Association between root caries and depressive symptoms among elders in Carlos Barbosa, RS, Brazil

The aim of this study was to evaluate the association between depressive symptoms and root caries among independent-living older persons. All community-dwelling older adults (not hospitalized and not bedridden) living in Carlos Barbosa, RS, Brazil, were invited to participate, and 785 completed the study protocol (standardized questionnaire assessing socio-demographic information and health behavior, Geriatric Depression Scale [GDS] - brief version, and oral examination [DMFT-Root index, Visible Plaque Index and stimulated salivary flow]). Out of them, 390 participants with at least one natural tooth were included in the present analysis. The outcome of interest was the ratio between the number of decayed roots and the number of roots at risk. The association between independent variables (depression and socioeconomic aspects) and the outcome was assessed using negative binomial regression models. Results: The final, fully adjusted model revealed that age (β=0.03, p=0.001), female sex (β=-0.23, p=0.08), living in a rural area (β=0.25, p=0.008), tooth brushing frequency (β=0.43, p=0.025) and stimulated salivary flow (β=-0.012, p<0.0001) were significantly associated with the presence of root caries. In addition, the interaction between male sex and the presence of depression symptoms (β=-0.99, p=0.012) was also independently and significantly associated with root caries. The interaction between male sex and depression symptoms was associated with root caries, suggesting that psychological mechanisms may be involved indirectly in the development of root caries in older adults.