Factors associated with hyposalivation and xerostomia in older persons in South Brazil

This study aimed to investigate characteristics associated with xerostomia and hyposalivation in older persons.

Saliva is one of the most important body fluids and plays an important role in food bolus formation, lubricating the oral mucosa and protecting teeth against demineralisation.

This is a cross-sectional study nested within a cohort and includes a sample of 872 older persons living independently in the community, both in rural and urban areas in Carlos Barbosa, Brazil. Data collection included standardised interviews to identify sociodemographic, behavioural and health-related variables, as well as oral clinical examination performed by two trained/calibrated dentists. Poisson regressions with robust variance were used to calculate the crude and adjusted prevalence ratios (PR) and their respective 95% confidence intervals.

The mean age was 68.5 ± 6.7 years, and the majority of the sample consisted of women (65.3%). The prevalence of xerostomia, of low stimulated salivary flow rate and low at rest salivary flow rate were 338 (38.8%), 494 (56.6%), 320 (36.7%), respectively. In the final adjusted model, women had a significantly increased prevalence of xerostomia (PR = 1.34; 95% CI: 1.12-1.61), as well as participants taking medication continuously (PR = 1.45; 95% CI: 1.16-1.82) and those with depressive symptoms (PR = 1.49; 95% CI: 1.27-1.76). Lower at rest (PR = 1.45, 95% CI: 1.22-1.72) and lower stimulated salivary flow were more prevalent in women (PR = 1.27, 95% CI: 1.11-1.44), while lower stimulated salivary flow was more prevalent in older persons taking medication continuously (PR = 1.24, 95% CI: 1.07-1.43).

Salivary hypofunction and xerostomia were more prevalent in women and in those with continuous medication use; however, depressive symptoms were associated only with xerostomia. Measures are required to promote oral comfort in cases of xerostomia, thereby reducing the unpleasant sensation of dry mouth and hyposalivation consequences in clinical practice.