Giant cell arteritis (GCA) affects roughly 10 out of every 100,000 people over age 50 each year, making it the most common form of vasculitis in older adults. At any given time, about 52 per 100,000 people over 50 are living with the condition. Those numbers translate to a significant global burden: by 2050, an estimated 3 million people worldwide will have GCA, with approximately 500,000 experiencing some degree of vision impairment as a result.
Who Gets GCA Most Often
GCA is overwhelmingly a disease of older adults. It virtually never occurs before age 50, and the rates climb steeply from there. Prevalence rises sharply between the 50-to-54 age bracket and the 90-plus group in both men and women. A 2015 population-based estimate found that the overall prevalence among people 50 and older was 204 per 100,000, but the distribution between sexes is far from equal.
Women develop GCA roughly three times as often as men. The prevalence among women 50 and older is about 304 per 100,000 compared to 91 per 100,000 in men. Over a lifetime, a woman’s risk of developing GCA is approximately 1%, while a man’s is about 0.5%. That means roughly 1 in 100 women and 1 in 200 men will be diagnosed at some point.
Geography and Ethnicity Matter
GCA is most common in populations of northern European ancestry, particularly those with Scandinavian roots. Southern Sweden, for example, has some of the highest prevalence estimates documented anywhere. Rates in southern European and Asian populations are consistently lower. The condition has been reported in all ethnic and racial groups globally, but the gap between northern European populations and others is notable enough that researchers have studied whether changing immigration patterns in Scandinavian countries might be shifting regional incidence figures. In Sweden’s Skåne region, the percentage of foreign-born residents over 50 grew from about 12% in 2000 to nearly 20% by 2019, with more recent immigrants arriving from countries where GCA is less common.
The Link to Polymyalgia Rheumatica
About half of all people diagnosed with GCA also have symptoms of polymyalgia rheumatica (PMR), a related inflammatory condition that causes aching and stiffness in the shoulders, neck, and hips. The two conditions share a lot of common ground: both become more common with age, affect women more than men, and follow similar geographic patterns. PMR is far more common on its own, but when someone with PMR develops new headaches, jaw pain, or vision changes, GCA becomes a serious concern.
Vision Loss Risk
The most feared complication of GCA is permanent vision loss, and it’s not rare. In one study of 258 GCA patients, about 22% suffered permanent vision loss. More than half of those cases occurred before steroid treatment had even started, underscoring how quickly the disease can damage the blood supply to the eyes. Even after treatment began, about 23% of patients who had already lost some vision continued to worsen. Only a small fraction, around 5%, saw meaningful improvement after starting steroids.
The timing is striking: vision loss typically clusters around the point of diagnosis, with a median of just 3 days before treatment begins. This narrow window is why GCA is treated as a medical emergency. Once blood flow to the optic nerve is interrupted, the damage is usually irreversible.
How GCA Is Diagnosed
Diagnosis relies on a combination of symptoms, blood tests, imaging, and sometimes a biopsy of the temporal artery. The 2022 classification criteria developed by the American College of Rheumatology and EULAR use a scoring system that weighs different findings. A positive temporal artery biopsy or a characteristic “halo sign” on ultrasound of the temporal artery carries the most weight. Elevated inflammatory markers in the blood, sudden vision loss, new headaches near the temples, scalp tenderness, and jaw pain while chewing all contribute to the score. A person needs to be 50 or older and reach a threshold score of 6 or more points to be classified as having GCA under these criteria.
Impact on Survival
GCA does appear to affect life expectancy, at least in the years following diagnosis. One study comparing 44 GCA patients with 4,400 age- and gender-matched controls found that median survival was 3.7 years after diagnosis for GCA patients, compared with 8.3 years for the control group. Five-year survival was 35% in the GCA group versus 67% in controls. The gap narrowed over time and largely disappeared by about 11 years after diagnosis, suggesting that the highest risk period is the first several years. This likely reflects a combination of the disease itself, complications like stroke or vision loss, and side effects from long-term steroid use.
A Growing Problem
Because GCA is so strongly tied to aging, the global burden is expected to grow substantially as populations get older. The projected 3 million cases worldwide by 2050 represents a significant increase from current numbers. This growth will be especially pronounced in countries with rapidly aging demographics, putting more pressure on healthcare systems to recognize and treat the condition quickly enough to prevent irreversible complications like blindness.