Little is known of the natural history of dry mouth among older people, because very little information is available on changes in dry mouth over time among population-based samples. Objectives: To describe changes in dry mouth over a 6-year period among older S outh Australian males and females. Methods: Prospective cohort study of people aged 60+ years at baseline (in 1991/92) who were representative of the populations of Adelaide and Mt Gambier. At the 5-year assessment in 1996/97 and again 6 years later, participants completed the Xerostomia Inventory (XI; Thomson et al, Community Dental Health 16: 12-17, 1999) and a single-item question on dry mouth. Unstimulated salivary flow was measured using the spit method. At baseline, 5 and 11 years, information was collected on medications taken in the previous 2 weeks. Results: Complete data were available for 269 dentate individuals. Between the 5- and 11-year assessments: the prevalence of xerostomia increased from 20.4% to 24.4%; the mean XI score increased from 19.8 (sd, 6.2) to 20.0 (sd, 6.5); and the mean flow rate showed no change. A salivary flow rate of <0.1 ml/min (indicating salivary gland hypofunction, or SGH) was observed among 24.2% at 5 years, but only 9.7% at 11 years. Proportionally more females than males had SGH at both 5 and 11 years (and more became new cases by 11 years). Medication prevalence increased from 58.8% to 95.7% over the assessment period, with those taking more medications having more severe xerostomia. Conclusion: While the prevalence and severity of xerostomia increase over time among older people (particularly females), the pattern with respect to salivary flow is less clear-cut. Supported by NHMRC, NIH DE-09588.

Thomson WM*, Spencer AJ, Chalmers J, Carter KD

Presented at the 45th Annual Meeting of the ANZ Division of the IADR, 25-28 September 2005, Queenstown, New Zealand

Note: * indicates presenter