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PubMed This is a summary of 27 peer-reviewed journal articles Updated
Rheumatology

Understanding Giant Cell Arteritis (GCA)

At a Glance

Giant Cell Arteritis (GCA) is a medical emergency causing inflammation in the arteries of the head. It primarily affects adults over 50 and can lead to permanent vision loss if untreated. Immediate treatment with steroids is highly effective at preventing blindness.

Giant cell arteritis (GCA) is a serious condition where the walls of your medium and large-sized arteries become inflamed [1][2]. While it can affect various parts of the body, it most commonly impacts the arteries in the head, especially those around the temples [3]. Because this inflammation can rapidly block blood flow to vital organs like the eyes and brain, GCA is always treated as a medical emergency [4][5]. While the diagnosis can be frightening, the good news is that steroid treatments work very quickly and are highly effective at preventing vision loss once started [6].

How the Disease Works

GCA is caused by a mistaken immune response where your body’s defense system attacks the lining of your own blood vessels [7][1].

  • Immune Malfunction: Specialized immune cells become overactive and recruit other inflammatory cells to the artery walls [7][1].
  • Vessel Narrowing: As the artery wall thickens from this inflammation, the internal channel narrows [1][2]. This restricts the amount of oxygen-rich blood that can reach your tissues [7][8].
  • Giant Cells: In many cases, immune cells fuse together to form large cells, which gives the disease its name [9].

Who is Most at Risk?

GCA is defined by specific demographic patterns, though it is important to remember that it can affect individuals of any race or ethnicity:

  • Age: It is almost exclusively a disease of older adults. It is rarely seen in people under age 50, and the risk peaks for those in their 70s [10][11][12].
  • Ancestry: People of Northern European or Caucasian descent have the highest rates of GCA [13][14]. It is significantly less common in individuals of Asian, Middle Eastern, or Pacific Islander descent [13][11].
  • Sex: Women are affected two to three times more often than men [15][16].
  • Family History: Having a close relative with GCA may increase your personal risk [17].

The Connection to Polymyalgia Rheumatica (PMR)

GCA is closely linked to Polymyalgia Rheumatica (PMR), a condition characterized by intense stiffness and aching in the shoulders, neck, and hips [18][15]. Doctors often view them as two sides of the same disease spectrum [18][19].

  • Many people with GCA also have symptoms of PMR [20][21].
  • Up to one-third of people who appear to only have PMR may actually have “hidden” inflammation in their large blood vessels [22][23].

Why This is a Medical Emergency

The most serious complication of GCA is sudden, permanent vision loss [4][5]. This happens when the inflammation shuts off the blood supply to the optic nerve, a condition called Arteritic Anterior Ischemic Optic Neuropathy (AAION) [24][4].

Because the inflammation can cause a complete blockage or a blood clot at any time, any new visual symptom—such as double vision or temporary blurring—must be evaluated immediately [24][4][25]. While much rarer, GCA can also lead to a stroke if the arteries supplying the brain become blocked [3][26]. Early treatment with high-dose steroids is essential to protect your sight and prevent these serious long-term complications [4][27].

