Are occupational factors important determinants of socioeconomic inequalities in musculoskeletal pain?
OBJECTIVE
The aim of this study was to quantify socioeconomic inequalities in low-back pain, neck-shoulder pain, and arm pain in the general working population in Oslo and to examine the impact of job characteristics on these inequalities.


METHODS
All economically active 30-, 40-, and 45-year-old persons who attended the Oslo health study in 2000-2001 and answered questions on physical job demands, job autonomy, and musculoskeletal pain were included (N=7293). Occupational class was used as an indicator of socioeconomic status. The lower occupational classes were compared with higher grade professionals, and prevalences, prevalence ratios, prevalence differences, and population attributable fractions were calculated.


RESULTS
There were marked, stepwise socioeconomic gradients for musculoskeletal pain, steeper for the men than for the women. The relative differences (prevalence ratios) were larger for low-back pain and arm pain than for neck-shoulder pain. The absolute differences (prevalence differences) were the largest for low-back pain. Physical job demands explained a substantial proportion of the absolute occupational class inequalities in low-back pain, while job autonomy was more important in explaining the inequalities in neck-shoulder pain and arm pain. The estimated population attributable fractions supported the impact of job characteristics at the working population level, especially for low-back pain.


CONCLUSIONS
In this cross-sectional study, physical job demands and job autonomy explained a substantial proportion of occupational class inequalities in self-reported musculoskeletal pain in the working population in Oslo. This finding indicates that the workplace may be an important arena for preventive efforts to reduce socioeconomic inequalities in musculoskeletal pain.
Mehlum
Ingrid Sivesind
IS
National Institute of Occupational Health, Oslo, Norway. ism@stami.no
Kristensen
Petter
P
Kjuus
Helge
H
Wergeland
Ebba
E
D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D009664:Norway / Q000453:epidemiology; D009784:Occupational Diseases / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D009790:Occupations; D010146:Pain / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D015995:Prevalence; D017009:Professional Autonomy; D012307:Risk Factors; D017678:Sex Distribution; D012923:Social Class; D013647:Task Performance and Analysis