Hey Jeff,
We are all a bit different, I do not think their is a 1 case fits all scenario for AS.
Personally my case I believe my case of AS is tied to my intestinal health. I have to have good balance of friendly bacteria.... I avoid starch so as not to have many klebs... and eat a lot of sauerkraut to provide good bacteria.
If you really want to know if your case is tied to your intestinal health have 2-3 colonics performed by certified individual and see how you feel afterwards. When I lived in Arizona... I had them done on a regular basis. I could go from full flare to almost no AS symptoms after each. This was the clincher that my AS is tied to my intestinal health.
Take care,
Tim