Common questions in this guide

Why is Giant Cell Arteritis considered a medical emergency?
GCA can cause sudden, permanent vision loss by shutting off the blood supply to the optic nerve. Any new visual symptoms or severe headaches require immediate evaluation to prevent irreversible damage.
What is the connection between GCA and Polymyalgia Rheumatica?
GCA and PMR are closely linked and often considered two sides of the same disease spectrum. Many people with GCA also experience PMR symptoms, which include intense stiffness and aching in the shoulders, neck, and hips.
Who is most at risk for developing Giant Cell Arteritis?
GCA primarily affects adults over the age of 50, with the highest risk for those in their 70s. Women are two to three times more likely to develop the condition than men, and it is most common in individuals of Northern European or Caucasian descent.
What are the early warning signs of GCA?
Common early warning signs include new or unusual headaches around the temples, jaw pain when eating or talking, and brief periods of blurred or double vision. You may also feel significant stiffness in your shoulders or hips upon waking.
How is Giant Cell Arteritis treated?
GCA is primarily treated with high-dose steroids to quickly reduce inflammation in the blood vessels. This treatment works very rapidly and is highly effective at protecting your eyesight and preventing long-term complications.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Given my symptoms, what is the likelihood that I have Giant Cell Arteritis?
  2. 2.What is my risk for permanent vision loss, and what specific warning signs should I watch for right now?
  3. 3.Since I have symptoms of Polymyalgia Rheumatica, does that change how we monitor for GCA?
  4. 4.If a temporal artery biopsy is needed, how soon can it be performed, and should I start treatment before the procedure?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (27)
  1. 1

    Vasculitogenic T Cells in Large Vessel Vasculitis.

    Watanabe R, Hashimoto M

    Frontiers in immunology 2022; (13()):923582 doi:10.3389/fimmu.2022.923582.

    PMID: 35784327
  2. 2

    Functionally Heterogenous Macrophage Subsets in the Pathogenesis of Giant Cell Arteritis: Novel Targets for Disease Monitoring and Treatment.

    Esen I, Jiemy WF, van Sleen Y, et al.

    Journal of clinical medicine 2021; (10(21)) doi:10.3390/jcm10214958.

    PMID: 34768479
  3. 3

    Multimodality imaging to assess diagnosis and evaluate complications of large vesselarteritis.

    Aghayev A, Weber B, Lins de Carvalho T, et al.

    Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 2024; (37()):101864 doi:10.1016/j.nuclcard.2024.101864.

    PMID: 38663459
  4. 4

    Unilateral Central Retinal Artery Occlusion Revealing Giant Cell Arteritis: A Case Report.

    Lazaar H, Moumni A, Aziz A, et al.

    Cureus 2025; (17(3)):e80452 doi:10.7759/cureus.80452.

    PMID: 40225509
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    Bilateral Giant Cell Arteritis Presenting as Bilateral Sudden Vision Loss.

    Modi DK, Sheth K, Wade S, et al.

    Connecticut medicine 2017; (81(4)):235-236.

    PMID: 29714410
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    Polymyalgia Rheumatica and Giant Cell Arteritis: Rapid Evidence Review.

    Raleigh MF, Stoddard J, Darrow HJ

    American family physician 2022; (106(4)):420-426.

    PMID: 36260899
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    [Epidemiology and pathophysiology of giant cell arteritis].

    Greigert H, Bonnotte B, Samson M

    La Revue du praticien 2023; (73(4)):380-386.

    PMID: 37289150
  8. 8

    [Large Vessel Vasculitides: Giant Cell Arteritis and Takayasu Arteritis - Similarities and Differences].

    Gloor AD, Christ L

    Therapeutische Umschau. Revue therapeutique 2022; (79(5)):221-228 doi:10.1024/0040-5930/a001353.

    PMID: 35583023
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    [Pathogenesis of large vessel vasculitis].

    Samson M, Bonnotte B

    La Revue de medecine interne 2016; (37(4)):264-73.

    PMID: 26620872
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    Epidemiology of giant cell arteritis in Waikato, Aotearoa New Zealand.

    van Dantzig P, Quincey V, Kurz J, et al.

    The New Zealand medical journal 2024; (137(1592)):14-21 doi:10.26635/6965.6379.

    PMID: 38513200
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    Clinical Decision-Making Case: A Giant Headache.

    Portman M, Herman L

    Journal of education & teaching in emergency medicine 2025; (10(5)):CE239-CE259 doi:10.21980/J8.52322.

    PMID: 41522642
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    Clinical Diagnosis of Temporal Arteritis With Seronegative and Negative Biopsy Studies.

