Measuring Dry Mouth in Older People in Residential Care

To investigate and describe the concordance between salivary flow rates and xerostomia among older dependent adults, describe the association between medication use and dry mouth, and describe the impact of dry mouth on oral health-related quality of life (OHRQoL).

A clinical examination survey was conducted with 50 older adults residing in residential care facilities in Dunedin, New Zealand. Xerostomia was measured using the five-item Summated Xerostomia Inventory-Dutch Version (SXI-D), and the unstimulated salivary flow rate was also measured. The clinical manifestations of oral dryness were evaluated using the Clinical Oral Dryness Scoring (CODS) scale. Medications were recorded.

Participants ranged in age from 65 to 99 years (mean 83.0, SD 9.1). The prevalence of xerostomia was 34.8%, while salivary gland hypofunction (SGH) was present in 26.1%. Only 13.0% of participants had both conditions, and 52.2% had neither. A weak negative correlation was observed between the SXI-D score and salivary flow rate (r = -0.20), while a moderate positive correlation was found between the SXI-D and the CODS scale (r = 0.55). Additionally, the CODS scale showed a moderate negative correlation with the salivary flow rate (r = -0.47).

Dry mouth is common among older adults in residential care, but the relationship between its signs and symptoms is complex. Salivary hypofunction data alone do not fully capture the experience of oral dryness, emphasising the need for a more comprehensive approach to diagnosis and treatment.