ATF6 and post-traumatic stress disorder: For the biomarkers, we observed a clear trend: the Past PTSD ≤ 5y group consistently had the highest levels of IL-18 (125.2 ng/L vs. 30.2 in >5y), IRE1 (1608.0 pg/mL vs. 520.9), pERK (22.4 ng/L vs. 7.5), and ATF6 (24.0 ng/L vs. 7.2), with post hoc tests confirming that these levels were significantly higher in the ≤5y group compared to the >5y group (adjusted p < 0.001 for all).