To what extent do current and past physical and psychosocial occupational factors explain care-seeking for low back pain in a working population? Results from the Musculoskeletal Intervention Center-Norrtälje Study.

STUDY DESIGN A population-based case referent study. OBJECTIVES To determine whether current and past physical and psychosocial occupational factors are associated with care-seeking for low back pain in working men and women. SUMMARY OF BACKGROUND DATA The importance of physical and psychosocial workloads as causal factors of low back pain has mostly been investigated in special occupational groups and with a cross-sectional design, which makes generalizability and interpretations more difficult. METHODS The study comprised 2118 working men and women 20 to 59 years old (695 cases, and 1423 referents). Cases were defined as persons seeking care by any caregiver for low back pain. The exposure assessments were made through questionnaires and interviews about current and past physical and psychosocial loads during work and leisure time. RESULTS In a logistic regression analysis, physical load from forward bending in men (RR = 1.8) and high physical load, in general, in women (RR = 2.0) showed increased relative risks. Psychosocial factors alone seemed to be of less importance in women, but "poor job satisfaction" and "mostly routine work without possibilities of learning" increased the risk in men. Combined current and past exposures further increased the risks. A combination of high physical and psychosocial loads increased the risk substantially, but few were exposed to such loads. Adjustment for lifestyle and other loads outside work did not change the results. CONCLUSION Current and past physical and psychosocial occupational factors, both separately and combined, seem to be gender-specific, and to have a moderate impact on care-seeking for low back pain in a general working population.