Longitudinal Associations Between Peritraumatic Oestradiol and Fear Responding in Women and Men.

PTSD is more prevalent in women than men and associated with autonomic dysfunction. Higher oestradiol levels have been associated with decreased PTSD severity, however, the impact of oestradiol on autonomic function is not well characterised. We examined associations among peritraumatic oestradiol levels and autonomic function in the multi-site AURORA study. Participants (n = 283, 69.6% female) were recruited from the emergency department (ED) following trauma exposure. Skin conductance (SC) was measured during trauma recall at the ED. Oestradiol was assayed from blood collected at ED, 2-week and 6-month. Fear conditioning, including fear potentiated startle (FPS), was completed at 2-week and 6-month. In women, ED oestradiol was significantly positively associated with ED SC and FPS at 6-month. In men, significant negative correlations between ED oestradiol and SC were found. Among women in the study, peritraumatic oestradiol was positively associated with fear responding 6-month. Findings suggest that the protective effects of oestradiol on PTSD may depend on other factors, such as time since trauma. Additional research is needed to elucidate how peritraumatic oestradiol and autonomic function may interact to confer risk for PTSD.