I'd push back on this a bit, OCD is no longer categorized as an anxiety disorder but it's own thing in the DSM-V. Anxiety is a huge component of it to be sure, but a lot of OCD (especially the types of OCD that are centered around taboo thoughts, which is what I mostly have) also spirals around other feelings such as guilt, shame, disgust, or self-hatred. The primary feeling that drives me to do compulsions in response to intrusive thoughts is a mix of all of these, and I don't even know if I would put anxiety at the forefront of it. That being said in the past when I was a kid with OCD I remember anxiety being a larger component of my experience with it, so I know that's a common experience. I have severe OCD but I also have a completely separate anxiety disorder, and these two things are very distinct experiences for me (though I don't doubt that for other people with the two that distinction may not be as clear.)