Relationship between smoking and olfactory function

Abstract

In recent years, various studies have been conducted on the relationship between smoking and olfactory dysfunction. There are many reports showing that smoking is one of the causes of olfactory dysfunction. In this study, we reviewed the cases of 208 patients whose olfaction was examined with a T&T olfactometer, and we compared smokers (n = 51) and non-smokers (n = 157) in terms of the degree of olfactory dysfunction and the improvement in olfaction. The most common diseases of these patients were post-infectious olfactory dysfunction (32.7%), chronic rhinosinusitis (28.4%), idiopathic olfactory dysfunction (19.2%), and head trauma (11.1%). In this study, there were 24.5% smokers over all, 17.6% for post-infectious olfactory dysfunction, 28.8% for chronic rhinosinusitis, and 30.4% for head trauma. Smokers had significantly severe olfactory dysfunction in all diseases (84.3%; p < 0.05). Moreover, 66.7% of the smokers in post-infectious olfactory dysfunction group significantly showed “no improvement or worsening” (p < 0.05). Our results suggest that olfactory dysfunction can be worsened by smoking. In addition, the smokers in post-infectious group significantly showed not much improvement of olfactory dysfunction. Since smoking affects not only olfactory function but also the human body in various ways, smoking cessation had better to be considered seriously.