Exaggerated Peripheral and Systemic Vasoconstriction During Trauma Recall in Posttraumatic Stress Disorder: A Co-Twin Control Study

Abstract

Background: Individuals with posttraumatic stress disorder (PTSD) face an increased risk of cardiovascular disease, but the mechanisms linking PTSD to cardiovascular disease remain incompletely understood. We used a co-twin control study design to test the hypothesis that individuals with PTSD exhibit augmented peripheral and systemic vasoconstriction during a personalized trauma recall task.

Methods: In 179 older male twins from the Vietnam Era Twin Registry, lifetime history of PTSD and current (last month) PTSD symptoms were assessed. Participants listened to neutral and personalized trauma scripts while peripheral vascular tone (Peripheral Arterial Tone ratio) and systemic vascular tone (e.g., total vascular conductance) were measured. Linear mixed-effect models were used to assess the within-pair relationship between PTSD and vascular tone indices.

Results: The mean age of participants was 68 years, and 19% had a history of PTSD. For the Peripheral Arterial Tone ratio analysis, 32 twins were discordant for a history of PTSD, and 46 were discordant for current PTSD symptoms. Compared with their brothers without PTSD, during trauma recall, participants with a history of PTSD had greater increases in peripheral (β = -1.01, 95% CI [-1.72, -0.30]) and systemic (total vascular conductance: β = -1.12, 95% CI [-1.97, -0.27]) vasoconstriction after adjusting for cardiovascular risk factors. Associations persisted after adjusting for antidepressant medication use and heart rate and blood pressure during the tasks. Analysis of current PTSD symptom severity showed consistent results.

Conclusions: PTSD is associated with exaggerated peripheral and systemic vasoconstrictor responses to traumatic stress reminders, which may contribute to elevated risk of cardiovascular disease.

Keywords: Cardiovascular disease; Cardiovascular health disparity; Cardiovascular reactivity; Hypertension; Idiographic trauma cues; Psychological stress.

Figure 1.

General psychological and cardiovascular responses to neutral and trauma script listening in non-PTSD (n = 154) and PTSD (n = 36) participants. A) Subjective distress. B) Heart rate. C) Systolic blood pressure. D) Diastolic blood pressure. Data are presented as mean ± 95%CI. * p < 0.05 vs. Rest (both groups). § p < 0.05 vs. Rest (designated group only). † p < 0.05 Between groups.

Figure 2.

Standardized peripheral and systemic vasoconstriction responses to trauma script listening in PTSD-discordant twins. A) Peripheral vasoconstriction indexed by the PAT ratio in 32 PTSD-discordant twins. B) Systemic vasoconstriction indexed by SVR reactivity in 22 PTSD-discordant twins. C) Systemic vasoconstriction indexed by TVC reactivity in 22 PTSD-discordant twins. Data are presented as the mean standardized within twin pair difference ± 95%CI, adjusted for cardiovascular disease history (hypertension and coronary heart disease) and risk factors (BMI, smoking, and physical activity) and antidepressant medication use. PTSD, post-traumatic stress disorder; PAT Ratio, peripheral arterial tonometry ratio (smaller values indicate greater vasoconstriction during trauma script listening); SVR, systemic vascular resistance (higher values indicate greater vasoconstriction during trauma script listening); TVC, total vascular conductance (lower values indicate greater vasoconstriction during trauma script listening) * p < 0.05; ** p < 0.01.