In addition to the Pearson correlations, we examined Spearman rank correlations between personality and the untransformed IL-6 scores, residualized for age and sex (see Table 1). In this set of analyses, we found the same pattern of results, with a few additional significant correlations: IL-6 correlated negatively with Agreeableness and four of its facets, A1: Trust, A2: Straightforwardness, A3: Altruism, and A4: Compliance, and positively with N3: Depression, E5: Excitement-Seeking, and O4: Actions. Interestingly, the negative correlation with Agreeableness is consistent with the literature on antagonism-related constructs that shows that antagonistic individuals tend to have higher levels of IL-6. (Sjögren et al. 2006; Marsland et al. 2008).
