Background
Posttraumatic stress disorder (PTSD) may contribute to heightened cardiovascular disease (CVD) risk by promoting a pro-inflammatory state and impaired endothelial function. Prior research has demonstrated associations of PTSD with inflammatory and endothelial function biomarkers, but most work is cross-sectional and does not separate effects of trauma exposure from those of PTSD.
Methods
We investigated associations of trauma exposure and chronic PTSD with biomarkers of inflammation [C-reactive protein (CRP); tumor necrosis factor-alpha receptor-II (TNFRII)] and endothelial function [intercellular adhesion molecule-1 (ICAM-1); vascular cell adhesion molecule-1 (VCAM-1)] in 524 middle-aged women in the Nurses’ Health Study II. Using linear mixed models, we examined associations of trauma/PTSD status with biomarkers measured twice, 10–16 years apart, in CVD-free women, considering either average levels over time (cross-sectional) or change in levels over time (longitudinal). Biomarker levels were log-transformed. Trauma/PTSD status (based on structured diagnostic interviews) was defined as no trauma at either blood draw (n=175), trauma at draw 1 but no PTSD at either draw (n=175), and PTSD that persisted beyond draw 1 (chronic PTSD; n=174). The reference group was women without trauma.
Results
In models adjusted for known potential confounders, women with chronic PTSD had higher average CRP (b=0.27, p<.05), TNFRII (b=0.07, p<.01), and ICAM-1 (b=0.04, p<.05) levels. Women with trauma but without PTSD had higher average TNFRII levels (b=0.05, p<.05). Furthermore, women with chronic PTSD had a greater increase in VCAM-1 over time (b=0.003, p<.05).
Conclusions
Increased inflammation and impaired endothelial function may be pathways by which chronic PTSD increases CVD risk.