Perception of dry mouth in a sample of community-dwelling older adults in Japan

The purpose of this study was to examine the prevalence of perceived dry mouth among a group of independently-living elderly persons in Japan, and to determine its association with general disease, medication, and dental status, as well as its effect on oral function. The study population consisted of participants of the Senior Citizens' College. The subjective sensations of oral dryness on waking and while eating a meal were measured by a questionnaire. The number of usable questionnaires was 1003 or 77.9%. The mean age of the subjects was 66.3 +/- 4.2 years, and 53.0% were male. More than one-third (37.8%) of the subjects reported oral dryness on waking. Only 9.1% of them noticed a subjective feeling of dry mouth during eating. Persons who had at least one of these symptoms made up 41.0%. A multiple stepwise logistic regression analysis indicated the following results: Perception of dry mouth on waking was more frequent among males (p < 0.001), persons who had a low BMI (p < 0.05), and those taking two or more prescribed drugs (p < 0.01). Sensation of dry mouth when eating was more frequent among subjects with a low BMI (p < 0.001) and those who wore a denture in the maxillary arch (p < 0.05). Perception of dry mouth when eating was associated with self-assessed chewing ability (p < 0.01) and dissatisfaction with speaking clearly (p < 0.05), as well as dental status. However, dissatisfaction with tasting a meal had a significant relationship with the reports of mouth dryness on waking (p < 0.01). Our findings suggest that a substantially higher percentage of persons have the perception of dry mouth on waking than when eating, which was associated with medications, being male, and having a low BMI. This perception may influence oral function, especially the reported dissatisfaction with tasting foods.