Polymyalgia Rheumatica Versus Rheumatoid Arthritis

Although they may seem similar, polymyalgia rheumatica and rheumatoid arthritis are actually two separate diseases. But how do you know what you're dealing with when you feel pain and stiffness that usually occurs in the morning? Here are the main differences between the two conditions:

Rheumatoid Arthritis:

  • Targets the joints.
  • Can affect people of any age, although shows up most often in the early forties and hits women disproportionately.
  • Pain and stiffness usually occur in the fingers, wrists, and balls of feet.
  • You may also feel fatigued or depressed.
  • Symptoms develop gradually.
  • Diagnosis may be difficult; there is no single test for rheumatoid arthritis.
  • The condition is chronic and may not respond well to medication.
  • It affects about one in 100 people.

Polymyalgia Rheumatica:

  • Targets the muscles.
  • Affects only adults over 50, mainly women. The average age of onset is 70.
  • Pain and stiffness can affect thighs, buttocks, upper arms, and neck.
  • Symptoms come on quickly, sometimes literally overnight.
  • The condition responds quickly to corticosteroids and usually goes away on its own in a year or two.
  • It affects about one in 2,000 people.

Diagnosing polymyalgia rheumatica usually involves running several tests. One of these, a sed rate test, checks the speed with which your red blood cells settle after being placed in a test tube. Generally, if there's inflammation in your body, the cells will fall more quickly. However, other inflammatory diseases can cause the same result, so a rheumatoid factor test may be ordered. This test can tell if a particular protein is present in the blood, which would indicate rheumatoid arthritis. You may also be tested for your platelet count, as most people with polymyalgia rheumatica have elevated platelets. And if you have a smaller number of red blood cells than expected, that can also indicate polymyalgia rheumatica.

If you are found to have polymyalgia rheumatica, your doctor may check to see if you also have a condition known as giant cell arteritis, which often goes hand in hand with polymyalgia rheumatica. Giant cell arteritis causes inflammation of the arteries leading in and out of the head, and it can cause changes in or loss of vision. Symptoms of giant cell arteritis include headaches, scalp tenderness, pain during chewing, and visual disturbances. It is treatable with steroids.



Sources:

Mayo Clinic
www.mayoclinic.com

American College of Rheumatology
www.rheumatology.org

Women's Health For Life by Donnica Moore, MD, Dorling Kindersley (2009)