The Relationship Between Fear-avoidance Beliefs in Employees with Chronic Musculoskeletal Pain and Work Productivity: A Longitudinal Study.

This study aimed to identify risk factors for chronic musculoskeletal pain (CMSP) and sought to examine the effect of fear-avoidance beliefs (FABs) on work productivity in workers with CMSP. We performed a longitudinal study using self-administered questionnaires given to employees in three different industries between April 2016 and March 2017. The questionnaire concerned background characteristics, work-related factors and musculoskeletal pain, the Work Functioning Impairment Scale (WFun), and the Japanese version of the Tampa Scale for Kinesiophobia (TSK-J). We performed logistic regression analysis to evaluate factors affecting CMSP and a multi-way analysis of variance to analyze the relationship between FABs and CMSP and the effect of FABs on the ability to function at work. Age (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.00-1.03), mean working hours (OR = 1.18, 95% CI: 1.04-1.33), and changes in working hours (OR = 1.18, 95% CI: 1.02-1.37) were significantly associated with CMSP. Regarding FABs, we found that the stronger the FAB, the greater the WFun score, and that an increase in FABs resulted in a significant increase in WFun scores. This study demonstrated that long or increased working hours may be risk factors for CMSP, and that stronger FABs in those with CMSP are associated with decreased ability to function at work. In addition, measures to reduce FABs in workers with CMSP may be effective.