I am now 71 and was only recently diagnosed with AS. Since the onset at age 9 I was diagnosed as Rheumatoid Arthritis. They are both Auto Immune diseases and age is not a determining factor. To determine if you have AS your Rheumatologist will need to do an ex ray of the pelvis, and order two special blood tests (which may not be covered by your insurance) -- but Madicare did in my case. It is important to do this because the two diseases progress in different ways so the medical plan would be different. My major complaints are having to have multiple joint replacements. There are two kinds of AS: one that limits it's activity just to the spine, and the other that can involve most joints and organs, I must have the latter.