Case Report ARTICLE
Bidirectional cause-effect relationship between urinary interleukin-6 and mood, irritation and mental activity in a breast cancer survivor
- 1Clinical Department of Medical Psychology, Innsbruck Medical University, Austria
- 2Department for Neurology, Universitätsklinikum Tulln, Austria
This ‘integrative single-case study’ (Schubert et al., 1999) investigated the bidirectional cause and effect relations between various emotional states (i.e. mood, irritation, mental activity) and urinary IL-6 levels in a 49-year-old female breast cancer survivor (woman) under conditions of ‘life as it is lived’. During a period of 28 days, the patient collected her entire urine in 12hour intervals for IL-6 measurement and completed each morning and evening a list of adjectives regarding mood, irritation and mental activity (55 measurements in total). Autoregressive integrated moving average modeling revealed a 4-day (circasemiseptan) cycle in the IL-6 time series. Furthermore, cross-correlational analyses after controlling for serial dependencies (significance level: p < 0.05) showed that worsening in mood and increases in irritation were followed by increases in urinary IL-6 levels with temporal delays between 12 and 36 h. In the opposite direction of effect, increases in urinary IL-6 levels were followed by elevations in mood and mental activity as well as decreases in irritation with temporal delays between 48 and 72 h. These results from cross-correlational analyses suggest that IL-6 may have a regulatory function in psychoneuroimmunological interplay and that, under certain conditions, IL-6 may be involved in health rather than sickness behavior. Moreover, the findings of this study are indicators of real-life negative feedback loops and are in line with psychoneuroimmunological research postulating complex brain-to-body-to-brain network-like structures.
Keywords: Cancer, Interleukin-6, Time Series Analyses, single-case design, Brain-to-body-to-brain, emotion
Received: 07 Feb 2018;
Accepted: 29 Oct 2018.
Edited by:Pierrette Gaudreau, Université de Montréal, Canada
Reviewed by:Stephen Kent, La Trobe University, Australia
Tamas Fulop, Université de Sherbrooke, Canada
Copyright: © 2018 Schubert and Hagen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Christian Schubert, Innsbruck Medical University, Clinical Department of Medical Psychology, Innsbruck, Austria, email@example.com