Exploring factors associated with inflammation in stressed workers: a cross-sectional study

Chronic occupational stress leads to physical and mental illnesses, highlighting the importance of effective stress management in modern societies. Recently, chronic stress-induced systemic low-grade inflammation has garnered increasing attention for its stress response and crucial pathological role in the development of both physical and mental illnesses. In this context, elevated salivary interleukin-6 (sIL-6) levels have been developed as measurable and non-invasive stress indicators. However, the factors associated with sIL-6 in stressed office workers, including the symptomatic manifestations of stress responses, have not been extensively investigated. Since direct measurement of inflammation is costly in routine stress management, identifying symptoms that reliably reflect inflammation could facilitate the development of more effective, inflammation-based stress management strategies.

In this cross-sectional study, stressed office workers were recruited through a screening process using a Brief Job Stress Questionnaire. Saliva samples were collected to measure sIL-6 levels, and participants completed questionnaires addressing their occupational environment, symptomatic manifestations, and lifestyle. After excluding one participant owing to a medical history that could potentially affect sIL-6 levels, 128 stressed office workers were included in the analysis.

Our model-based analysis for symptomatic manifestation demonstrated that elevated sIL-6 was significantly associated with greater feelings of fatigue as well as relatively higher vigor. A separate model-based analysis for stressors revealed a significant association with higher qualitative job overload. Data-driven analyses further supported the finding that elevated sIL-6 was significantly associated with fatigue.

Our findings suggest that the feeling of fatigue may reflect chronic stress-induced systemic low-grade inflammation in the body, highlighting the importance of self-monitoring fatigue for early intervention. Inflammation-based stress management holds promise in preventing both mental and physical illnesses in stressed office workers.