Myositis is a rare disease diagnosed in just 1 in 100,000 people a year.* Some people think the number should be higher as many cases may go unidentified. It is often mistaken for the symptoms of aging even by sufferers or fibromyalgia or depression. Many patient see seven or more doctors before getting the correct diagnosis of Myositis. This is what happened to me.
The three main types of myositis, or inflammatory myopathy, are polymyositis, dermatomyositis, and inclusion body myositis. All 3 diseases involve chronic muscle inflammation, accompanied by muscle weakness.
- There are 2 separate ages of onset: 10 - 15 years and 45 - 60 years.
- Female to male ratio is 2 :1 except in inclusion-body myositis (IBM) where it is reversed.
- Prevalence of the disease is the highest in the Japanese.
* 2013 American College of Rheumatology