administration

• Use full therapeutic doses during disease flares
• Continuous treatment is conditionally recommended over on-demand treatment for persistent disease activity 1
• Assess response to NSAIDs within 2-4 weeks 1
• Approximately 75% of patients show a good response to NSAIDs within 48 hours 1

Physical Therapy

• Supervised physical therapy is a fundamental component of initial treatment 1
• Focus on:
  • Maintaining spinal mobility
  • Improving posture
  • Strengthening core and neck muscles

Monitoring and Treatment Progression

Response Assessment

• Evaluate clinical response within 2-4 weeks of starting NSAIDs 1
• Monitor inflammatory markers (CRP, ESR) at regular intervals 1
• Consider bone densitometry for osteoporosis detection, especially in patients with syndesmophytes or spinal fusion 1

Treatment Escalation

If inadequate response to NSAIDs after 2-4 weeks at full therapeutic doses:

1. For axial disease: Consider TNF inhibitors (adalimumab, etanercept, infliximab, golimumab) 1, 2

   • Etanercept is FDA-approved for reducing signs and symptoms in patients with active ankylosing spondylitis 2

2. For peripheral arthritis: Consider sulfasalazine as second-line treatment 1

   • Conventional DMARDs like methotrexate are not effective for axial disease but may be considered for peripheral arthritis 1

Important Considerations

Contraindications and Precautions

• Strong recommendation against using systemic glucocorticoids in active axial spondyloarthritis 1
• Consider cardiovascular, gastrointestinal, and renal risks when prescribing NSAIDs 1
• High-quality evidence from the Cochrane review indicates that withdrawals due to adverse events and serious adverse events did not differ significantly between placebo and NSAID groups in short-term studies 3

Pitfalls to Avoid

1. Inadequate NSAID dosing: Use full therapeutic doses before determining treatment failure 1, 4
2. Premature switching between NSAIDs: Try one NSAID at appropriate dosage before assuming inefficacy 4
3. Overlooking physical therapy: Physical therapy is essential, not optional 1
4. Delayed escalation to biologics: Consider TNF inhibitors promptly if inadequate response to NSAIDs 1, 2
5. Relying on conventional DMARDs for axial disease: These are ineffective for axial manifestations 1

Long-term Considerations

• Regular radiographic follow-up generally not necessary more frequently than every 2 years, unless significant changes in clinical status 1
• Continuous NSAID use may potentially reduce radiographic spinal progression, though this requires further confirmation 3
• Early diagnosis and treatment are crucial for preventing structural deformities 1

Treatment Algorithm

1. Start with full-dose NSAIDs + supervised physical therapy
2. Assess response after 2-4 weeks
3. If good response: Continue treatment, consider on-demand vs. continuous NSAID based on disease activity
4. If inadequate response:
   • For axial disease: Consider TNF inhibitors
   • For peripheral arthritis: Consider sulfasalazine

Despite the effectiveness of NSAIDs, approximately 20% of patients report insufficient pain control, and over 40% need to change their NSAID due to lack of efficacy 5. Therefore, close monitoring and timely treatment adjustment are essential for optimal management.