Diagnosis and Treatment of Polymyalgia Rheumatica
Diagnosis
PMR should be suspected in patients over 60 years old presenting with bilateral shoulder and hip girdle pain and morning stiffness lasting more than 45 minutes, accompanied by elevated inflammatory markers (ESR >40 mm/hr or elevated CRP). 1
Key Diagnostic Features:
- Age ≥60 years is a critical criterion; younger patients warrant specialist referral for atypical presentation 1
- Bilateral shoulder and hip girdle pain with morning stiffness is the hallmark symptom 1
- Elevated ESR (>40 mm/1st hour) or CRP supports the diagnosis, though low inflammatory markers should prompt consideration of alternative diagnoses 1
- Rapid response to glucocorticoids (within 7 days) is highly characteristic; lack of response to 20 mg/day prednisone suggests an alternative diagnosis 2
When to Refer to Specialist:
Refer patients with any of the following 1:
- Peripheral inflammatory arthritis
- Systemic symptoms beyond typical PMR
- Low or normal inflammatory markers
- Age <60 years
- Poor response to appropriate glucocorticoid therapy
- Frequent relapses or need for prolonged therapy
- High risk of or existing glucocorticoid-related adverse effects
Initial Treatment
Start prednisone at 12.5-25 mg daily as first-line therapy, with the specific dose individualized based on body weight, relapse risk, and comorbidity profile. 3
Dose Selection Algorithm:
Use 20-25 mg/day for patients with 3:
Use 12.5-15 mg/day for patients with 3:
- Relevant comorbidities (diabetes, osteoporosis, glaucoma)
- Lower body weight 4
- Risk factors for glucocorticoid-related side effects
Avoid doses ≤7.5 mg/day (insufficient anti-inflammatory effect) 1, 3
Never use doses >30 mg/day (excessive adverse effect risk without added benefit) 1, 3
Alternative Route:
- Intramuscular methylprednisolone (120 mg every 3 weeks) can be considered as an alternative to oral glucocorticoids 3
Expected Response:
- Clinical improvement should occur within 7 days 2
- If no response to 20 mg/day within this timeframe, reconsider the diagnosis 2
Glucocorticoid Tapering Schedule
Taper prednisone to 10 mg/day within 4-8 weeks, then reduce by 1 mg every 4 weeks until discontinuation, provided remission is maintained. 1, 3
Initial Tapering Phase (First 4-8 weeks):
- Reduce from starting dose to 10 mg/day prednisone 1, 3
- Monitor clinical symptoms and inflammatory markers (ESR, CRP) at each adjustment 3
Maintenance Tapering Phase (After reaching 10 mg/day):
- Decrease by 1 mg every 4 weeks 1, 3
- Alternative: Use alternating schedules (e.g., 10/7.5 mg every other day) for smoother transitions 3
- Aim for 7.5 mg maintenance dose by 6-9 months 5
Duration of Therapy:
- Most patients require 2 years of treatment, though some need 4 years or longer 5
- Relapses are common when dose reaches ≤5 mg/day 2
Management of Relapses
For relapse, increase prednisone to the pre-relapse dose, then taper more slowly (over 4-8 weeks) back to the dose at which relapse occurred, followed by reduction of 1 mg per month. 6, 3
Relapse Management Algorithm:
- Increase dose immediately to the pre-relapse dose that controlled symptoms 6, 3
- Maintain this dose until symptoms resolve and inflammatory markers normalize 6
- Taper over 4-8 weeks back down to the dose at which relapse occurred 6, 3
- Resume tapering at 1 mg per month (slower than initial taper) 6
Special Consideration for Low-Dose Relapses:
- For patients relapsing on ≤5 mg/day with persistent nighttime pain, consider splitting the daily dose rather than increasing total dose 3
Glucocorticoid-Sparing Agents
Add methotrexate 7.5-10 mg weekly for patients with frequent relapses, prolonged therapy requirements, or significant glucocorticoid-related adverse effects. 3
Indications for Methotrexate:
- Multiple or frequent relapses 6, 3
- High risk factors for relapse (female sex, ESR >40, peripheral arthritis) 1, 3
- Risk factors for glucocorticoid adverse events (diabetes, osteoporosis, glaucoma) 3
- Existing glucocorticoid-related complications 3
- Inadequate response to glucocorticoids alone 3
Agents to Avoid:
- TNF-α blocking agents (infliximab, etanercept) are strongly contraindicated—they are ineffective in isolated PMR 3, 7
- Chinese herbal preparations (Yanghe, Biqi capsules) should not be used 3
Emerging Therapies:
- Tocilizumab and sarilumab (anti-IL-6 receptor agents) show promise for reducing relapse frequency and cumulative glucocorticoid burden, though they are not yet standard therapy 7
Monitoring and Follow-Up
Schedule visits every 4-8 weeks during the first year, every 8-12 weeks in the second year, and as needed for relapses or dose adjustments. 1, 3
At Each Visit, Assess:
- Clinical symptoms (pain scores, morning stiffness duration) 1
- Inflammatory markers (ESR, CRP) 6, 3
- Glucocorticoid-related adverse effects 1, 3:
- Bone mineral density (osteoporosis screening)
- Blood glucose (diabetes screening)
- Blood pressure (hypertension)
- Ocular examination (cataracts, glaucoma)
- Risk factors for relapse (female sex, high ESR, peripheral arthritis) 1
- Comorbidities and concurrent medications 1
Patient Access:
- Ensure rapid access to medical advice for reporting flares or adverse events between scheduled visits 1
Adjunctive Measures
Osteoporosis Prophylaxis:
Patient Education:
- Provide education on disease impact, treatment expectations, and comorbidity management 1
- Recommend individually tailored exercise programs 1