My guess? The stress of mood swings. If you're up and down and everything in between without any real warning signs (that you're aware of) of course that is going to make you anxious or something else depending on your personality, experiences, awareness etc. You're going to want to control it and your mind doesn't really know how so, it blerps out things like these comorbid disorders.

When your mood swings are under control how is the rest of your health?