Job stress factors measured by Brief Job Stress Questionnaire and sickness absence among Japanese workers: A longitudinal study

This study aimed to investigate associations between Brief Job Stress Questionnaire (BJSQ)-measured job stress factors and sickness absence in Japanese workers. Among 551 healthy, employed Japanese men and women (age range: 21-73 years) who underwent mental health examinations at the Osaka Medical Center for Health Science and Promotion between 2006 and 2009, 197 (67 men, 130 women) consented to participate in this study. Their sickness absences until the end of March 2010 were then followed-up via postal mail survey, with 112 participants effectively responding to the question on sickness absence (56.9%). The hazard ratio (HR) and 95% confidence interval (CI) were calculated using the Cox proportional hazards model, adjusting for age, sex, and lifestyle factors. Among the 112 respondents, 12 took sickness absence after their study entry, as found during the mean 2.3 years of follow-up (258.8 person-years). Among all sickness absences, those of eight participants were because of mental illness. Physical demands were positively associated with increased risks of all sickness absence (adjusted HR: 2.78, 95% CI: 1.01-7.64). Physical demands were predictive for all sickness absence, and should be alleviated at workplaces to prevent such absence.