Giant Cell Arteritis
What is Giant Cell Arteritis?
Giant cell arteritis (GCA) is a condition in which certain arteries become inflamed. It is also called temporal arteritis, as it often affects the arteries near the temples, although it can involve arteries in just about any part of the body. The inflammation of the involved artery leads to narrowing and sometimes to complete blockage of the blood vessel. This results in the surrounding tissues being deprived of an adequate blood supply.
When GCA involves the arteries that supply blood to the eyes, blindness in one or both eyes may develop suddenly. Strokes may rarely occur. Some of the more common symptoms in GCA include headaches, pain in the jaw or tongue muscles when eating or talking, and tenderness of the scalp over the temples. GCA and PMR seem to be related, as they often occur together. Over 10 percent of people with PMR also have GCA; approximately 50 percent of people with GCA also have PMR.
The causes of PMR and GCA are not known. Because these are disorders that occur primarily in older people, it has been suggested that these diseases may be related somehow to the process of aging. A genetic predisposition seems to be involved.
- PMR and GCA almost always occur in people over the age of 50; the average age of persons with these diseases is approximately 70.
- PMR and GCA occur twice as often in women as in men.
- Whites have a stronger predisposition to PMR and GCA.
- The prevalence of PMR is 700 per 100,000; that of GCA is 200 per 100,000.
PMR is a syndrome, and unfortunately, there are no specific tests. Other conditions that cause symptoms similar to PMR need to be excluded before the diagnosis of PMR can be confidently made. The diagnosis of PMR is made based on the history and physical examination along with blood tests. A biopsy of an affected blood vessel, usually the temporal artery, is necessary to confirm GCA.
The goal in treating PMR and GCA is to relieve the symptoms and, in the case of GCA, to prevent damage to the tissues. The most commonly used medication is prednisone. Usually patients with PMR respond very quickly to low doses; patients with GCA usually require larger doses of this medication. Treatment often extends for two years or longer. In mild cases of PMR, it may be possible to treat the symptoms with non