Polymyalgia Rheumatica (PMR) is an inflammatory disease of muscles that almost only occurs among people over 50-years-old. It causes muscle aches and stiffness. Its cause is unknown, but surely related to both genetic and environmental factors that haven’t been identified.
The symptoms of PMR are muscle aches and stiffness, mainly of the shoulders, neck, and hips. Symptoms are worse in the morning, and ease up as a person moves around during the day. We don’t consider the possibility unless a person has early morning symptoms lasting at least 30 minutes, going on for at least 2 weeks. Muscles are not usually tender, and even though a person may say they “feel weak,” we don’t find true weakness on examination.
There are no good tests for PMR in and of itself. We’d only diagnose it if the blood tests for Sedimentation Rate (ESR) and/or CRP are elevated. These identify inflammation from any cause, but if they’re normal, we’d doubt PMR as a diagnosis. There may also be a mild Anemia of Chronic Disease. If the blood tests are normal, but the history sounds very convincing, we might order an ultrasound of the shoulders to look for bursitis, tendonitis, or joint thickening (synovitis).
Treatment consists of steroids (usually prednisone). This can cause many side effects in the long run (over a month), some serious. But they work amazingly well; anyone who doesn’t feel a lot better after 3-4 days of low-dose treatment (10-20 mg per day) doesn’t have PMR.
The danger of PMR is if a person also has Temporal Arteritis, which can cause blindness. Most patients don’t, but half might develop it eventually. Temporal Arteritis causes new daily headaches, and sometimes an achy jaw while speaking or chewing. So we question PMR patients about such symptoms, and tell them to let us know, especially if we decrease or stop the dose of steroids eventually.