Low Back Pain and Psychosocial Work Factors Associated with Sleep Problems among University and Hospital Employees: A Cross-sectional Study

Abstract

Introduction: Sleep problems are common among healthcare workers, but associated factors among employees at a medical university and its affiliated hospital remain incompletely understood. This study examined psychosocial and clinical factors associated with sleep problems, with particular attention to low back pain (LBP). Methods: We conducted a cross-sectional, web-based survey of 2,450 employees from a medical university and its affiliated hospital using Brief Job Stress Questionnaire data from Japan’s legally mandated stress-check program in 2022. Sleep problems and LBP were assessed using single items. Age group, job category, body mass index, psychosocial work factors, other physical and psychological symptoms, and job and life satisfaction were also obtained. Group comparisons were performed between participants with and without sleep problems, and multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results: Of 2,450 participants, 472 (19.3%) had sleep problems. In multivariable analyses adjusted for job category, LBP remained independently associated with higher odds of sleep problems (adjusted OR 1.16, 95% CI 1.03-1.30). Poor gastrointestinal condition, constipation or diarrhea, interpersonal stress at work, fatigue, and depressive mood were also independently associated with higher odds of sleep problems, whereas job and life satisfaction was associated with lower odds. In the dose–response analysis, the adjusted ORs for sleep problems increased across LBP categories after adjustment for job category and other covariates, with a significant linear trend (p for trend = 0.014). Conclusions: Among employees at a medical university and its affiliated hospital, LBP showed an independent and dose–response association with sleep problems after accounting for psychosocial work factors, clinical stress-related symptoms, and job category. By simultaneously evaluating musculoskeletal symptoms and psychosocial occupational factors in a large multiprofessional workforce, this study supports integrated occupational health approaches targeting both LBP and modifiable workplace factors.