Sleep Bruxism: Mapping Potential Direct and Indirect Risk Pathways in EPISONO Adult Population‐Based Study

Aim To explore the direct and indirect pathways through which sociodemographic, psychological, behavioural, and clinical factors influence sleep bruxism (SB). Methods This cross‐sectional study was conducted with a sample of 686 adults (mean age of 50.1 years; 380 female and 306 male), from a total of 712 individuals from the Sao Paulo Epidemiological Sleep Study (EPISONO) follow performed in 2015. SB was assessed using self‐report, overnight polysomnography (PSG‐based), and combined methods. Sociodemographic, psychological, behavioural and clinical factors were assessed. Structural Equation Modelling was used to examine the pathways between potential risk factors and SB. Results From an initial sample of 1042, 712 returned for follow‐up and 686 individuals were eligible based on the SB outcomes evaluated and having undergone PSG. The SB self‐reported prevalence was 17.1%, 30.5% presented PSG‐based SB and 7.4% in combination of methods (self‐report+PSG). Sleep bruxism (assessed by all methods) was directly associated with higher levels of insomnia and younger age. Higher socioeconomic status was directly associated with self‐reported SB, whereas PSG‐based and self‐report+PSG SB were associated with increased obstructive sleep apnea and smoking. Regarding indirect effects, elevated anxiety and depressive symptoms indirectly impacted all forms of SB via increased insomnia levels. Conclusions Our findings highlight distinct and overlapping pathways of SB. Insomnia and younger age consistently predicted SB, while psychological factors indirectly impacted SB via insomnia. Demographic, behavioural, and clinical factors showed direct associations that varied according to the assessment method.