This plugin adds a new widget which can show statistics for your blog’s/forum’s 
Disqus comments: most popular discussions, top commenters, recent comments.
Configurable are: 
 * Color Theme 
 * Number of items to show 
 * Default tab view (most popular discussions, top commenters, recent comments) 
 * Whether to show the standard WordPress widget title bar 
 * Title of the widget in the title bar

Disqus Widget

Allows the user to display statistics for their blog's/forum's Disqus comments.

pipdig

This plugin will remove any of the default WordPress comments features from your site, and replace this with Disqus.
Please note: Disqus comments will not be automatically imported into your WordPress dashboard. Instead, you can continue to moderate your comments via your Disqus moderation page. This plugin will add a quick link to your Disqus moderation page in the WordPress Admin Bar.
Reasons to use this plugin:
<ul>
<li>Simplify your WordPress dashboard by removing the “Comments” admin menu.</li>
<li>Easy setup: simply add the Disqus shortname in the settings and you’re all set.</li>
<li>Comments are NOT imported to WordPress – save server resources and database size.</li>
<li>Improved spam protection to keep junk out your site’s database.</li>
<li>It has a silly name.</li>
</ul>
This free plugin is brought to you by <a href="https://www.pipdig.co/" rel="nofollow ugc">pipdig</a>

pipDisqus – Lightweight Disqus Comments

A lightweight solution for adding Disqus to your WordPress blog.

Disqus Widget vs pipDisqus – Lightweight Disqus Comments