Say we are solving a tree decomposition problem, e.g.
given a graph $G = (V, E)$ we try to find a chordal graph $H$ such that $V(H) = V(G)$, $E(G) \in E(H)$ and the maximal clique in $H$ is minimal among all possible $H$.

This problem is known to be NP-hard. For other/better definitions of tree decomposition/treewidth see [Wikipedia][1] 

Is there a way to reduce treewidth to some other NP problems, especially Maximum Independent Set/3-SAT or similar ones?

I found a lot of results of sort "if a graph has a bounded treewidth, then problem XXX has a polynomial solution", but nothing like an algorithm to find treewidth from a solved NP problem instance

  [1]: https://en.wikipedia.org/wiki/Tree_decomposition