The symptoms of ankylosing spondylitis (AS) usually develop slowly over several months or years. The symptoms may come and go, and improve or get worse, over many years. AS usually first starts to develop between 20 to 30 years of age.

Can ankylosing spondylitis come on suddenly?

Ankylosing spondylitis causes chronic pain that can come and go. You might experience periods of flares and stiffness, and other times when you don't feel pain as acutely. The symptoms may ease up or disappear for a period of time, but they ultimately return.

When does ankylosing spondylitis appear?

Although symptoms usually start to appear in late adolescence or early adulthood (ages 17 to 45), symptoms can occur in children or much later in life. The most common early symptoms of AS are frequent pain and stiffness in the lower back and buttocks, which comes on gradually over the course of a few weeks or months.