How to remove your Disqus account
Use the link named above. All your *personal* information will be removed, as stated on their site. You can also remove associated accounts (such as facebook etc.). See https://docs.disqus.com/help/73/
Direct removal link: https://disqus.com/embed/account/?thread_url=&to_redirect=http%3A%2F%2Fdisqus.com%2Fdashboard%2F%23edit-profile
Helpful Trick: Removing online data
Publicly visible text/images often aren’t properly removed even when you succeed in removing an account. Try editing or removing them manually before removing the account itself. If you’re unsure what happens to your tracks: this can be found mostly in the Terms of Service/Privacy Policy; otherwise you can always contact Disqus and ask personally. By the way, removal requests don’t necessarily mean your data will actually be removed (e.g. due to legal obligations).
Helpful Trick: Remove third-party logins
If you signed up for Disqus using a third-party login such as Facebook or Twitter, you probably want to revoke all access from Disqus. Click here to find out how.