Pain-related fear predicts disability, but not pain severity: a path analytic approach of the fear-avoidance model.

Two studies are reported that tested the fear-avoidance (FA) model using path analytic techniques. In study 1, 429 employees with back pain at baseline and back pain at 18 months follow-up completed questionnaires assessing sociodemographic information, pain severity, negative affect, pain-related fear, and disability. Results indicated that pain severity at baseline predicted pain-related fear and disability at follow-up, and that pain-related fear is rather a consequence than an antecedent of pain severity. Results further revealed that the disposition to experience negative affect has a low impact upon pain severity and disability, and is best viewed as a precursor of pain-related fear. Study 2 included 238 employees without back pain at baseline, but who developed back pain at 1 year follow-up. A similar model as in study 1 was tested. Overall, results are in line with those of study 1. Results are discussed in terms of theoretical relevance and clinical implications.

Development of and recovery from short- and long-term low back pain in occupational settings: a prospective cohort study.

Using the data of the EuroBack Unit prospective cohort study, this paper investigated the role of work-related physical factors and psychological variables in predicting the development of and recovery from short-term and long-term LBP. At baseline, 1294 predominantly male industrial workers from 10 companies in Belgium and the Netherlands filled in questionnaires. At follow-up, data from 812 employees were available. Odds ratios (ORs) were calculated using simple and multiple logistic regression analyses. For those workers reporting 0 days LBP in the year prior to baseline, negative affectivity (OR 1.06, 95% CI 1.01-1.11) was a risk factor for the development of short-term LBP (=1-30 days total of LBP in the year prior to follow-up). For those who reported 1-30 days total of LBP in the year prior to baseline, only high fear of (re)injury due to movement (OR 1.07, 95% CI 1.02-1.12) increased the risk for failure to recovery from short-term LBP. For the development of long-term LBP (=more than 30 days total of LBP in the year prior to follow-up), a significant increased risk was observed among workers with high pain severity (OR 1.19, 95% CI 1.01-1.40) and with pain referred to the ankles or feet (OR 2.92, 95% CI 1.09-7.83). The risk was reduced by social support of co-workers (OR 0.73, 95% CI 0.59-0.92) and by manual handling of materials (OR 0.63, 95% CI 0.46-0.85). For those who reported more than 30 days total of LBP in the year prior to baseline, high pain severity (OR 1.18, 95% CI 1.04-1.34) increased the risk for failure to recovery from long-term LBP. Results are compared to the baseline study (Gheldof et al., 2005) and discussed in relation with prospective studies.

Pain and pain-related fear are associated with functional and social disability in an occupational setting: evidence of mediation by pain-related fear.

This study examined the role of work-related, psychosocial and psychological factors in predicting functional and social disability in working employees. In a cross-sectional design, 890 working employees (reporting at least 1 day of back pain during the past year) completed self-report measures of back pain, disability, pain-related fear, negative and positive affectivity, job satisfaction, job stress and physical work load. Regression analyses revealed that pain intensity was a strong predictor of functional (beta = .69, p < .001) and social disability (beta = .67, p < .001). Fear of (re)injury due to movement (beta = .25, p < .001; beta = .28, p < .001) had additional predictive value in both models. Further, (singular) mediation tests indicated that fear for (re)injury partially mediated the relation between pain intensity and disability, and between negative affectivity and disability. Finally, path analyses revealed both fear and pain intensity as mediators between negative affectivity and disability. Overall, our findings point at the relevance of the cognitive-behavioral model of avoidance in occupational settings.

The differential role of pain, work characteristics and pain-related fear in explaining back pain and sick leave in occupational settings.

This cross-sectional questionnaire study investigated the role of pain (pain severity, radiating pain), work characteristics (physical workload, job stressors, job satisfaction), negative affect and pain-related fear in accounting for low back pain (LBP) and sick leave (SL) in 1294 employees from 10 companies in Belgium and the Netherlands. An increased risk for short-term LBP (1-30 days during the last year) was observed for workers reporting high physical workload (OR=2.39), high task exertion (OR=1.63) and high negative affect (OR=1.03). For prolonged LBP (>30 days during the last year) severe pain (OR=13.03), radiating pain (OR=2.37) and fear of work-related activities (OR=3.17) were significant risk factors. A lack of decision latitude decreased the risk of long-term LBP (OR=0.39). Short-term SL (1-30 days during the last year) was associated with severe pain (OR=2.83), high physical workload (OR=2.99) and high fear of movement/(re)injury (OR=1.88). A lack of decision latitude increased the risk of short-term SL (OR=1.92). Long-term SL (>30 days during the last year) was associated with radiating pain (OR=3.80) and high fear of movement/(re)injury (OR=6.35). A lack of co-worker support reduced the risk of long-term SL (OR=0.27). These results suggest that physical load factors are relatively more important in the process leading to short-term LBP and short-term SL, whereas job stressors, severe pain, radiation, and pain-related fear are more important in determining the further course and maintenance of the inability to work. The potential implications of these findings for primary and secondary prevention, and occupational rehabilitation are discussed.