[Effects of occupational stress on serum tumor necrosis factor-α and interleukins]

To explore the effect of occupational stress on serum tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-2 and IL-4.

A cross-sectional epidemiological study was conducted in 200 workers from the refrigerator assembly line in Henan province in China. Psychosocial work conditions were measured by using the job demand-control model, the effort-reward imbalance model questionnaires and occupational stress measurement scale. Serum TNF-α, IL-1β, IL-2, and IL-4 concentrations were measured by radioimmunoassay or immunoradiometric assay method respectively.

Serum TNF-α concentration was statistically significantly different between workers with higher affective balance level and control groups [(1.947 ± 0.173) and (2.029 ± 0.240) fmol/ml] (P < 0.05). Serum IL-1β concentration was statistically significantly different between workers with higher effort level and control groups [(0.133 ± 0.034) and (0.118 ± 0.031) ng/ml] (P < 0.05). Serum IL-2 concentration was statistically significantly different between workers with higher role ambiguity level [(1.658 ± 0.376) and (1.491 ± 0.033) ng/ml] and control groups (P < 0.05), as well as between workers with higher role conflict level and control groups [(1.774 ± 0.311) and (1.589 ± 0.380) ng/ml] (P < 0.05), between workers with higher daily life stress level and control groups [(1.759 ± 0.361) and (1.606 ± 0.381) ng/ml] (P < 0.05). Serum IL-4 concentration was statistically significantly different between workers with higher reward level and control groups [(1.449 ± 0.025) and (1.466 ± 0.041) pg/ml] (P < 0.05). Stepwise regression analysis indicated that affective balance was the predictor of serum TNF-α (R(2) = 0.029). Effort and mental health were the predictors of serum IL-1β (R(2) was 0.029 and 0.055, respectively). Role conflict, daily life stress and role ambiguity were the predictors of serum IL-2 (R(2) was 0.040, 0.078 and 0.104, respectively). Reward was the predictor of serum IL-4 (R(2) = 0.030).

Unhealthy psychological stress factor might be induce a marked increase in the concentrations of serum TNF-α, IL-1β, IL-2, as well as IL-4.