What is the role of corticosteroids (e.g. prednisone) in the management of Polymyalgia Rheumatica (PMR)?

Role of Corticosteroids in Polymyalgia Rheumatica Management

Corticosteroids are the cornerstone of treatment for Polymyalgia Rheumatica (PMR), with an initial recommended dose of 12.5-25 mg daily prednisone, followed by a structured tapering regimen to minimize side effects while maintaining disease control. 1, 2

Initial Treatment Approach

Starting Dose

• Initial prednisone dose should be 12.5-25 mg daily (single morning dose before 9 am)
• Lower doses (≤7.5 mg/day) are insufficient for symptom control
• Higher doses (>30 mg/day) are strongly discouraged due to increased adverse effects
• Clinical response typically occurs within 7 days of starting therapy 3

Tapering Schedule

1. Reduce to 10 mg/day within 4-8 weeks
2. Then gradually reduce by 1 mg every 4 weeks until discontinuation
3. Tapering too quickly (>1 mg/month) increases relapse risk 2

Monitoring and Follow-up

• Follow-up visits every 4-8 weeks in first year
• Every 8-12 weeks in second year
• More frequent monitoring during relapses or tapering periods
• Monitor for:
  • Disease activity (symptoms)
  • Laboratory markers (ESR, CRP)
  • Steroid-related side effects 1, 2

Managing Relapses

If relapse occurs during tapering:

1. Increase prednisone to pre-relapse dose
2. Gradually decrease (within 4-8 weeks) to the dose at which relapse occurred
3. Resume slower tapering when symptoms are controlled 2

Steroid-Sparing Agents

Methotrexate

• Most effective steroid-sparing agent for PMR
• Dosage: 7.5-10 mg/week orally
• Indications:
  • High risk for relapse or prolonged therapy
  • Risk factors for glucocorticoid-related adverse events
  • Patients who have experienced a relapse
  • Inadequate response to glucocorticoids
  • Patients experiencing glucocorticoid-related adverse events 2, 4

Intramuscular Methylprednisolone

• Alternative to oral prednisone
• Structured dosing regimen starting at 120 mg every 3 weeks 2

Risk Stratification

Risk Factors for Relapse/Prolonged Therapy

• Female sex
• High ESR (>40 mm/1st hour)
• Peripheral inflammatory arthritis 1, 2

Heterogeneity in Treatment Response

Research has identified three distinct patient groups based on treatment response 5:

1. Rapid responders: Low ESR, require corticosteroids for <1 year
2. Partial responders with prolonged course: Good initial response but require >1 year of therapy
3. Partial responders: Higher pretreatment pain scores, persistently elevated IL-6 despite ESR improvement

Special Considerations

When to Consider Specialist Referral

• Atypical presentation (peripheral inflammatory arthritis, systemic symptoms, low inflammatory markers, age <60 years)
• High risk of or experiencing therapy-related side effects
• PMR refractory to glucocorticoid therapy
• Relapses or need for prolonged therapy 1

Non-Recommended Treatments

• NSAIDs are not recommended as primary treatment (only for short-term use for pain related to other conditions)
• TNFα blocking agents are not recommended
• Chinese herbal preparations (Yanghe and Biqi capsules) are not recommended 1, 2

Comprehensive Management

• Patient education about PMR and its treatment is crucial
• Individualized exercise program to maintain muscle mass and function
• Regular assessment for steroid-related complications
• Osteoporosis prophylaxis is recommended 2, 3

Pitfalls to Avoid

• Inadequate initial dosing leading to poor symptom control
• Too rapid tapering causing frequent relapses
• Failure to recognize PMR complications like giant cell arteritis
• Overlooking steroid-related adverse effects
• Missing alternative diagnoses in atypical or non-responsive cases 1, 6