Last updated on:August 13th, 2021
The key feature of giant cell arteritis (GCA) is a headache that is of new onset. This is classically temporal in location, associated with temporal tenderness, and either unilateral or bilateral. In practice, the description of the headache varies widely; therefore, a high index of suspicion is essential in patients over 50 years of age. The headache of GCA is due to the inflammation following from the underlying vasculitic process.
Scalp tenderness is a common complaint. Patients should be specifically asked if combing or brushing their hair leads to scalp pain. This is thought to be due to the relative ischemia.
Jaw claudication occurs with chewing and can be severe. Patients often require direct questioning for this symptom. This too is thought to be due to relative ischemia.
Systemic symptoms such as fever, fatigue, and weight loss are common. This is believed to be due to the inflammatory cascade.
Visual disturbances such as blurring of vision, diplopia, and loss of vision can occur. This is a serious complication; irreversible blindness may result without prompt treatment. Potential causes of vision loss include anterior ischemic optic neuropathy, central retinal artery occlusion, posterior ischemic optic neuropathy, or posterior circulation ischemic stroke. Of these, anterior ischemic optic neuropathy is the most common, accounting for over 80% of cases.
Symptoms of polymyalgia rheumatica
Roughly half of patients with GCA have polymyalgia rheumatica (PMR); conversely, 15% of patients with PMR have GCA. PMR development may precede GCA; and a new headache in a patient with PMR should always raise concern for GCA. Symptoms of PMR include shoulder or hip girdle pain with prominent morning stiffness. Inflammatory back pain can also occur.
The cause of this overlap is unknown, but it is believe that GCA and PMR may have a shared pathophysiology; and that they may be different manifestations of the same disease process.
Aortitis, aortic dissection, and aortic aneurysms are uncommon complications, but can be devastating if missed.
Symptoms of stroke
Stroke is an uncommon complication. This is due to involvement of the large vessels supplying the brain. The vertebrobasilar territory is most often affected.
Arm claudication is seen in 3-5% of patients. This is due to involvement of the branches of the aortic arch—particularly the subclavian artery.
Demographics and age
GCA occurs in persons >50 years of age; and is more common in patients over 70 years of age. GCA is also more common in women. In the northern hemisphere, the incidence increases with latitude. There is a particularly high incidence in Northern American and Scandinavian populations. The cause for this is unclear.