What is the initial treatment for ankylosing spondylitis?

Initial Treatment for Ankylosing Spondylitis

The initial treatment for ankylosing spondylitis (AS) should be non-steroidal anti-inflammatory drugs (NSAIDs) at full therapeutic doses, used continuously in patients with persistent active disease. 1

First-Line Therapy: NSAIDs

Efficacy and Administration

• NSAIDs provide rapid relief of inflammatory symptoms including pain and stiffness
• High-quality evidence shows NSAIDs are effective for:
  • Pain relief (16.5 points lower on 100mm VAS compared to placebo) 2
  • Disease activity improvement (17.5 points lower BASDAI score) 2
  • Function improvement (9.1 points lower BASFI score) 2
• Dosing recommendations:
  • Use full therapeutic doses before declaring treatment failure 1
  • Consider continuous rather than on-demand use for persistent active disease 1
  • Higher doses may be prescribed before bedtime for patients with severe night pain and stiffness 3

NSAID Selection

• Common effective options include diclofenac, naproxen, indomethacin, etoricoxib, and celecoxib 4, 5
• Try one NSAID at appropriate dosage before assuming inefficacy 3
• Consider COX-2 selective NSAIDs in patients with higher GI risk 6
• No significant differences in efficacy between traditional NSAIDs and COX-2 inhibitors 2

Safety Considerations

• Monitor for potential side effects:
  • Gastrointestinal: abdominal pain, nausea (most common) 4
  • Cardiovascular risks with long-term use
  • Renal function should be monitored 1
• About 25% of patients report severe side effects from NSAIDs 4
• Consider patient's comorbidities when selecting specific NSAID

Second-Line Therapy (If NSAIDs Fail)

For Axial Disease

• Tumor necrosis factor inhibitors (TNFi) such as adalimumab, etanercept, infliximab, golimumab 1
• Etanercept (Enbrel) is FDA-approved for reducing signs and symptoms in patients with active ankylosing spondylitis 7

For Peripheral Arthritis

• Sulfasalazine is recommended for peripheral arthritis but is not effective for axial disease 1
• Consider sulfasalazine in patients with:
  • High disease activity
  • Peripheral arthritis
  • AS of short duration 3

Non-Pharmacological Treatment

• Regular exercise is essential and should be prescribed alongside medication 1
• Physical therapy focusing on:
  • Maintaining spinal mobility
  • Improving posture
  • Strengthening core muscles
  • Gentle stretching 1
• Supervised exercise programs are preferred over home exercises alone 1

Common Pitfalls to Avoid

• Using systemic glucocorticoids for axial disease (not supported by evidence) 1
• Relying on DMARDs like methotrexate for axial disease (ineffective) 1
• Inadequate NSAID dosing before declaring treatment failure 1
• Neglecting the importance of regular exercise and physical therapy 1

Monitoring Approach

• Regularly assess disease activity using validated measures (BASDAI, BASFI)
• Monitor inflammatory markers (CRP, ESR) at regular intervals
• Assess pain, function, and medication side effects, especially GI, renal, and cardiovascular 1
• Radiographic monitoring generally not needed more frequently than every 2 years unless significant changes in clinical status 1

Remember that while NSAIDs provide symptomatic relief, they may not alter the long-term disease course. About 20% of patients report insufficient pain control with NSAIDs, and more than 40% need to change their NSAID due to lack of efficacy 4. For these patients, prompt escalation to biologics (TNF inhibitors) is warranted.