[@fel64 Member 19 years, 1 month ago]

$topic->topic_last_poster is the ID of the last poster to the topic. user_profile_link( $user_id ) echoes the url of the user’s profile. You’d do something like this I think:

<a href="<?php user_profile_link( $topic->topic_last_poster ); ?>"><?php echo $topic->topic_last_poster_name; ?></a>