If you or a loved one has ankylosing spondylitis, learning more about the condition can help you manage symptoms and make informed treatment choices. In this article, you’ll find key facts about how common it is, what causes it, its symptoms, and treatment options.

Having clear information may also make a diagnosis feel less overwhelming. Whether you’re looking for basic facts or specific numbers, the details here can help you feel more confident about navigating the condition.

1. Ankylosing Spondylitis Is Rare

Ankylosing spondylitis is uncommon, though estimates vary. According to MedlinePlus, it affects up to 13 out of every 1,000 people in the United States. Other sources report slightly different numbers.

Genetics also play a role — some groups are more likely to have genes linked to the condition, making it more common in certain areas.

2. Ankylosing Spondylitis Statistics Show It’s More Common in Certain Populations

Some people are more likely to develop ankylosing spondylitis than others. For example, Harvard Health Publishing reports that men are 10 times more likely to be diagnosed with the condition than women. However, some doctors believe this difference may not mean the condition is more common in men than women. Instead, ankylosing spondylitis may appear more severe in men on X-rays, so it’s easier for them to be diagnosed. As imaging tests improve, it will become easier for women to be diagnosed. Recent research suggests that the rates of ankylosing spondylitis in men and women may be closer than once thought.

Most people diagnosed with ankylosing spondylitis are under 40. About 80 percent are diagnosed around age 30.

Having certain health conditions may also increase the risk of developing ankylosing spondylitis. These conditions include psoriasis, ulcerative colitis, and Crohn’s disease — the latter two are types of inflammatory bowel disease.

Race and ethnicity may also play a role in the risk of ankylosing spondylitis. However, this could be due to differences in access to healthcare and diagnostic procedures among racial and ethnic groups. Right now, it’s unclear whether race or ethnicity puts you at an increased risk of developing ankylosing spondylitis.

3. Ankylosing Spondylitis Has Genetic Connections

If a close relative has ankylosing spondylitis, your risk of developing it is higher. This is mostly due to genetic mutations (changes), with the most well-known occurring in the HLA-B27 gene. More than 90 percent of white individuals diagnosed with ankylosing spondylitis have this mutation.

However, genetics alone don’t determine who develops the condition. Many people with the HLA-B27 gene mutation never get ankylosing spondylitis, which suggests that another factor must trigger the disease in people who are more likely to have it.

What Can Trigger Ankylosing Spondylitis?

Ongoing research has identified several environmental factors that may trigger ankylosing spondylitis in people with a genetic risk. Smoking is one potential trigger — it may increase the risk of developing the disease and make treatment less effective. Some studies even suggest that smoking may speed up spinal damage. Other possible triggers include infections, changes in gut bacteria, sleep problems, and pollution.

Members on MySpondylitisTeam mention their triggers. “In my experience, stress is a major trigger for flares,” one said. “For example, for me, I notice an increase in S/I, shoulder and feet joint pain, quality of sleep decline, and mood about two days after I have a glass of wine or a few chocolates,” someone else shared. Yet another said, “Traveling triggers a flare-up for me.”

These factors are based on anecdotal evidence, meaning they come from personal reports rather than large studies. Researchers need to study them further to better understand what triggers ankylosing spondylitis and how it affects the body.

4. Lower Back Pain and Hip Pain Are the Most Common Symptoms of Ankylosing Spondylitis

Pain in the lower back and hips is the most common symptom of ankylosing spondylitis. For some people, this inflammatory back pain may get bad enough that they need mobility devices, like a walker or a wheelchair, to help them move without pain.

Although the lower back and hips are often where pain starts for people living with ankylosing spondylitis, that pain can spread. It can affect the whole spine, as well as other joints in the arms, legs, and torso. Some people may experience neck pain or foot and heel pain. Eventually, inflammation related to ankylosing spondylitis can also affect the lungs and the eyes.

5. Ankylosing Spondylitis Dates Back to Ancient Egypt

If you’re wondering when ankylosing spondylitis was discovered, researchers have found evidence of the condition in Egyptian mummies dating back to 1500 B.C.E.

However, it wasn’t officially identified until 1893, when Russian neurologist Vladimir Bekhterev described it. Two other researchers made similar discoveries in 1897 and 1898, leading to different names being used for the same disease. The connection to the HLA-B27 gene wasn’t discovered until 1984.

6. Ankylosing Spondylitis Can’t Be Cured, But It Can Be Treated

Once diagnosed, ankylosing spondylitis is a lifelong condition. However, various treatments can help you feel better and slow disease progression. These include:

• Focused exercise, often as part of physical therapy or directed by a physical therapist
• Medications, like disease-modifying antirheumatic drugs, biologics, corticosteroids, and nonsteroidal anti-inflammatory drugs (NSAIDs)
• Surgery, like a spinal fusion, though this is rare

In addition, understanding what triggers ankylosing spondylitis in your body and avoiding them can help a lot. As one MySpondylitisTeam member shared, “The task is to identify what it is that triggers your inflammatory response and work to get rid of or get help managing the trigger.”

What Is the Life Expectancy of Someone With Ankylosing Spondylitis?

Although ankylosing spondylitis itself doesn’t shorten life expectancy, the inflammation it causes can lead to other health issues, such as osteoporosis (weakened bones) and cardiovascular (heart) disease. Over time, this may contribute to atherosclerosis, which can increase the risk of heart attack or stroke. Regular checkups with your rheumatologist and appropriate treatment adjustments can help lower these risks and keep the condition under control.

Talk With Others Who Understand

On MySpondylitisTeam, the social network for people with spondylitis and their loved ones, more than 99,000 members come together to ask questions, give advice, and share their stories with others who understand life with spondylitis.

What is something you think people should know about ankylosing spondylitis? Do you know a fact other people may not be aware of? Share your experience in the comments below, or start a conversation by posting on your Activities page.