Introduction

Prolonged occupational sitting has been suggested to be a risk factor for neck-shoulder pain (NSP). However, studies using valid and precise methods for assessing sitting are lacking. We investigated the extent to which objectively measured sitting time is associated with intense NSP among blue-collar workers.

Methods

In a cross-sectional study, sitting time was measured for two working days on male (n=118) and female (n=84) blue-collar workers using tri-axial accelerometers (Actigraph) placed on the thigh and trunk. Workers were categorized in tertiles having low, moderate, or high sitting time at work. Workers rated their NSP intensity during the previous month on a numerical scale (0-9), and were then dichotomized into a low (0-4) and high (>4) NSP intensity group. Binary logistic regression analyses, with multiple adjustments for individual and occupational risk factors besides sitting, were performed to investigate the association between occupational sitting time and intense NSP, separately for males and females.  

Results

We found that low occupational sitting was associated with a reduced NSP intensity compared to moderate sitting among males (OR 0.28, 95%CI 0.08-0.98). This association remained significant after adjustment for individual and occupational covariates (adjusted OR 0.26, 95%CI 0.07-0.96). We found no such relationship among females (OR 1.01, 95%CI 0.28-3.59), and high sitting was not associated with pain.

Conclusion

Our findings suggest a gender-specific association between occupational sitting time and intense NSP among blue-collar workers. We encourage further studies to investigate the nature of this association, using prospective designs in larger, gender-stratified populations.