Association Between Oral Health-Related Quality of Life and Depressive Symptoms in Older Adults in Canton Zurich: A Cross-Sectional Pilot Study.

Objectives: The objectives of this study were to assess the association between oral health-related quality of life (OHRQoL) and depressive symptoms among older adults in Canton Zurich, Switzerland, and to explore domain-specific variations. Methods: This pilot cross-sectional study included aging adults aged ≥65 years recruited from a university-based geriatric dental clinic in Zurich between 1 January and 31 March 2025. Participants completed paper-based questionnaires to assess their systemic and oral health, their quality of life (OHIP-14), and depressive symptoms (PHQ-8). Associations were assessed using Spearman's rank correlation (ρ) with 95% confidence intervals estimated via bootstrap resampling. Domain-level analyses were conducted to explore the structure of the association, and a multivariable linear regression was used to assess whether the association persisted after adjustment. Results: A total of 108 participants were included (mean age of 76.2 ± 7.2 years; 53.4% male). Overall levels of OHRQoL and depressive symptoms were low. Higher OHIP-14 scores were moderately associated with higher PHQ-8 scores (ρ = 0.50; p-value < 0.01; 95% CI: 0.34-0.65). This association was consistent across PHQ-8 severity categories and remained significant after adjustment (β = 0.14; 95% CI: 0.06-0.22; p < 0.001). Domain-level analyses indicated stronger association in psychosocial and pain-related domains than for functional limitation. Conclusions: The study demonstrates that poorer OHRQoL was moderately associated with higher depressive symptoms, independently of the covariates examined, particularly in psychosocial domains. These findings suggest that OHRQoL reflects broader experiential and psychological dimensions of health beyond oral function alone, highlighting its relevance for oral health assessment in older adults. As the findings are based on a convenience sample of clinic attendees, larger population-based longitudinal studies are needed to clarify these relationships further.