Associated factors of low back pain classified by severity and chronicity among care workers: A cross-sectional study

Background Low back pain (LBP) is a major occupational health problem among care workers. However, few studies have classified LBP by both severity and chronicity or examined associations of health literacy with presenteeism. This study aimed to assess LBP prevalence, classify LBP by severity and chronicity, and identify the associated physical and psychosocial factors. We conducted a secondary exploratory analysis to examine hypothesized indirect associations between health literacy and presenteeism involving psychological distress and LBP-related disability. Methods A cross-sectional survey was conducted among 1022 care workers employed at long-term care facilities. Participants were categorized into five groups: non-LBP and four LBP groups defined by severity (non-severe vs. severe) and chronicity (non-chronic vs. chronic). Sociodemographic, work-related, health literacy, and psychosocial factors were analyzed using multinomial logistic regression. The secondary exploratory analysis examined the hypothesized indirect statistical associations using psychological distress and LBP-related disability. Results The prevalence of LBP was 75%. Severity and chronicity were not fully concordant, supporting classification by both dimensions. Unsuitable posture was associated with all LBP groups. Severe LBP was associated with higher psychological distress and greater presenteeism, whereas low health literacy was independently associated with severe chronic LBP. The secondary exploratory analysis identified significant indirect associations of health literacy with presenteeism involving psychological distress and LBP-related disability. Conclusions LBP among care workers is highly prevalent and multifactorial. The factors associated with LBP differed according to severity and chronicity, highlighting the importance of considering both dimensions together with physical and psychosocial factors when assessing LBP among care workers.