What is the treatment for polymyalgia rheumatica (PMR)?

Treatment for Polymyalgia Rheumatica (PMR)

The cornerstone treatment for polymyalgia rheumatica is oral glucocorticoids (GCs), with an initial prednisone dose of 12.5-25 mg/day, followed by a gradual tapering schedule over time, and methotrexate should be considered as a steroid-sparing agent in patients at high risk for relapse or GC-related adverse events. 1, 2

Initial Glucocorticoid Therapy

Starting Dose and Administration

• Initial prednisone dose should be between 12.5-25 mg/day 1, 2
• Doses ≤7.5 mg/day are discouraged as they may be insufficient
• Doses >30 mg/day are strongly discouraged due to increased risk of adverse effects without additional benefit 1
• Single daily doses are preferred over divided doses, except in cases of prominent night pain when tapering below 5 mg daily 1
• Alternative option: Intramuscular methylprednisolone (120 mg every 3 weeks) may be considered instead of oral prednisone 1

Initial Response

• Clinical improvement should occur within 7 days of starting therapy 3
• Lack of response to 20 mg/day of prednisone should prompt consideration of alternative diagnoses 3

Tapering Schedule

Initial Tapering

• Taper to 10 mg/day within 4-8 weeks of starting treatment 1
• For conditions requiring initial high-dose therapy, tapering should occur over 6-8 weeks 2

Maintenance and Further Tapering

1. Once remission is achieved, taper prednisone by 1 mg every 4 weeks (or by using alternate day schedules such as 10/7.5 mg) 1
2. Continue tapering until discontinuation as long as remission is maintained
3. A prolonged period at 5 mg/day (approximately one year) before further tapering may help prevent relapses 4, 5

Relapse Management

• If relapse occurs: Increase prednisone to the pre-relapse dose
• Then gradually decrease (within 4-8 weeks) to the dose at which relapse occurred 1
• Continue monitoring and resume tapering once symptoms are controlled

Steroid-Sparing Agents

Methotrexate

• Conditionally recommended for early introduction in addition to GCs in:
  • Patients at high risk for relapse
  • Those requiring prolonged therapy
  • Patients with risk factors or comorbidities that increase risk of GC-related adverse events 1
• Dosage: 7.5-10 mg/week orally 1, 6
• Benefits: Associated with shorter prednisone treatment duration, fewer flare-ups, and lower cumulative prednisone dose 6

Other Medications

• TNFα blocking agents are strongly discouraged for PMR treatment 1
• Chinese herbal preparations Yanghe and Biqi capsules are strongly discouraged 1
• NSAIDs are not recommended as primary treatment but may be used for short-term symptom management 2
• Anti-IL-6 receptor agents (tocilizumab, sarilumab) show promise but are not currently recommended in guidelines 2, 5

Monitoring and Follow-up

• Regular monitoring of disease activity, laboratory markers, and adverse events is essential 1
• Morning serum cortisol testing can assess HPA axis recovery 2
• Consider ACTH stimulation testing for patients with prolonged therapy or symptoms of adrenal insufficiency 2
• Provide stress dose education for patients on long-term therapy 2

Special Considerations

Exercise

• An individualized exercise program is conditionally recommended to:
  • Maintain muscle mass and function
  • Reduce risk of falls, especially in older patients on long-term GCs 1

Osteoporosis Prevention

• Osteoporosis prophylaxis is recommended for patients on long-term glucocorticoid therapy 3

Pitfalls and Caveats

1. Heterogeneity of disease response: PMR is heterogeneous, with variations in treatment duration and corticosteroid doses required 7
2. Misdiagnosis: Atypical presentation or poor response to initial therapy should prompt consideration of alternative diagnoses 3
3. Steroid-related adverse effects: Mortality during the first year is significantly higher in patients treated with high doses of systemic corticosteroids (>40 mg daily) 2
4. Relapses: Common when prednisone dose is ≤5 mg/day, requiring careful monitoring during this phase of tapering 3
5. Prolonged therapy: Some patients may require treatment for several years, increasing risk of adverse effects 7