Health literacy, oral diseases, and contributing pathways: results from the Lifelines Cohort Study

Objective: Health literacy (HL), the ability to deal with information related to one's health, may affect oral health via several routes. Therefore, this study aimed to examine the association of HL with oral diseases, and whether this association is mediated by oral health behaviour and dental care utilisation.

Methods: We included 26,983 participants from the prospective multigenerational Dutch Lifelines Cohort Study to estimate the association between limited health literacy, and self-reported oral health outcomes (edentulism and gingivitis), and mediation by oral health behaviour and dental care utilisation. Structural equation modelling was used to assess HL's direct, indirect, and total effects on oral health outcomes.

Results: Limited health-literate participants had increased odds of having poor oral health outcomes, i.e. edentulism (odds ratio: 1.41; 95 %-confidence interval: 1.24 to 1.58) and gingivitis (1.22; 1.14 to 1.30). After adjustment for age, income, and education, brushing behaviour and dental care utilization showed a significant mediation effect. Brushing behaviour mediated 7.4 % of the association between HL and edentulism and 6.7 % for gingivitis. Dental visits accounted for 38.0 % of the association between HL and edentulism and 16.4 % for gingivitis.

Conclusions: Limited HL makes edentulism and gingivitis more likely, with poor oral health behaviour and inadequate dental care utilisation being important mediators. The findings suggest that interventions should focus on helping dental professionals recognize patients with limited HL and providing training in patient-centered communication to improve oral health outcomes.

Clinical significance: This study demonstrates that limited health literacy significantly increases the risk of edentulism and gingivitis, mediated by inadequate oral health behaviours and dental care utilization. These findings highlight the need for targeted interventions to improve HL, thereby enhancing oral health outcomes and reducing disparities in clinical dental practice.