function new_group_is_admin_loop( $user_id = 0 ) {
global $bp, $groups_template;
if ( empty( $user_id ) )
$user_id = $bp->loggedin_user->id;
$groups_template = BP_Groups_Member::get_is_admin_of( $user_id );
}
…or something similar? Untested so your mileage may vary.
Chances are this won’t work, thinking back on it now. But, give it a shot. At the very least that function will return back the groups that the user is the admin of; you may need to do your own custom loop functions afterwards.