Objective: Psychosocial job stress has been associated with sleep disturbances, but its association with sleep bruxism (SB), the stereotype movement disorder related to sleep, is not well understood. The aim of this epidemiological study was to examine the relationship between psychosocial job stress and SB.
Methods: 1944 male and 736 female factory workers participated in this study (response rate 78.1%). Perceived job stress was evaluated with the Japanese version of the generic job stress questionnaire, which covered 13 job stress variables. SB was assessed by the question, 'Do you grind or clench your teeth during your sleep or has anyone in your family told you that you grind your teeth during your sleep?' Response options were 'never', 'seldom', 'sometimes' or 'often'. SB was considered present if the answer was 'sometimes' or 'often'.
Results: Overall, 30.9% of males and 20.2% of females reported SB. In males, workers with low social support from supervisors [odds ratio (OR) = 1.34, 95% confidence interval (CI) 1.08-1.68] or from colleagues (OR 1.47, 95% CI 1.17-1.83), and high depressive symptoms (OR 1.60, 95% CI 1.26-2.03) had a significantly increased risk of SB after controlling for confounders. By contrast, no significant association was found in females.
Conclusions: We conclude that SB is weakly associated with some aspects of job stress in men but not in women among the Japanese working population.