Exploring Pathways Linking Work and Nonwork Factors to Sleep, Fatigue, and Health in Night Shift Nurses: A Structural Equation Modeling Analysis

Background: Night shift work disrupts sleep and physiological recovery, leading to adverse health outcomes among nurses. While both work and nonwork factors are known to influence sleep and fatigue, few studies have examined their simultaneous and multiple mediating effects on health in night shift nurses. Aim: This study tested a comprehensive model to investigate the relationships among work factors (emotional demands, night shift rotation intervals, and social support), nonwork factors (exercise and work–life interference), sleep disturbance, fatigue, and health in night shift nurses. Methods: A cross-sectional study was conducted with 289 nurses working rotating night shifts at three hospitals in South Korea. Structural equation modeling (SEM) was employed to assess the direct and indirect effects between variables. Data were collected using validated instruments for sleep disturbance, fatigue, emotional demands, social support, exercise, work–life interference, and health. Results: Work–life interference had the most significant effect on health, both directly and indirectly through sleep disturbance and fatigue. Emotional demands negatively influenced health via sleep disturbance and fatigue. Exercise indirectly improved health by reducing fatigue, but showed no direct effects. Sleep disturbance was a significant predictor of both fatigue and health. Social support did not demonstrate significant direct or indirect effects on health. The final model explained 51.8% of the variance in health outcomes and exhibited strong model fit indices. Conclusion: Maintaining a work–life balance is critical for improving the health of night shift nurses, as work–life interference directly and indirectly exacerbates health risks through sleep disturbance and fatigue. Implications for Nursing Management: These findings highlight the importance of implementing strategies to manage work–life balance, address emotional demands, promote physical activity, and ensure recovery from shift work to support the health of night shift nurses.