Polymyalgia Rheumatica (PMR)

Muscle pain and joint stiffness are symptoms of polymyalgia rheumatica.

Polymyalgia rheumatica is a disease of the muscles and joints characterized by muscle pain (myalgia) and stiffness, affecting both sides of the body, and involving the shoulders, arms, neck, and buttock areas. People with the disease are typically over 50 years of age. Polymyalgia rheumatica is abbreviated PMR.

PMR and temporal arteritis (giant cell arteritis) sometimes occur in the same patient. About 10%-15% of people with PMR also have giant cell arteritis.

The cause of the condition is not known. Recent research has indicated that genetic (inherited) risk factors play a role in who becomes afflicted with the illness. Theories include viral stimulation of the immune system in genetically susceptible individuals. Rarely, the disease is associated with a cancer. In this setting, the cancer may be initiating an inflammatory immune response to cause the polymyalgia rheumatica symptoms.

The onset of the disease can be sudden. A patient may have a healthy history until awakening one morning with stiffness and pain of muscles and joints throughout the body, particularly in the upper arms, hips, neck, and shoulders. These pains can lead to a sensation of weakness and loss of function. Sometimes there is also muscle tenderness with PMR. These clinical symptoms persist and often include an intense sensation of fatigue. Some patients notice a gradual loss of appetite accompanied by weight loss and lack of energy. Depression can occur.

The diagnosis of the disorder is suggested by the health history and physical examination. A health care professional frequently notes muscle tenderness and that the motion of the shoulders is limited by pain. The joints are usually not swollen. However, signs such as swelling of the small joints of the hands, wrists, and/or knees can occur. Blood testing for inflammation is generally abnormal, as indicated by a significant elevation in the erythrocyte sedimentation rate (sed rate or ESR) and/or C-reactive protein. There are no specific tests, however, for the condition and X-rays are normal. The diagnosis is based on the characteristic history of persisting muscle and joint pain and stiffness associated with elevated blood tests for inflammation, such as the ESR. It is also not unusual for patients to have slight elevations of liver blood tests.

Doctors direct their medical treatment of PMR toward reducing pain and inflammation. While some patients with mild symptoms can improve with nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen (Motrin, Advil), most patients respond best to low doses of corticosteroids (such as prednisone or prednisolone). Not infrequently, a single day of cortisone medicine eases many of the symptoms! In fact, the rapid, gratifying results with low dose corticosteroids is characteristic of the condition.

The corticosteroid dose is gradually reduced while the doctor monitors the symptoms and normalization of the blood ESR. Reactivation of symptoms can require periodic adjustments in the prednisone dosage. Most patients are able to completely wean from the corticosteroid within several years. Some patients require longer-term medical treatment. Occasionally, patients have recurrence years after the symptoms have resolved. The ideal prednisone dosing regimen continues to be sought by clinical researchers.

Polymyalgia rheumatica can lead to loss of function of joints if untreated. This generally is temporary, but frozen shoulders can be a further medical complication. Additional complications can result from medications used to treat polymyalgia rheumatica. These include stomach bleeding or kidney impairment from nonsteroidal anti-inflammatory drugs and cataracts, bruising of skin, and osteoporosis from cortisone medications. Therefore, the lowest possible doses of medications are best.

Polymyalgia rheumatica can occur in association with giant cell arteritis (temporal arteritis). Giant cell arteritis is a potentially more serious condition. It can also occur, as mentioned above, in association with a cancer. The prognosis in this setting is based on the ability to cure the cancer. The polymyalgia rheumatica symptoms resolve with resolution of the cancer.

The outlook for patients with isolated polymyalgia rheumatica is ultimately very good.

One of the keys to successful treatment of polymyalgia rheumatica is gradual, and not rapid, tapering of the medicines. This can avoid unwanted flare-ups of the disease.

Because the medicines prednisone and prednisolone are associated with potential bone toxicity, causing osteoporosis, patients should consider calcium and vitamin D supplementation. Bone mineral density testing should be performed in appropriate patients, and doctors may consider prescribing osteoporosis medicines, such as estrogen, alendronate (Fosamax), and risedronate (Actonel) for some.

There is no prevention for polymyalgia rheumatica. Prevention measures focus on preventing side effects of drugs used to treat polymyalgia rheumatica.