About polymyalgia rheumatica

Polymyalgia rheumatica (PMR) is an inflammatory disorder that causes widespread muscle aching and stiffness, primarily in your neck, shoulders, upper arms, thighs and hips.

Although some people develop these symptoms gradually, polymyalgia rheumatica can literally appear overnight. People with polymyalgia rheumatica may go to bed feeling fine, only to awaken with stiffness and pain the next morning.

Just what triggers polymyalgia rheumatica isn’t known, but the cause may be a problem with the immune system, perhaps involving both genetic and environmental factors. Aging also appears to play a role.

Polymyalgia rheumatica usually goes away on its own in a year or two. But you don’t have to endure polymyalgia rheumatica for months or years. Medications and self-care measures can improve your symptoms.

Symptoms

Polymyalgia rheumatica symptoms may include:

  • Moderate to severe aching and stiffness in the muscles in your hips, thighs, shoulders, upper arms and neck
  • Fatigue
  • Unintentional weight loss
  • Weakness or a general feeling of being unwell
  • Sometimes, a slight fever
  • Anemia — low red blood cell count

Initially, you may have pain on just one side of your body, but as the disease progresses, symptoms are likely to occur on both sides.

Stiffness is usually worse in the morning or after sitting or lying down for long periods. At times, the discomfort may also be severe enough to wake you at night.

The aching and stiffness of polymyalgia rheumatica often occur suddenly, but sometimes may develop gradually.

Between 10 percent and 20 percent of people with polymyalgia rheumatica have a related condition called giant cell arteritis, which causes the arteries in your temples and sometimes in your neck and arms to become swollen and inflamed.

Causes

Polymyalgia rheumatica is an arthritic syndrome that causes your muscles to feel achy and stiff due to mild inflammation in your joints and surrounding tissues. Most of the inflammation occurs in the hip and shoulder joints, but it may develop elsewhere in your body as well. In general, the inflammation isn’t as severe as that in inflammatory types of arthritis, such as rheumatoid arthritis.

In polymyalgia rheumatica, inflammation occurs when white blood cells — which normally protect your body from invading viruses and bacteria — attack the lining of your joints (synovium). Researchers aren’t sure what causes this abnormal immune system response, but they suspect that as with many disorders, both genetic and environmental factors are involved.

There may be a link between polymyalgia rheumatica and certain viruses, such as adenovirus, which causes respiratory infections ranging from the common cold to pneumonia; human parvovirus B19, the source of an infection that primarily affects children; and human parainfluenza virus.

Although the exact causes of polymyalgia rheumatica are unknown, certain factors may increase your risk of developing the disease, including:

  • Age. Polymyalgia rheumatica affects older adults almost exclusively — the average age at onset of the disease is 70.
  • Sex. Women are twice as likely to develop the condition as men are.
  • Race. Although polymyalgia rheumatica can affect people of any race, the vast majority are white. People of Northern European and Scandinavian origin are particularly at risk.
  • Giant cell arteritis. Also at risk are people with giant cell arteritis, a condition that causes arteries in your temples or sometimes other parts of your body to become swollen and inflamed. As many as half the people with giant cell arteritis also have polymyalgia rheumatica.

Diagnosis

The signs and symptoms of polymyalgia rheumatica are similar to those of a number of other conditions, including rheumatoid arthritis and polymyositis — a disease that causes muscle inflammation and weakness. For that reason, your doctor will want to rule out other possible causes for your pain and stiffness before making a diagnosis of polymyalgia rheumatica.

To aid in the diagnosis, your doctor will interview you about your medical history and current symptoms and conduct a thorough physical exam. You’re also likely to have one or more tests, including:

  • Sed rate. If your doctor suspects polymyalgia rheumatica, he or she will order a blood test that checks your erythrocyte sedimentation rate, commonly known as the sed rate. This test measures how quickly your red blood cells settle when placed in a test tube. Generally, the blood cells fall faster — that is, the sed rate increases — when inflammation is present. But because many conditions can cause inflammation in your body, including infections and chronic diseases, such as rheumatoid arthritis and other rheumatic disorders, an elevated sed rate alone can’t confirm the presence of polymyalgia rheumatica.
  • Rheumatoid factor (RF). RF is an antibody — a protein made by the immune system — that’s often present in the blood of people with rheumatoid arthritis, but not in the blood of people with polymyalgia rheumatica. Consequently, this test can help your doctor distinguish between the two conditions.
  • Other blood tests. Your doctor may also check the number of red blood cells and platelets (thrombocytes) in your blood. Platelets are colorless blood cells that help stop blood loss when you’re injured. Most people with polymyalgia rheumatica have an unusually high number of these cells (thrombocytosis). On the other hand, many people with polymyalgia rheumatica have a lower number of red blood cells than normal and are often anemic.You may also have a simple and inexpensive blood test that checks levels of C-reactive protein in your blood. The protein is produced by your liver as part of a normal immune system response to injury or infection. Among other things, high blood levels of C-reactive protein may indicate the presence of inflammation.

Checking for giant cell arteritis
If you receive a diagnosis of polymyalgia rheumatica, your doctor will check for a related condition called giant cell arteritis, which occurs in some people with polymyalgia rheumatica. Signs and symptoms — such as new headaches, a tender scalp, pain when you chew, visual changes including double vision or visual loss — along with the results of a sed rate test can help determine whether you have this disorder.

