People with the chronic inflammatory disease known as ankylosing spondylitis often have back pain and stiffness; however, the symptoms that develop with the condition often vary significantly from person to person. While the condition most often affects the spine, it may also affect the hips, shoulders, and other parts of the body (such as the eyes). In rare instances, ankylosing spondylitis may even affect the heart or lungs. The disease is a form of arthritis that affects an estimated 350,000 people in the United States. The cause or causes of ankylosing spondylitis are not yet known, but risk factors for the condition include having a family history of the disease, being male, and having certain infections (though the disease is not contagious). There is no cure for ankylosing spondylitis, but current treatment strategies (which often involve exercise, medications, and regular monitoring) can help people with the disease manage the condition and lead productive lives.