PMR causes moderate to severe aching and stiffness in the muscles of the hips, thighs, shoulders, upper arms and neck. Most people have pain in at least two of these areas. At first, pain may be present on just one side of the body, but as the disease continues, symptoms are likely to occur on both sides.
Stiffness is usually worse in the morning. Trying to move without pain can leave those with PMR exhausted for the rest of the day, and pain may also be bad enough to awaken them at night.
Sometimes the aching and stiffness develop suddenly. In other cases, they appear more gradually.
Other signs include:
- Weight loss
- Slight fever
Causes and Risk Factors
The exact causes of PMR are not known. The inflammation that causes the pain occurs when white blood cells, which normally protect the body from invading viruses and bacteria, attack the lining of the joints, particularly the shoulders, hips and knees. PMR is usually less severe than rheumatoid arthritis.
Risk factors include:
- Age - The average age of persons with this disease is 70.
- Gender - Women are two times more likely to develop the condition than are men.
- Ethnicity - Although people of any race can develop PMR, those most often affected are of Northern European or Scandinavian decent.
- Other health conditions - Including giant cell arteritis. This condition causes the arteries in the temples to become swollen and inflamed. Half the people with giant cell arteritis also have PMR.