Association between objectively measured sitting time and neck-shoulder pain among blue-collar workers.

OBJECTIVES: Prolonged sitting has been suggested as a risk factor for neck-shoulder pain (NSP). Using a cross-sectional design, we investigated the extent to which objectively measured time sitting is associated with NSP among blue-collar workers.

METHODS: Sitting time was measured during multiple working days on male (n = 118) and female (n = 84) blue-collar workers (n = 202) using triaxial accelerometers (Actigraph) placed on the thigh and trunk. Workers were categorized into having, on average, a low, moderate or high sitting time, with mean values (SD between subjects) of 4.9 (1.0), 7.3 (0.5) and 9.6 (1.1) h in total per day. Workers rated their largest NSP intensity during the previous month on a numerical scale (0-9) and were subsequently dichotomized into a low and high NSP intensity group (ratings 0-4 and >4, respectively). Logistic regression analyses adjusted for several individual, and work-related factors were used to investigate the association between average sitting time per day (work, leisure and total) and NSP intensity.

RESULTS: For total sitting time, workers in the high sitting category were more likely (adjusted OR 2.97, CI 1.25-7.03) to report high NSP intensity than those who sat moderately (reference category). Low sitting during work was associated with a reduced NSP intensity, but only for males (adjusted OR 0.26 CI 0.07-0.96). No significant association was found between sitting during leisure and NSP intensity.

CONCLUSION: These findings suggest an association between sitting time, in total per day and specifically during work, and NSP intensity among blue-collar workers. We encourage studying the structure and explanation of this association further in prospective studies on larger populations.