How much do you feel that your speech problems are connected to anxiety?

How much do you feel that your speech problems are connected to anxiety? I'm sure just about everybody with a speech problem has anxiety about it, but I'm wondering about anxiety as a cause or aggravator. When I'm hitting the energy drinks too much I notice my general awkwardness and anxiety increases a lot, and the stuttering comes with it. If I don't get enough sleep, caffeine-related or not, it also gets worse. Funny enough tho, my whole life I've actually had LESS speech problems when it comes to speaking in public, interviews, anything high-pressure. The more casual the conversation the worse it gets. So that doesn't exactly back up the anxiety theory. I've also had a theory for a bit that I don't have a speech problem per se anymore. I feel like I have an anxiety problem. When I'm talking, I (think I) can anticipate which words I'm going to stumble on and choose a different word, or use some other trick to get around it. Or, less ideally, I don't redirect in time and I just can't say the word at all. But I never actually let myself TRY to say the word. I have so much anxiety about assuming it's going to be a problem...but what if it's really not? What if the anxiety around the stutter I definitely USED TO have is the real problem?