Like most people, you've probably experienced stiff and sore muscles occasionally — maybe after a strenuous hike or a weekend of yardwork. Now imagine feeling that way all of the time. That's what it's like to live with polymyalgia rheumatica (PMR), 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 almost always develops in people age 50 and older.
Polymyalgia rheumatica usually goes away on its own in a year or two — often as mysteriously as it came. But you don't have to endure the pain and disabling effects of polymyalgia rheumatica for months or years. Medications and self-care measures can improve your symptoms.
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.
Risk Factor :
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 two times 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 of people with giant cell arteritis also have polymyalgia rheumatica.
When to seek medical advice
See your doctor if you suspect you have polymyalgia rheumatica. Some people delay getting medical care because they think it's normal to have aching and stiffness as they grow older. But persistent pain is never normal. And because doctors can successfully treat polymyalgia rheumatica, you can be spared months or even years of unnecessary discomfort and disability.
Polymyalgia rheumatica causes moderate to severe aching and stiffness in the muscles in your hips, thighs, shoulders, upper arms and neck. 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 also may be severe enough to wake you at night.
The aching and stiffness of polymyalgia rheumatica often occur suddenly, but sometimes may develop gradually. Polymyalgia rheumatica can cause other signs and symptoms including :
- Unintentional weight loss
- Weakness or a general feeling of being unwell
- Sometimes, a slight fever
- Anemia (low red blood cell count)
In the United States, approximately 15 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.
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 diagnose polymyalgia rheumatica only after ruling out other possible causes for your pain and stiffness.
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 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. For that reason, 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 and pain when you chew, 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. Because polymyalgia rheumatica and giant cell arteritis are both treated with corticosteroids, your doctor may simply suggest beginning treatment, rather than perform a biopsy.
The most serious complication of polymyalgia rheumatica is giant cell arteritis. The exact relationship between the two conditions isn't clear, but up to 15 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.
Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen (Advil, Motrin, others) can be effective in treating mild symptoms of polymyalgia rheumatica, although long-term use 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.
For more severe cases, the usual treatment for polymyalgia rheumatica 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.
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. For that reason, 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. People on this combination were able to stop taking steroids sooner.