About polymyositis

About Polymyositis About Polymyositis

What is polymyositis (PM)?

Polymyositis is a rare disorder. In fact, it is believed that only about one in 5,000 people have polymyositis (or dermatomyositis) in the United States today.

Anyone can get polymyositis. But some people are more likely to have it than others. It occurs generally in people who are in their 30s through 50s. Twice as many women have polymyositis as men. Also, it is more common in African Americans than Caucasians. Polymyositis is believed to be an autoimmune disease.

Learn about
DM and PM.

Get the facts about how dermatomyositis and polymyositis can affect your muscles and impact your body.

Watch Video
  

Signs, symptoms, and possible causes

Muscle weakness

The main symptom of polymyositis is muscle weakness. This can include:

  •  A loss of strength in the hips and legs, but no pain—this can make it difficult to walk or climb stairs
  •  Weakness in the shoulders or neck—this can make it harder to lift items or reach things above your head

Polymyositis can cause your muscles to grow weaker over time.

Other signs or symptoms of polymyositis

In addition to muscle weakness, some polymyositis patients experience:

  •  Difficulty swallowing or speaking
  •  Weight loss
  •  Mild joint or muscle pain
  •  Fever
  •  Fatigue

Some patients also have shortness of breath, an irregular heartbeat, or other heart problems.

Many times, polymyositis is idiopathic. That means the cause of the disease is not known. But, there are some theories about the causes of polymyositis, including:

Cancer:

Some types of cancers may be associated with polymyositis

Infection:

A viral infection of the muscles may cause the inflammation that occurs in polymyositis

If you have polymyositis, it's important to talk to your healthcare team about your specific situation.

Stephanie

Living with polymyositis since 2009

“The day I was diagnosed was such a relief. Somebody finally knew what I had and what was going on!”

Watch Video
  

Muscle weakness versus fatigue

It may be easy to confuse muscle weakness with the general feeling of tiredness and weariness caused by fatigue. Both symptoms can occur as a result of polymyositis.

Muscle weakness is a loss of strength. You’ll have difficulty climbing stairs, getting up from a chair, or lifting objects with your arms. Fatigue, on the other hand, is more or less feeling like you simply cannot get out of bed all day.

Both of these symptoms can be troublesome. Each can get in the way of your daily activities and pursuits. And it’s important to tell one apart from the other. If you are treating polymyositis and muscle weakness returns, it can be a sign of a flare-up. If fatigue is a problem, it could be a sign of treatment side effects or your condition.

But how can you tell these two symptoms apart? Your doctor can. And it’s important to inform him or her if you experience any changes in the way you are feeling. Through testing and evaluation, your doctor will work with you to help manage these and your other symptoms. You may need to make some adjustments to your overall polymyositis treatment plan.

More from DM/PM & YOU

Are you a care partner?

Get tips to help you coordinate the care of your loved one.

Test your
knowledge

Myositis and polymyositis are two words for the same thing.

Correct
False—There are more than one disease in the myositis family. Polymyositis is just one type. These conditions include:
  • Dermatomyositis (DM)
  • Polymyositis (PM)
  • Inclusion-body myositis (IBM)
All of these diseases cause chronic muscle inflammation and weakness.
Incorrect
False—There are more than one disease in the myositis family. Polymyositis is just one type. These conditions include:
  • Dermatomyositis (DM)
  • Polymyositis (PM)
  • Inclusion-body myositis (IBM)
All of these diseases cause chronic muscle inflammation and weakness.

Treating polymyositis.

Learn about your treatment options.

Autoimmune disease

Normally, the immune system protects your body from outside invaders. It can detect anything from a virus to a splinter. Then, it attacks the invader. Autoimmune disease causes the immune system to become confused and attack healthy tissue.

X

Viral Infection

Viruses invade living cells to produce multiple copies of the virus. Viral infections include the common cold and flu and cannot be treated with antibiotics.

X