Counter-stress effects of relaxation on proinflammatory and anti-inflammatory cytokines.

The counter-stress effects of relaxation on proinflammatory and anti-inflammatory cytokines were examined. From 36 medical students, 18 were randomly assigned to the relaxation group, and 18 were randomly assigned to the non-relaxation group. Relaxation lasted for four weeks. The levels of stimulated production of IL-6, TNF-alpha, and IL-10, and blood pressure were measured during the non-examination period (baseline period) and the pre-examination period (stress period). The levels of perceived stress were assessed by the Global Assessment of Recent Stress (GARS) scale, the Stress Response Inventory (SRI) and the Symptom Checklist-90-Revised (SCL-90-R) anxiety subscale. Repeat measure ANOVA revealed that the SRI total score, scores of the SCL-90-R anxiety subscale and diastolic blood pressure were significantly higher during the stress period than during the baseline period regardless of groups. The level of IL-6 production was significantly lower but the level of IL-10 production was significantly higher during the stress period than during the baseline period. Significant reduction in the delta (stress period value minus baseline period value) in the total GARS score, systolic and diastolic blood pressure, the levels of IL-6 and TNF-alpha production but significant enhancement in the delta in the level of the IL-10 production were found in the relaxation group compared with the non-relaxation group. These results suggest that relaxation is associated with reduction in stress-induced psychological or physiological responses and proinflammatory cytokine alterations but with enhancement in stress-induced anti-inflammatory cytokine alteration. Therefore, relaxation is more likely to have counter-stress effect on proinflammatory cytokines than on anti-inflammatory cytokine.