Polymyalgia rheumatica
By the faculty of Harvard Medical School for The Harvard Medical School Adviser

Q: For weeks now I've been feeling very stiff and sore in my hips and shoulders, especially in the morning. My doctor says I don't have arthritis. What else could it be?

A: Anyone over age 50 is probably used to a little joint stiffness and muscle soreness the morning after a tough workout or some heavy gardening. Generally, a hot shower, massage or good night's rest will get you back to normal. But if there's no good explanation for your discomfort and it keeps coming back, you may have a condition known as polymyalgia rheumatica (PMR).

PMR causes aching and stiffness in the neck, shoulders and hips (see illustration). It affects mainly adults in their 60s and 70s and is rarely diagnosed in people younger than 50. The disorder is twice as likely to occur in women and is more common in whites than in blacks. Among Caucasians, PMR is about as common as rheumatoid arthritis, affecting nearly 1 percent of people over age 50.

The pain and stiffness that are typical in PMR generally occur in the muscles and soft tissues of the shoulders and hips. Irritation also occurs in the small, fluid-filled sacs called bursa that cushion tendons where they attach to bones. The aching and stiffness usually last 30 minutes or more. It's usually worse first thing in the morning, or after you haven't moved for a while. Even turning over in bed may be painful. And the discomfort often wakes people up during the night. Some people with PMR also have flu-like symptoms, including low-grade fever, fatigue and weight loss.

PMR isn't life-threatening. But it can seriously limit your daily activities and take a heavy toll on your sleep and well-being. PMR may come on gradually over days or weeks, but it often appears suddenly. Left untreated, the condition may last for months to years before subsiding gradually. But with proper diagnosis and treatment, the symptoms can be eased almost as quickly as they appear.

Unfortunately, there is no sure-fire way to diagnose PMR. To make the diagnosis, a clinician will review a your health history and perform a physical exam. The most useful lab test is the erythrocyte sedimentation rate (ESR). Most PMR patients have ESRs higher than 40mm/hour. But because many other conditions can raise the ESR and cause symptoms similar to PMR, doctors may decide to perform tests to rule out other possible causes, such as rheumatoid arthritis, fibromyalgia, or an infection. Doing so may require several lab tests and x-rays.

PMR often disappears on its own within a few years. Drugs such as aspirin and ibuprofen can help with mild symptoms. But PMR generally responds best to very low doses of corticosteroid medications ("steroids," for short), such as prednisone. In fact, symptoms improve almost overnight. This rapid response helps confirm a PMR diagnosis: If low doses of steroids don't help dramatically, PMR is probably not responsible for your symptoms. But if you do improve, you can gradually reduce your dose. However, a relapse is likely if your treatment is stopped too soon. Most people need to continue taking a very low dose of prednisone for six months to two years.

PMR is not dangerous in itself. But it also occurs in people who have a more serious problem called giant cell arteritis (GCA). In this condition, the lining of arteries in the head, neck and arms becomes inflamed. As a result, the arteries can narrow, causing symptoms such as headache (especially around the temples, which may be tender to the touch), scalp tenderness and pain or weakness in the jaw. The most common dangerous complication of GCA is blindness. But this almost never occurs if the condition is recognized and treated promptly. The only sure way to diagnose GCA is with a surgical biopsy of the temporal artery. Steroid therapy is very effective, but high doses are required.

PMR occurs in about 50 percent of people who have GCA. On the other hand, only 15 percent of people with PMR actually have GCA. Since PMR is so much more common than GCA, most doctors don't recommend temporal artery biopsies or high-dose steroids for their PMR patients unless they have clinical findings that suggest GCA.

Long-term, high-dose steroid treatment has many side effects. But the low doses used in treating PMR rarely cause problems. When you take steroids, it's important for your clinician to properly monitor the effects and taper the dose. You can expect to feel fine while you're being treated for PMR -- and you can expect to stay well after your therapy is completed.

Despite its fierce name, PMR is a mild condition that responds well to treatment.

Copyright 2006 the President and Fellows of Harvard College. Developed by Harvard Health Publications (www.health.harvard.edu). Distributed by UFS. Submit q u e s t i o n s t o harvard_adviser@hms.harv ard.edu.