The only way to confirm a diagnosis of giant cell arteritis is by taking a small sample (biopsy) from the scalp artery in your temple (temporal artery). The sample is then examined under a microscope in a laboratory. Although polymyalgia rheumatica and giant cell arteritis are both treated with corticosteroids, the recommended dosage for management of giant cell arteritis is higher than for polymyalgia rheumatica. As a result, your doctor will likely recommend confirming the diagnosis of giant cell arteritis with a biopsy.

The most serious complication of polymyalgia rheumatica is giant cell arteritis. The exact relationship between the two conditions isn’t clear, but between 10 percent and 20 percent of people with polymyalgia rheumatica also develop giant cell arteritis and nearly half of those with giant cell arteritis have polymyalgia rheumatica.

Giant cell arteritis causes the lining of arteries to become inflamed and swollen. Arteries are blood vessels that carry oxygen-rich blood from your heart to the rest of your body. Although giant cell arteritis can affect the arteries in your neck, upper body and arms, it occurs most often in the scalp arteries in your temples. Untreated, giant cell arteritis may lead to vision loss, a stroke or an aortic aneurysm, a potentially life-threatening bulge in the large artery that runs down the center of your chest and abdomen.

Polymyalgia rheumatica itself causes few other serious problems, but the corticosteroid drugs used to treat the disease can cause a number of serious side effects, such as weight gain, high blood pressure, osteoporosis, high blood sugar levels and cataracts.

Treatment

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen (Advil, Motrin, others) can be effective in treating mild symptoms of polymyalgia rheumatica. However, long-term use of NSAIDs can cause stomach and intestinal bleeding, fluid retention, high blood pressure, renal insufficiency, worsening congestive heart failure, liver function test abnormalities, and possible cognitive changes.

Corticosteroids
In most cases, the usual polymyalgia rheumatica treatment is a low, daily dose of an oral corticosteroid drug such as prednisone. Relief should be almost immediate. If you’re not feeling better in a few days, it’s likely you don’t have polymyalgia rheumatica. In fact, your response to medication is one way your doctor may confirm the diagnosis.

After the first month, when your sed rate and platelet count have normalized, and any anemia is improved, your doctor will gradually start lowering the amount of cortisone you take until you reach the lowest possible dosage needed to control inflammation. Some of your symptoms may return during this tapering-off period. If so, tell your doctor so that your dosage can be adjusted appropriately.

The amount of time on medication varies from person to person. Most people are able to discontinue steroids within two years. Don’t stop taking this medication on your own, however. Because corticosteroids suppress your body’s natural production of cortisone, stopping suddenly can make you very ill.

At the same time, taking steroids, even in low doses, for long periods can lead to a number of side effects. This is especially true for older adults — those most likely to be treated for polymyalgia rheumatica. That’s because they’re more prone to develop certain conditions that also may be caused by corticosteroids, such as:

  • Osteoporosis. This condition causes bones to become so weak and brittle that even slight movements such as bending over, lifting a vacuum cleaner or coughing can cause a fracture. Older women are most at risk of osteoporosis, and taking steroid medications increases the risk. For this reason, your doctor is likely to monitor your bone density and may prescribe calcium and vitamin D supplements or other medications to help prevent bone loss.
  • High blood pressure (hypertension). Long-term corticosteroid use can also raise blood pressure. Your doctor is likely to monitor your blood pressure and may recommend an exercise program, diet changes and sometimes medication to keep blood pressure within a normal range.
  • Cataracts. Cortisone increases your risk of cataracts, a condition that causes the lens of the eye to become cloudy, impairing vision.

Other possible side effects of cortisone therapy include weight gain, decreased immune system function — making you more prone to infections — muscle weakness and high blood sugar levels, which may increase your risk of diabetes or worsen diabetes you already have.

Because of these risks, researchers are investigating other medications to treat polymyalgia rheumatica. Researchers have reported some success with a combination of the drug methotrexate and corticosteroids, but more research is needed to recommend this approach. In some cases, you and your doctor may decide that the balance of risks and benefits lies in favor of using NSAIDs to control symptoms, rather than corticosteroids.

Self-care

Once you start taking medication for polymyalgia rheumatica, your pain and stiffness should greatly improve. In addition, the suggestions below also can help:

  • Exercise regularly. Exercise can reduce the pain of polymyalgia rheumatica and improve your overall sense of well-being. It can also help prevent weight gain, a common side effect of taking corticosteroids. Emphasize low-impact exercises such as swimming, walking and riding a stationary bicycle. Moderate stretching also is important for keeping your muscles and joints flexible.If you’re not used to exercising, start out slowly and build up gradually, aiming for at least 30 minutes on most days. Your doctor can help you plan an exercise program that’s right for you.
  • Eat a healthy diet. Eating well can help prevent potential problems such as thinning bones, high blood pressure and diabetes. Good nutrition can also support your immune system. Emphasize fresh fruits and vegetables, whole grains, and lean meats and fish, while limiting salt, sugar and alcohol.Get adequate amounts of bone-building nutrients — calcium and vitamin D. If you find it hard to get calcium from your diet because you can’t eat dairy products, for example, try calcium supplements. Experts recommend 1,200 milligrams of calcium and 800 international units (IU) of vitamin D a day.
  • Pace yourself. Try to alternate strenuous or repetitive tasks with easier ones to prevent straining painful muscles. Use luggage and grocery carts, reaching aids, and shower grab bars to help make daily tasks easier.