Nutritional status in non-cancer older adults experiencing dry mouth -meta-analysis and systematic review

Older adults are at increased risk of nutritional deficiencies due to age-related physiological changes, chronic diseases, medication side effects, socioeconomic factors, and declining oral health. This systematic review examines the association between hyposalivation and nutritional status in non-cancer older adults.

The study protocol was registered in PROSPERO (CRD42025645149). Data were extracted from eligible studies, and quality assessment and bias evaluation were conducted. Using a random effects model, a meta-analysis estimated the pooled prevalence of hyposalivation, xerostomia, and malnutrition.

A comprehensive search of PubMed, CINAHL, Web of Science, and Embase was performed from inception to December 2024.

Longitudinal, cross-sectional, and case-control studies were included. After screening 774 potential studies, 14 (11 cross-sectional, two case-control, and one longitudinal cohort) met the inclusion criteria. Heterogeneity was assessed using Cochran's Q and I² statistics, while publication bias was evaluated with Egger's test and funnel plots.

Thirteen studies reported a significant association between hyposalivation and malnutrition in older adults. All studies highlighted impaired chewing, swallowing difficulties, and reduced taste sensitivity. The pooled prevalence of xerostomia was 38 % (95 % CI: 22-57 %) with substantial heterogeneity (I² = 97 %), while the estimated prevalence of malnutrition was 55 % (95 % CI: 34-74 %). The findings suggested a strong link between hyposalivation and malnutrition in non-cancer older adults. However, variability in study designs underscores the need for standardized diagnostic criteria and longitudinal studies to explore the interplay between salivary function and nutritional health in aging populations.

This review highlights the association between hyposalivation and malnutrition in non-cancer older adults. Dry mouth impairs oral function, leading to poor nutrient intake and an increased risk of malnutrition. Early detection and management of hyposalivation are crucial to prevent nutritional problems. The variability in prevalence suggests a need for standardized diagnostic tools and further research to understand better nutritional health concerns associated with hyposalivation, as well as to improve patients' overall health and quality of life..