(752.5) Cardiovascular and Sympathetic Neural Responses to Cognitive Tasks in Women with Posttraumatic Stress Disorder

Poster Board Number: E424

Takuro Washio (Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital), Jeung-Ki Yoo (Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital), Elizabeth H. Anderson (University of Texas Southwestern Medical Center, University of Texas Southwestern Medical Center), Ryosuke Takeda (Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital), Sarah Hissen (Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital), Michael Nelson (University of Texas at Arlington), Carol North (University of Texas Southwestern Medical Center, University of Texas Southwestern Medical Center), Alina Suris (University of Texas Southwestern Medical Center, University of Texas Southwestern Medical Center), Qi Fu (Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital)

Background: Posttraumatic stress disorder (PTSD) is more prevalent in women than men and is associated with an increased risk for dementia. Indeed, we previously showed that cognitive function is impaired in women with PTSD, but the underlying mechanisms remain unknown. In patients with mild cognitive impairment, the cardiovascular response during cognitive tasks have been shown to be blunted. Thus, we hypothesized that cardiovascular and sympathetic neural responses to a cognitive task would be smaller in women with PTSD than healthy women. 

Methods: We measured heart rate (HR), mean arterial pressure (MAP), cardiac output (CO, Modelflow), total peripheral resistance (TPR = MAP/CO), and muscle sympathetic nerve activity (MSNA, microneurography) in 16 women with PTSD (42 ± 11 [SD] yrs) and 9 age-matched healthy women (controls; 41 ± 9 yrs) during 3 min of the Stroop Color and Word Test (SCWT) in the supine position. 

Results: In response to SCWT, HR, MAP, and CO increased (all P lt; 0.001) but TPR remained unchanged (P = 0.753) in both groups. Increases (Δ) in HR (6 ± 4 vs. 11 ± 6 bpm) and CO (0.6 ± 0.6 vs. 0.9 ± 0.4 L/min) during SCWT were smaller in PTSD than controls (both P lt; 0.05), while ΔMAP was similar between groups (P = 0.169). MSNA burst frequency and incidence were significantly higher in women with PTSD than controls at baseline and throughout SCWT (P = 0.003), but ΔMSNA during SCWT was similar between groups.

Conclusions: Cardiovascular, but not sympathetic neural responses to SCWT were blunted in women with PTSD. Our findings suggest that cognitive impairment in women with PTSD may be related to the insufficient cardiac response rather than sympathetic vasoconstriction during cognitive tasks.

Supported by Harry S. Moss Heart Trust award.