Polymyalgia Rheumatica Treatment & Management

Polymyalgia rheumatica (PMR) is a chronic, self-limited disorder. Therapy is based on empiric experiences because few randomized clinical trials are available to guide treatment decisions. The therapeutic goals are to control painful myalgia, to improve muscle stiffness, and to resolve constitutional features of the disease.

Corticosteroids (ie, prednisone) are considered the treatment of choice because they often cause complete or near-complete symptom resolution and reduction of the erythrocyte sedimentation rate (ESR) to normal. However, no definite evidence demonstrates that corticosteroids (or any other therapy) alter the natural history of PMR. Before the corticosteroid era, patients with PMR occasionally experienced spontaneous improvements and musculoskeletal symptoms were treated with nonsteroidal anti-inflammatory drugs (NSAIDs). The low-dose corticosteroids used in PMR are almost certainly ineffective in the prevention of vasculitis progression.

A systematic examination of the peer-reviewed literature, which included 30 studies, found that remission of PMR seemed to be achieved for most patients with a starting dose of prednisone at 15 mg/day. A slow tapering of the prednisone, less than 1 mg/month, was associated with fewer relapses. Once prednisone is tapered to 10 mg/day, a slow taper by 1 mg every 2 months until treatment discontinuation was associated with optimal control of disease activity.^[15]

Nevertheless, controversy remains regarding dose and duration of treatment. Dose depends on the patient's weight and severity of symptoms. Expect prompt relief of symptoms within 24-72 hours. Corticosteroid dose should be increased if symptoms are not well controlled within 1 week, and a diagnosis of giant cell arteritis may need to be pursued, especially if prednisone 20 mg/d does not control symptoms.

Tapering should be guided by clinical response, to include decreased pain and stiffness, decreased morning stiffness, and decreased shoulder pain/limitation on clinical examination.^{[16, 17]} Normalization of inflammatory markers is also helpful but should not set the guidelines for decreasing or stopping treatment. In contrast to other rheumatic diseases, alternate-day administration of corticosteroids in PMR has largely been unsuccessful.

If not contraindicated, NSAIDs may provide supplemental pain relief. However, per a study of 232 patients with PMR by Gabriel and colleagues, NSAIDs are associated with considerable drug-related morbidity and thus should be used with caution.^[18]

Corticosteroid-sparing agents are sometimes considered in patients with PMR to reduce corticosteroid-related adverse effects, especially in certain patient populations such as diabetic patients or in those who develop osteonecrosis.

Methotrexate has been investigated in 3 randomized studies in newly diagnosed PMR. One study used methotrexate at 7.5 mg/week plus 20 mg/day of prednisone and found no benefit in outcomes after 2 years of follow-up.^[19] Another study used oral and intramuscular methotrexate at a higher dose of 10 mg/week added to the prednisone regimen versus prednisone regimen alone. Overall, the patients receiving methotrexate 10 mg/week plus prednisone experienced corticosteroid-sparing effects compared with patients receiving prednisone alone.^{[20, 21]}

Antitumor necrosis factor alpha (anti-TNF) agents have also been investigated as corticosteroid-sparing agents in PMR. A randomized study with infliximab revealed no benefit.^[22] The only randomized trial using azathioprine (150 mg/d) during the maintenance phase of PMR showed a high frequency of adverse drug effects, a high number of patient withdrawal from the study, although a lower cumulative dose of corticosteroid at 52 weeks. At this time, the small number of completers and the high number of giant cell arteritis patients in the study make the study results difficult to interpret.^[23]

More studies are needed to better determine if steroid-sparing agents should be recommended in PMR.^[15]

Symptomatic palliation of pain with analgesic therapy alone with close monitoring may be preferable in patients with intolerable adverse effects from corticosteroids (eg, uncontrolled diabetes mellitus, severe symptomatic osteoporosis, psychosis).

Diagnosis and treatment involve the primary care physician and rheumatologist. Ophthalmologists, pathologists, and surgeons may be consulted on an as-needed basis should concern arise about the development of giant cell arteritis. In coordination with the primary care physician, the rheumatologist plays an important role in diagnosis, treatment, and follow-up care. Primary care providers are imperative to assist with the management of comorbidities such as prophylaxis for cardiovascular disease, glucocorticoid-induced hyperglycemia, and osteoporosis. Appropriate immunizations should be administered, ideally before corticosteroid therapy is initiated.

Polymyalgia rheumatica is typically treated in an outpatient setting. Objective means of determining prognosis and decisions concerning duration of treatment remain empiric and patients often need careful supervision.

Patients receiving steroids should have monthly follow-up, with regular monitoring of inflammatory markers. An isolated increase of ESR without symptoms during the course of treatment is not a valid reason to increase corticosteroid dose; however, a temporary delay in dosage reduction may be necessary. After steroid tapering, follow-up can be performed quarterly.

The risk of vertebral fractures is 5 times greater in women with polymyalgia rheumatica.^[4] As such, calcium and vitamin D supplementation should be initiated in all patients with polymyalgia rheumatica who are starting corticosteroid therapy. A baseline bone mineral density study (eg, dual-energy x-ray absorptiometry [DEXA] scan) is recommended at the onset of treatment. As most patients require corticosteroids for at least 1-2 years, bisphosphonate therapy is recommended to prevent corticosteroid-induced osteoporosis.

Because relapses are more likely to occur during the initial 18 months of therapy and within 1 year of corticosteroid withdrawal, with a frequency of approximately 50%, all patients should be monitored for symptom recurrence throughout corticosteroid tapering and until 12 months after cessation of therapy. Relapses usually occur when the dose of prednisone is less than 5-7.5 mg/d or after therapy had been discontinued. If symptoms recur, the corticosteroid dose should be increased to the dose that previously controlled the symptoms. Recurrences of the disease more than 1 year after discontinuation of corticosteroid therapy has been reported.^[24]

Approximately 50-75% of patients can discontinue corticosteroid therapy after 2 years of treatment. However, some patients may require low doses of corticosteroids for several years.

Patients with polymyalgia rheumatica should be monitored regularly and carefully for symptoms and signs suggestive of giant cell arteritis development.