The patient is invariably elderly, with the mean age of 75 years.
Incidence increases with advancing age.
Systemic manifestations may include malaise, weight loss and anorexia, headache in the temporal or occipital region, pulseless and indurated temporal artery, night sweats, tongue necrosis and oral ulceration, dental abscess, scalp pain, scalp necrosis and jaw claudication when eating. Other systemic manifestations include depression, mental disturbance, breast masses, gynecological disorders, persistent flu-like illness, chronic pharyngitis, vertigo, muscle aches, cardiac arrhythmia, congestive heart failure, and myocardial infarction. Further ocular manifestations are tonic pupil, Horner's syndrome, ocular hypotony, chronic uveitis, episcleritis and scleritis, conjunctivitis, ocular ischemic syndrome, visual hallucinations, posterior chiasmal field loss, cortical blindness, and ocular ischemic syndrome. Significant infiltration can lead to vessel occlusion with resultant ischemia and dysfunction of the organ system fed by the vessel. The degree of ischemia tolerated varies by system, and symptoms often appear for a period of months before diagnosis.