It's certainly possible that exists, but I'm not aware of it if it does. I just wouldn't be surprised if that type of study doesn't exist, is all I'm saying. A quick search on my end found a research article called *SOCIAL ANXIETY DISORDER IN ADULTS WHO STUTTER* -Elaine Blumgart et. al. It's behind a paywall for me, I can only access it through my school. But the conclusion is that people who stutter have higher rates of social anxiety and social phobia, which makes sense. I saw several other papers that had similar conclusions, but nothing on specific diseases associated with such things.