Higher arterial stiffness and blunted vagal control of the heart in young women with compared to without a clinical diagnosis of PTSD

Abstract

Purpose: Young women are typically thought to be protected from cardiovascular disease (CVD) before menopause. However, posttraumatic stress disorder (PTSD) increases CVD risk in women by up to threefold. Data in predominantly male cohorts point to physiological mechanisms such as vascular and autonomic derangements as contributing to increased CVD risk. The purpose of the study reported here was to determine whether young women diagnosed with PTSD, compared to those without, present with arterial stiffness and impaired autonomic control of the heart.

Methods: A total of 73 healthy young women, ranging in age from 18 to 40 years, with a history of trauma exposure were included in this study, 32 with and 41 without a clinical PTSD diagnosis. We measured resting pulse wave velocity (PWV), central hemodynamics, augmentation pressure and augmentation index (AI) via pulse wave analysis using applanation tonometry. Heart rate variability was also assessed via peripheral arterial tone.

Results: In comparison to controls, women with PTSD showed higher central arterial pressure (mean ± standard deviation: systolic blood pressure 104 ± 8 vs. 97 ± 8 mmHg, p < 0.001; diastolic blood pressure 72 ± 7 vs. 67 ± 7 mmHg, p = 0.003), PWV (6 ± 0.3 vs. 5 ± 0.6 m/s, p < 0.001) and AI (22 ± 13 vs. 15 ± 12%, p = 0.007) but lower standard deviation of normal-to-normal intervals (SDNN; 44 ± 17 vs. 54 ± 18 ms, p = 0.005) and root mean square of successive differences between normal heartbeats (RMSSD; 37 ± 17 vs. 51 ± 22 ms, p = 0.002).

Conclusion: PTSD in young women is associated with higher brachial and central pressures, increased arterial stiffness and blunted parasympathetic control of the heart. These findings illustrate potential mechanisms underlying high risk for CVD in young women with PTSD, suggesting possible treatment targets for this at-risk group.

Keywords: Arterial stiffness; Central arterial pressure; PTSD; Women; Young.

Figure 1.

Brachial systolic and diastolic blood pressure (panel A and B) in 32 women with PTSD (PTSD+) and 41 trauma-exposed women without PTSD (PTSD-). Baseline heart rate (panel C) was also measured in 32 PTSD+ and 41 PTSD-. An independent t-test was used to compare the two groups. Women with PTSD had significantly elevated brachial arterial pressure and heart rate compared to women without PTSD.

Figure 2.

Central (aortic) systolic and diastolic arterial pressure (panel A and B) in 32 women with PTSD (PTSD+) and 41 trauma-exposed women without PTSD (PTSD-). Aortic augmentation pressure (panel C) was also measured in 32 PTSD+ women and 41 PTSD− women. An independent t-test was used to compare the two groups. Women with PTSD had significantly elevated aortic systolic and diastolic arterial pressures, as well aortic augmentation pressure compared to women without PTSD.

Figure 3.

Pulse wave velocity (panel A), augmentation index (panel B), as well as augmentation index normalized to 75 bpm (panel C) was obtained from 32 women with PTSD (PTSD+) and 41 trauma-exposed women without PTSD (PTSD-). An independent t-test was used to compare the two groups. Women with PTSD had significantly elevated pulse wave velocity and augmentation index compared to women without PTSD.

Figure 4.

Resting time domains of heart rate variability [standard deviation of normal R-R intervals (SDNN) (panel A) and root mean square of the successive differences (RMSSD) (panel B)] was measured in 32 women with PTSD (PTSD+) and 41 trauma-exposed women without PTSD (PTSD-). An independent t-test was used to compare the two groups. Women with PTSD had significantly lower SDNN and RMSSD compared to women without PTSD.