Validation of an adaptation of the stress process model for predicting low back pain related long-term disability outcomes: a cohort study.

STUDY DESIGN

Twelve-month cohort study.

OBJECTIVE

The aim of the study was to examine the ability of an adaptation of the stress process model to predict different outcomes among low back pain (LBP) sufferers.

SUMMARY OF BACKGROUND DATA

Recently, the stress process model was adapted and was shown to be useful to partially explain long-term disability related to low back pain, an important occupational health problem.

METHODS

French-speaking compensated workers on sick leave because of subacute common LBP (N=439) completed a questionnaire including the adapted stress process model's factors: life events and appraisal, cognitive appraisal of LBP, emotional distress, avoidance coping strategies, and functional disability. Six and 12 months later, participants gave information about their work status, number of days of absence, and functional disability. Regression analyses were performed to identify significant predictive factors of these outcomes. Pain intensity, fear of work, gender, and presence of pain radiating below the knee were used as control variables.

RESULTS

Number of days of absence, functional disability, and absence from work were predicted at 6 and 12 months by cognitive appraisal of LBP and emotional distress. Functional disability was predicted in addition by functional disability at study entry (T1). When the control variables were considered, number of days of absence was predicted at 6 months by cognitive appraisal, fear of work, and being a male, and, in addition, by emotional distress at 12 months. Functional disability was predicted by functional disability t1, emotional distress, cognitive appraisal of LBP, and fear of work at 6 months, and by the same factors and variables at 12 months, except for functional disability t1. Regarding absence from work, it was predicted at 6 months by fear of work and being a male, and at 12 months by cognitive appraisal of LBP and fear of work.

CONCLUSION

In association with fear of work, 2 factors from the adapted stress process model are significantly useful for predicting LBP related long-term disability outcomes and could be targeted by preventive interventions.