From the Guidelines
Polymyalgia rheumatica (PMR) should be diagnosed based on clinical presentation of bilateral shoulder and hip girdle pain and stiffness in patients over 50 years old, along with elevated inflammatory markers (ESR >40 mm/hr or CRP >10 mg/L), and treated with low-dose oral prednisone, typically starting at 12.5-25 mg daily, as recommended by the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) collaborative initiative 1. The diagnosis of PMR is primarily clinical, relying on the presence of characteristic symptoms and elevated inflammatory markers.
- Key diagnostic features include:
- Bilateral shoulder and hip girdle pain and stiffness
- Elevated ESR (>40 mm/hr) or CRP (>10 mg/L)
- Age over 50 years
- The treatment approach should be individualized, considering factors such as comorbidities, risk of relapse, and potential side effects of glucocorticoids (GCs).
- The initial GC dose should be within the range of 12.5-25 mg prednisone equivalent daily, with a higher dose considered in patients at high risk of relapse and a lower dose in those with significant comorbidities or risk factors for GC-related side effects 1.
- Patients usually experience rapid symptom improvement within 24-72 hours, which can serve as a diagnostic confirmation.
- After 2-4 weeks of initial therapy with a good response, the dose should be gradually tapered by 1-2.5 mg every 2-4 weeks, aiming for the lowest effective dose.
- Regular monitoring of inflammatory markers (ESR or CRP) is crucial to guide tapering decisions and prevent relapse.
- Calcium (1000-1200 mg daily) and vitamin D (800-1000 IU daily) supplementation should be initiated concurrently with steroids to prevent osteoporosis, and bisphosphonates may be indicated for those at high fracture risk 1.
- Steroid-sparing agents like methotrexate (10-15 mg weekly) may be considered in patients with frequent relapses or steroid-related complications.
- Patients should be monitored for symptoms of temporal arteritis (headache, jaw claudication, visual changes), which requires immediate medical attention to prevent blindness.
- The management of PMR should also consider the patient's overall health, including the assessment of comorbidities and the risk of GC-related side effects, as emphasized in the 2015 EULAR/ACR recommendations 1.
From the Research
Diagnosis of Polymyalgia Rheumatica
- The diagnosis of polymyalgia rheumatica (PMR) is based on clinical symptoms, such as inflammatory pain in the shoulder and/or pelvic girdles, and elevated laboratory tests, including C-reactive protein and erythrocyte sedimentation rates 2, 3.
- Imaging studies, such as ultrasonography and magnetic resonance imaging (MRI), can aid in the diagnosis of PMR 2, 3.
- It is essential to differentiate PMR from other conditions that may mimic its symptoms, including giant cell arteritis, elderly onset rheumatoid arthritis, and other rheumatologic diseases 2, 3.
Treatment of Polymyalgia Rheumatica
- Glucocorticoids are the mainstay of treatment for PMR, with an initial dose of 12.5-25 mg prednisone equivalent daily 4, 3.
- The optimal starting dosage and tapering schedule of glucocorticoids are not agreed upon, but a low starting dosage and slow tapering may decrease the relapse rate 4, 5.
- Methotrexate can be used as an adjuvant therapy in patients with glucocorticoid dependency or resistance 4, 6, 5.
- Tocilizumab has been shown to be effective in treating glucocorticoid-resistant PMR 6, 5.
- The treatment duration for PMR is typically 2-3 years, but may be longer in some cases 3.
Glucocorticoid Tapering
- A slow tapering regimen from a low initial steroid dose (between 10 and 20 mg) is recommended to minimize the risk of relapse and steroid-induced adverse events 4, 5.
- Individualization and close monitoring are essential during the steroid-tapering process 5.
- The use of steroid-sparing agents, such as methotrexate, tocilizumab, and sarilumab, may help reduce the risk of relapse and steroid-induced adverse events 6, 5.