"The study's groups were not randomized and researchers did not use a
control group to verify and quantify their findings, a research method that
is considered to be the gold standard."

It is preliminary work and so I doubt it would be prudent to give statins to
smokers for this purpose right now. It certainly warrants further study. Of
course, most smokers who have been smoking enough to have lung damage could
probably use the statins for the usual reasons.

I'll go ahead and point out the obvious that any smoker who is looking for
ways to improve their health other than by stopping smoking is just kidding
themselves. Nothing else could come close.