Understanding Giant Cell Arteritis (GCA)
Giant cell arteritis (GCA), sometimes called temporal arteritis, is a serious condition where the lining of your arteries becomes inflamed [1.3.1]. This inflammation causes the arteries to swell and narrow, which reduces blood flow to vital tissues. While any medium-to-large artery can be affected, it most often involves the arteries in the head, especially at the temples [1.3.1, 1.3.4]. The condition gets its name from the abnormally large inflammatory cells, or "giant cells," seen in a biopsy of the affected artery [1.2.1].
Prompt diagnosis and treatment are critical because restricted blood flow can lead to severe complications, including permanent vision loss and stroke [1.6.1]. The cause is not fully known, but it's believed to be an autoimmune response where the body's immune system mistakenly attacks the artery walls [1.3.1].
The Critical Role of Age
Age is the most significant risk factor for developing GCA. The condition almost exclusively affects adults over the age of 50, and the incidence increases with age [1.2.2, 1.2.7].
- Typical Onset: Most people develop signs and symptoms between the ages of 70 and 80 [1.2.2]. The average age of onset is around 72 [1.2.1].
- Rarity in Younger Adults: It is exceptionally rare for anyone under 50 to be diagnosed with GCA [1.2.2].
- Increasing Incidence with Age: Studies have shown that the incidence of GCA rises significantly in individuals over 70 years old [1.2.5].
Key Symptoms and Warning Signs
The onset of GCA can be gradual over several weeks or happen abruptly [1.3.6]. The most common symptom is a new, severe, and persistent headache, often located in the temple area [1.3.1].
Common Cranial Symptoms:
- Headache: A new, throbbing headache, usually on one or both sides of the head near the temples [1.3.4].
- Scalp Tenderness: Pain when touching the scalp, combing hair, or resting your head on a pillow [1.3.1].
- Jaw Claudication: Pain in the jaw muscles that occurs while chewing, which is a very specific sign of GCA [1.3.1].
- Vision Problems: This is the most serious complication. Symptoms can include blurred vision, double vision (diplopia), or a sudden, painless loss of vision in one eye [1.3.1, 1.3.2]. Any vision change is a medical emergency.
Systemic and Other Symptoms:
- Flu-like symptoms, including low-grade fever, fatigue, and a general feeling of being unwell [1.3.4].
- Unintended weight loss and loss of appetite [1.3.1].
- Pain and stiffness in the neck, shoulders, and hips, which are symptoms of polymyalgia rheumatica (PMR) [1.3.1].
The Link Between GCA and Polymyalgia Rheumatica (PMR)
GCA and PMR are closely related inflammatory disorders that often occur together [1.5.5].
- About 40-60% of people with GCA also have symptoms of PMR [1.5.4].
- Conversely, about 16-21% of people with PMR may develop GCA [1.5.4].
PMR causes muscle pain and stiffness, particularly in the shoulders, neck, and hip area, which is typically worse in the morning [1.5.5]. The presence of PMR is a significant risk factor for developing GCA [1.2.2].
| Feature | Giant Cell Arteritis (GCA) | Polymyalgia Rheumatica (PMR) |
|---|---|---|
| Primary Site | Arteries, especially in the head/temples [1.3.1] | Muscles and joints of the neck, shoulders, hips [1.5.3] |
| Key Symptoms | New headache, jaw pain, vision loss [1.3.1] | Severe stiffness and pain in proximal muscles [1.5.3] |
| Major Risk | Permanent blindness, stroke, aortic aneurysm [1.6.1] | Significant disability from pain and stiffness if untreated [1.5.3] |
| Co-occurrence | 40-60% of GCA patients also have PMR [1.5.4] | 16-21% of PMR patients develop GCA [1.5.4] |
Diagnosis and Treatment
If GCA is suspected, a doctor will likely perform a physical exam, order blood tests, and schedule a biopsy of the temporal artery [1.2.1].
- Blood Tests: Doctors look for high levels of inflammatory markers, specifically the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) [1.3.2].
- Temporal Artery Biopsy: This is the definitive test. A small piece of the artery from the temple is removed and examined under a microscope for signs of inflammation and giant cells [1.3.2].
- Imaging: Ultrasound or other imaging tests can sometimes show inflammation in the arteries [1.3.3].
Treatment must begin immediately to prevent vision loss, even before a biopsy confirms the diagnosis [1.4.4].
- Corticosteroids: The primary treatment is a high dose of corticosteroids, like prednisone [1.4.3]. This medication reduces inflammation, and symptoms often improve within 1-3 days [1.4.1]. The dose is gradually tapered over one to two years, or sometimes longer [1.4.4].
- Other Medications: To reduce the side effects of long-term steroid use, doctors may prescribe other drugs. Tocilizumab (Actemra®) is an FDA-approved biologic medication that can help patients reduce their steroid dosage [1.4.3]. Low-dose aspirin may also be recommended to reduce the risk of stroke [1.4.5].
Who is Most at Risk?
Besides age, several other factors increase the risk of developing GCA:
- Sex: Women are about two to three times more likely to develop GCA than men [1.2.2].
- Race and Geographic Region: It is most common in white individuals of Northern European or Scandinavian descent [1.2.2].
- Family History: The condition can sometimes run in families, suggesting a genetic link [1.2.2].
Conclusion
The answer to "what age do you get giant cell arteritis?" is clear: it is a disease of older adulthood, almost never seen in those under 50 and most common in people in their 70s and 80s [1.2.7]. Recognizing the distinct symptoms like a new-onset headache, jaw pain, and vision changes is crucial for this age group. Early and aggressive treatment with corticosteroids is the best way to prevent devastating complications like blindness and lead to a good long-term prognosis. For more information, consult authoritative sources such as the American College of Rheumatology.
