This article is about house smoking may increase the severity of obstructive sleep apnea (OSA). The authors explain that the correlation between smoking and OSA has not been studied in detail. The results of this study showed that smokers were more likely to have moderate to severe OSA, whereas nonsmokers were more likely to have mild OSA. The severity of OSA was particularly increased in those smokers who smoked at least 1 pack per day for 10 years.
They concluded that the results suggest smoking thikens the lining of the back of the throat, which causes narrowing of the air passages. This then leads to a worsening of the OSA.
So if you are smoker, this study provides yet another reason to give up the habit.