Abstract
Older people living in residential care may have multiple co-morbidities and polypharmacy, which may cause dry mouth and reduce the quality of life. There are a few reports of the relationship between objective, subjective measurement and clinical oral dryness and their effects on oral health-related quality of life among older people. The study's objectives are to investigate the association between salivary gland hypofunction, xerostomia, and oral clinical dryness symptoms in older people living in residential care facilities in Dunedin. The methods included a clinical examination survey and saliva sampling involving 50 older people (80% females) living in residential care in Dunedin. Medications were recorded and analysed. Extra-oral and intraoral examinations were performed using a modified World Health Organisation (WHO) clinical examination protocol. The five-item Summated Xerostomia Inventory-Dutch Version (SXI-D) was used to assess xerostomia in the participants. The unstimulated flow rate was measured. The Challacombe scale was used to measure the clinical manifestations of oral dryness. The results included participants ranging in age from 65 to 99 years (mean age = 83.0; SD 9.1). The prevalence of xerostomia was 34.8%; for salivary gland hypofunction (SGH), it was 26.1%. Only 13.0% had both conditions, and 52.2% had neither. The SXI-D score and salivary flow rate were only weakly and negatively correlated (r=-0.2), but a moderate positive correlation (r = 0.55) between the Challacombe scale and the SXI-D. There was a moderate negative correlation between the Challacombe scale and the flow rate (r = -0.47).As a conclusion, dry mouth is common among older people in residential care, and the relationship between the signs and symptoms of oral dryness is complex and not as clear-cut as may be assumed.