Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama , Japan.
Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Texas.
J Appl Physiol (1985). 2018 Nov 1;125(5):1627-1635. doi: 10.1152/japplphysiol.00502.2018. Epub 2018 Aug 30.
Posttraumatic stress disorder (PTSD) is associated with structural and functional alterations in a number of interacting brain regions, but the physiological mechanism for the high risk of cerebrovascular disease or impairment in brain function remains unknown. Women are more likely to develop PTSD after a trauma than men. We hypothesized that cerebral blood flow (CBF) regulation is impaired in women with PTSD, and it is associated with impairment in cognitive function. To test our hypothesis, we examined dynamic cerebral autoregulation (CA) and cognitive function by using a transfer function analysis between arterial pressure and middle cerebral artery blood velocity and the Stroop Color and Word test (SCWT), respectively. We did not observe any different responses in these hemodynamic variables between women with PTSD ( n = 15) and healthy counterparts (all women; n = 8). Cognitive function was impaired in women with PTSD; specifically, reaction time for the neutral task of SCWT was longer in women with PTSD compared with healthy counterparts ( P = 0.011), but this cognitive dysfunction was not affected by orthostatic stress. On the other hand, transfer function phase, gain, and coherence were not different between groups in either the supine or head-up tilt (60°) position, or even during the cognitive challenge, indicating that dynamic CA was well maintained in women with PTSD. In addition, there was no relationship between cognitive function and dynamic CA. These findings suggest that PTSD-related cognitive dysfunction may not be due to compromised CBF regulation. NEW & NOTEWORTHY Cognitive function was impaired; however, dynamic cerebral autoregulation (CA) as an index of cerebral blood flow regulation was not impaired during supine and 60° head-up tilt in women with PTSD compared with healthy females. In addition, there was no relationship between cognitive function and dynamic CA. These findings suggest that the mechanism of PTSD-related cognitive dysfunction may not be due to CBF regulation.
创伤后应激障碍（PTSD）与许多相互作用的大脑区域的结构和功能改变有关，但导致脑血管疾病风险增加或大脑功能受损的生理机制仍不清楚。女性在创伤后比男性更容易患上 PTSD。我们假设 PTSD 女性的大脑血流（CBF）调节受损，并且与认知功能障碍有关。为了验证我们的假设，我们通过动脉压与大脑中动脉血流之间的传递函数分析分别检查了动态大脑自动调节（CA）和认知功能，以及 Stroop 颜色和文字测试（SCWT）。我们没有观察到 PTSD 女性（n = 15）和健康对照组（均为女性；n = 8）之间这些血流动力学变量有任何不同的反应。PTSD 女性的认知功能受损；具体来说，SCWT 中性任务的反应时间比健康对照组更长（P = 0.011），但这种认知功能障碍不受直立应激的影响。另一方面，在仰卧或头高位倾斜（60°）位置，甚至在认知挑战期间，两组之间的传递函数相位、增益和相干性没有差异，这表明 PTSD 女性的动态 CA 得到很好的维持。此外，认知功能与动态 CA 之间没有关系。这些发现表明，与 PTSD 相关的认知功能障碍可能不是由于 CBF 调节受损所致。
值得注意的是，与健康女性相比，PTSD 女性在仰卧和 60°头高位倾斜时，其认知功能受损；然而，作为脑血流调节指标的动态大脑自动调节（CA）并未受损。此外，认知功能与动态 CA 之间没有关系。这些发现表明，与 PTSD 相关的认知功能障碍的机制可能不是由于 CBF 调节。
