The purpose of this survey was to study the sensation of oral dryness and its underlying factors in the 55-year-old population of Oulu (a medium-sized Finnish town), 780 of whom (77%) participated.
In addition to the examination of oral health status and salivary flow rate measurements, depressive symptoms were determined on the basis of the Zung Self-Rating Depression Scale (ZSDS). The participants were also interviewed about their health, medication, physical health, physical activity, smoking habits, alcohol consumption, and factors related to their work.
The prevalence of subjective sensations of dry mouth was 25.8% among men and 33.3% among women (p = 0.025). A statistically significant association was found between a subjective sensation of dry mouth and a low unstimulated flow rate, regular smoking, xerogenic medication, and the presence of at least one illness connected with dry mouth. Those who had a sensation of dry mouth also thought their physical condition and their health to be poorer and more often had a high rate of depressive symptoms. After the confounding factors had been added stepwise into the logistic regression model, depressive symptoms were still significantly associated with the sensation of oral dryness.
When evaluating the causes of the sensation of dry mouth, the possibility of depression as an underlying factor should be considered.