    Bayas A, Carranza O, Swerdloff MA

    Cureus 2022; (14(11)):e31011 doi:10.7759/cureus.31011.

    PMID: 36475126
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    Incidence and prevalence of giant cell arteritis and polymyalgia rheumatica: A systematic literature review.

    Sharma A, Mohammad AJ, Turesson C

    Seminars in arthritis and rheumatism 2020; (50(5)):1040-1048 doi:10.1016/j.semarthrit.2020.07.005.

    PMID: 32911281
  14. 14

    An interesting case of temporal arteritis that manifested as ptosis and diplopia.

    Martis A, Hassan RS, Alburquerque AG, et al.

    Oxford medical case reports 2020; (2020(11)):omaa099 doi:10.1093/omcr/omaa099.

    PMID: 33269083
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    Giant Cell Arteritis and Polymyalgia Rheumatica: 2016 Update.

    Nesher G, Breuer GS

    Rambam Maimonides medical journal 2016; (7(4)) doi:10.5041/RMMJ.10262.

    PMID: 27824543
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    Management of difficult polymyalgia rheumatica and giant cell arteritis: Updates for clinical practice.

    Lally L, Spiera R

    Best practice & research. Clinical rheumatology 2018; (32(6)):803-812 doi:10.1016/j.berh.2019.04.006.

    PMID: 31427056
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    Familial risks between giant cell arteritis and Takayasu arteritis and other autoimmune diseases in the population of Sweden.

    Thomsen H, Li X, Sundquist K, et al.

    Scientific reports 2020; (10(1)):20887 doi:10.1038/s41598-020-77857-7.

    PMID: 33257751
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    Update on the Treatment of Giant Cell Arteritis and Polymyalgia Rheumatica.

    El Chami S, Springer JM

    The Medical clinics of North America 2021; (105(2)):311-324 doi:10.1016/j.mcna.2020.09.014.

    PMID: 33589105
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    Update on the Treatment of Giant Cell Arteritis and Polymyalgia Rheumatica.

    El Chami S, Springer JM

    Rheumatic diseases clinics of North America 2022; (48(2)):493-506 doi:10.1016/j.rdc.2022.02.007.

    PMID: 35400374
  20. 20

    Development of Giant Cell Arteritis after Treating Polymyalgia or Peripheral Arthritis: A Retrospective Case-control Study.

    Liozon E, de Boysson H, Dalmay F, et al.

    The Journal of rheumatology 2018; (45(5)):678-685 doi:10.3899/jrheum.170455.

    PMID: 29545449
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    Giant Cell Arteritis among Fevers of Unknown Origin (FUO): An Atypical Presentation.

    Grazioli-Gauthier L, Marcoli N, Vanini G, et al.

    European journal of case reports in internal medicine 2021; (8(3)):002254 doi:10.12890/2021_002254.

    PMID: 33768070
  22. 22

    The utility of 18F-FDG-PET/CT in detecting extracranial large vessel vasculitis in rheumatic polymyalgia or giant cell arteritis. A systematic review and meta-analysis.

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    Revista clinica espanola 2024; (224(7)):445-456 doi:10.1016/j.rceng.2024.06.005.

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    [News on the imaging of large vessel vasculitis].

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  24. 24

    Arteritic Anterior Ischemic Optic Neuropathy (AAION) Associated with COVID-19 Infection: A Case Report and Review of the Literature.

    Shahraki K, Najafi A, Ashoori N, et al.

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  25. 25

    Bilateral Optic Perineuritis as Initial Presentation of Giant Cell Arteritis.

    Pappolla A, Silveira F, Norscini J, et al.

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    Arterial-embolic Strokes and Painless Vision Loss Due to Phase II Aortitis and Giant Cell Arteritis: A Case Report.

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    PMID: 32192630

This page provides an educational overview of Giant Cell Arteritis (GCA). Because GCA is a medical emergency, immediately seek professional medical care if you experience vision changes or severe new headaches.

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