Shared and independent associations of psychosocial factors on work status among men with subacute low back pain.

OBJECTIVES: Psychosocial variables are acknowledged predictors of back disability, but multivariate studies are needed to understand their independent and overlapping effects. The objective of this prospective cohort study was to evaluate independent and shared associations of psychosocial variables on work status after first onset of low back pain (LBP) in working men.
METHODS: One hundred forty male military personnel reporting subacute, first onset LBP (2 mo average duration) completed an interview-based and survey-based psychosocial assessment within the domains of job satisfaction, stress and coping, pain perceptions and beliefs, perceived functional disability, and mood disturbance. Work status was assessed at baseline, 6 and 12-month postpain onset.
RESULTS: In logistic regression analyses at baseline, work status was associated with pain interference and perceptions of physical impairment. Beyond 2 months, the extent to which pain was believed to interfere with function was the only significant predictor of subsequent changes in work status. Job dissatisfaction was associated with more impaired work status, but not after controlling for income. Depressive and anxious mood symptoms were prevalent but failed to explain additional variance in work status. DISCUSSION: After first onset of men with subacute LBP, self-reported pain intensity and functional limitation account for most of the variance in work status explained by psychosocial factors; however, the resulting disability can be accompanied by mild to moderate mood symptoms. This suggests that interventions to improve function, if commenced early in the course of subacute pain, might prevent work disability.