I use to have nasal drip at night. I could wake up coughing a good 5-6 times a night because my throat would be itchy. Day one after stopping cigares, it was gone. So yes in my book, it was related to smoking.I had a much harder time getting my nose and sinuses cleared when I quit, than getting my lungs cleared -- muscles in the chest help us get rid of nastiness there, but there's none of that, with sinuses, you just have to wait till they drain. I still wake up stuffy, but it passes much more quickly than it did when I smoked.
Andria