What is the most efficient approach to fetch category tree, products, brands, counts by subcategory in Symfony + Doctrine

Question

Symfony 1.4 + Doctrine 1.2.

What is the best way to minimize the number of queries to retrieve products, subcategories of current category, product counts by subcategory and brand for the result set of the query below? Categories are a nested set.

Here is my query:

    $q = Doctrine_Query::create()
    ->select('c.*, p.product,p.price, b.brand')
    ->from('Category c')
    ->leftJoin('c.Product p')
    ->leftJoin('p.Brand b')
    ->where ('c.root_id = ?', $this->category->getRootId())
    ->andWhere('c.lft >= ?', $this->category->getLft())
    ->andWhere('c.rgt <= ?', $this->category->getRgt())
    ->setHydrationMode(Doctrine_Core::HYDRATE_ARRAY);

   $treeObject = Doctrine::getTable('Category')->getTree();
    $treeObject->setBaseQuery($q);
    $this->treeObject = $treeObject;
    $treeObject->resetBaseQuery();

    $this->products = $q->execute();