Giant cell arteritis and polymyalgia rheumatica

Polymyalgia rheumatica is a clinical syndrome characterized by aching and morning stiffness in the proximal extremities, neck, and torso. The symptoms in polymyalgia rheumatica are due, at least in part, to a mild inflammation of the proximal joints, bursae, tenosynovial membranes and ligaments. In some instances more distal involvement may also occur which tends to be mild and relatively transient. Giant cell arteritis and polymyalgia rheumatica are closely related to each other in that they affect the same populations and frequently occur in the same patient. Approximately one half of patients with giant cell arteritis have symptoms of polymyalgia rheumatica whereas in a series of patients with polymyalgia rheumatica as the primary diagnosis, about 15 to 20% have been shown to have giant cell arteritis by temporal artery biopsy or convincing clinical symptoms. Thus, polymyalgia rheumatica is a more common condition than giant cell arteritis. The interrelationships between these two processes are schematically shown. Both conditions appear to have become more common in recent years. It is uncertain whether the increase in frequency is the result of improved recognition of these conditions or whether there has been an actual rise in their incidence.