Objective: To examine whether shift work is a risk factor for low back pain (LBP) and the interaction effects of shift work and overweight/obesity on LBP over time among nurses.
Methods: A longitudinal study over 2 years. Measurements included reported LBP, shift work status, and selected potential confounders.
Results: Among 928 LBP-free nurses at baseline, 319 (34.4%) developed LBP over 2 years. After adjusting for confounders, shift workers were 1.15 times more likely to develop LBP (adjusted odds ratio [aOR], 1.15; 95% confidence interval, 1.05 to 1.40; P = 0.03). The interaction analysis showed that overweight/obese shift workers were more likely to develop LBP than day workers (overweight: aOR, 1.23 vs aOR, 1.03, respectively; obesity: aOR, 1.34 vs aOR, 1.10, respectively).
Conclusions: Our findings suggest that shift workers are at a higher risk of developing LBP over time, especially those who are overweight/obese.