Polymyalgia rheumatica (PMR) is an inflammatory condition that causes pain and stiffness in the shoulders and the hips. The pain and stiffness is usually much worse in the mornings and fatigue is also quite common.
The cause of Polymyalgia Rheumatica is not well understood. Some theories propose that it might be caused by an external factor like a virus that stimulates the immune system to behave in an undesirable way.
In about half of people who get Polymyalgia Rheumatica, it's a self-limited disease, which means it goes away by itself after a few months to a couple of years. In others, Polymyalgia Rheumatica can be more chronic (long-term) and can linger for much longer.
Similarities to Other Diseases
Polymyalgia Rheumatica is sometimes mistaken for another type of inflammatory arthritis called Rheumatoid Arthritis (RA). Rheumatoid Arthritis can also start in the joints of the shoulders, causing pain and stiffness. Rheumatoid Arthritis isn't like Polymyalgia Rheumatica because in Rheumatoid Arthritis other joints usually become affected over time. Polymyalgia rheumatica should really only affect the joints surrounding the shoulders and the hips.
A variety of other conditions can sometimes act like Polymyalgia Rheumatica, but are not related to any type of arthritis at all. These include some types of cancer, heart infections, and thyroid conditions.
Who Gets Polymyalgia Rheumatica
People who develop Polymyalgia Rheumatica are older than 50. Women are more likely to get Polymyalgia Rheumatica than men.
Polymyalgia Rheumatica can also occur with another condition called Giant Cell Arteritis, which is commonly known as temporal arteritis. About 15 out of every 100 people with Polymyalgia Rheumatica also have temporal arteritis.