Interleukin-6 and soluble interleukin-6 receptor levels in posttraumatic stress disorder: associations with lifetime diagnostic status and psychological context

Abstract

This study correlated lifetime PTSD diagnostic status with interleukin-6 (IL-6) and soluble IL-6 receptor (sIL-6R) levels, and tested whether these correlations are sensitive to psychological context. Midlife women attended two research visits where blood was drawn (beginning of visits) and saliva and oral mucosal transudate were collected (beginning and end of visits) to measure IL-6 and sIL-6R. Women were classified as PTSD-/- (past and current symptoms below subsyndromal levels), PTSD+/- (past symptoms at or above subsyndromal levels), or PTSD+/+ (past and current symptoms at or above subsyndromal levels). PTSD+/+ women, compared to the other women, showed more negative emotion at the beginning of the visits, higher salivary IL-6 levels at the beginning versus end of visits, and positive correlations between negative emotion, salivary IL-6, and plasma sIL-6R. Their plasma sIL-6R levels exceeded those of the PTSD+/- women. Overall, IL-6 sensitivity to anticipation and to negative emotions, and higher sIL-6R levels, differentiated persistent versus remitted PTSD.

Keywords: Anticipation; IL-6; Inflammation; PTSD; Remitted PTSD; sIL-6R.