The effect of season on the mood, concentration of interleukin‐6, adrenocorticotrophic hormone, metabolites of catecholamine and cortisol level in healthy volunteers.

Abstract

We investigated seasonal changes in interleukin‐6 (IL‐6), adrenocorticotrophic hormone (ACTH), metabolites of catecholamine (VMA, HVA, and 5‐HIAA) and cortisol in humans. Eight volunteers were investigated at four times during the year at latitude 35°N (i.e., February, May, August and November). The mean atmospheric temperature in the collection periods was higher in the order of summer > autumn ≈ spring > winter. Changes in mood were also monitored by a profile of mood states (POMS) questionnaire. The concentration of IL‐6 was significantly higher in the winter and summer than in the spring and autumn. The concentrations of ACTH, HVA and VMA were significantly higher in summer. No seasonal variation was detected in cortisol. There were significant differences among the seasons in the subscale for tension and anger in the POMS questionnaire; the tension subscale showed significant differences between spring and autumn, with a higher score in spring. The results demonstrate that Il‐6, ACTH, HVA and VMA exhibit statistically significant seasonal rhythms, which might have important diagnostic and therapeutic implications.