Factors and their age differences associated with low back pain among Japanese workers: a cross-sectional study

This study aimed to examine the factors and their age differences associated with low back pain (LBP), including lifestyle and psychosocial factors, among Japanese workers at a large company. The study population consisted of 25,610 workers (mean ± SD age, 44.7 ± 9.6 yr) who underwent annual health checkups and completed the Brief Job Stress Questionnaire (BJSQ) at a Japanese company in 2017. The self-administered questionnaire was used to assess gender, age, occupation, smoking status, exercise status, alcohol intake, job stress, and sleep duration. LBP presence was assessed using a part of the BJSQ. Multivariable-adjusted logistic regression analyses were performed to examine the factors associated with LBP according to age category. The prevalence of LBP in the study group was 23.3%. After stratification by age, overweight status and job stress were found to be significantly associated with LBP in all age groups. However, smoking status was significantly associated with LBP among individuals aged <40 yr (effect of interaction p=0.03) whereas exercise was significantly associated only among individuals aged ≥40 yr (effect of interaction p<0.01). This study shows that LBP factors may differ by age, highlighting the importance of age-appropriate measures for preventing LBP in workers.