TY - JOUR
T1 - Early onset neurocirculatory response to static handgrip is associated with greater blood pressure variability in women with posttraumatic stress disorder
AU - Yoo, Jeung Ki
AU - Badrov, Mark B.
AU - Parker, Rosemary S.
AU - Anderson, Elizabeth H.
AU - Wiblin, Jessica L.
AU - North, Carol S.
AU - Suris, Alina
AU - Fu, Qi
N1 - Funding Information:
This study was supported by the Harry S. Moss Heart Trust award (to Q. Fu) and American Heart Association Post-Doctoral Fellowship Grant 19POST34380615 (to J. Yoo).
PY - 2020
Y1 - 2020
N2 - Posttraumatic stress disorder (PTSD) is a psychiatric illness that is more prevalent in women, and accumulating evidence suggests a link between PTSD and future development of cardiovascular disease. The underlying mechanisms are unclear, but augmented sympathetic reactivity to daily stressors may be involved. We measured muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate responses in 14 women with PTSD and 14 healthy women (controls) during static handgrip (SHG) exercise to fatigue at 40% of maximal voluntary contraction (MVC). Two minutes of postexercise circulatory arrest (PECA) was followed immediately after SHG to fatigue. MVC and the time to fatigue during SHG did not differ between groups (both P > 0.05). At the first 30 s of SHG, women with PTSD showed augmented sympathetic neural [mean ± SD, ΔMSNA burst frequency (BF): 5 ± 4 vs. 2 ± 3 bursts/30 s, P = 0.02 and ΔMSNA total activity (TA): 82 ± 58 vs. 25 ± 38 arbitrary units/30 s, P = 0.004] and pressor (Δsystolic BP: 10 ±5 vs. 4 ± 3 mmHg, P = 0.003) responses compared with controls. However, MSNA and BP responses at fatigue and during PECA were not different between groups. More interestingly, the augmented initial neural and pressor responses to SHG were associated with greater awake systolic BP variability during ambulation in women with PTSD (MSNA BF: r = 0.55, MSNA TA: r = 0.62, and SBP: r = 0.69, all P < 0.05). These results suggest that early onset exercise pressor response in women with PTSD may be attributed to enhanced mechano-rather than metaboreflexes, which might contribute to the mechanisms underlying the link between PTSD and cardiovascular risk. NEW & NOTEWORTHY The novel findings of the current study are that women with posttraumatic stress disorder (PTSD) exhibited augmented sympathetic neural and pressor responses at the first 30 s of submaximal isometric muscle contraction. More interestingly, exaggerated neurocirculatory responses at the onset of muscle contraction were associated with greater ambulatory awake systolic blood pressure fluctuations in women with PTSD. Our findings expand the knowledge on the physiological mechanisms that perhaps contribute to increased risk of cardiovascular disease in such a population. blood pressure variability; exercise pressor reflex; static hand grip; women with PTSD
AB - Posttraumatic stress disorder (PTSD) is a psychiatric illness that is more prevalent in women, and accumulating evidence suggests a link between PTSD and future development of cardiovascular disease. The underlying mechanisms are unclear, but augmented sympathetic reactivity to daily stressors may be involved. We measured muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate responses in 14 women with PTSD and 14 healthy women (controls) during static handgrip (SHG) exercise to fatigue at 40% of maximal voluntary contraction (MVC). Two minutes of postexercise circulatory arrest (PECA) was followed immediately after SHG to fatigue. MVC and the time to fatigue during SHG did not differ between groups (both P > 0.05). At the first 30 s of SHG, women with PTSD showed augmented sympathetic neural [mean ± SD, ΔMSNA burst frequency (BF): 5 ± 4 vs. 2 ± 3 bursts/30 s, P = 0.02 and ΔMSNA total activity (TA): 82 ± 58 vs. 25 ± 38 arbitrary units/30 s, P = 0.004] and pressor (Δsystolic BP: 10 ±5 vs. 4 ± 3 mmHg, P = 0.003) responses compared with controls. However, MSNA and BP responses at fatigue and during PECA were not different between groups. More interestingly, the augmented initial neural and pressor responses to SHG were associated with greater awake systolic BP variability during ambulation in women with PTSD (MSNA BF: r = 0.55, MSNA TA: r = 0.62, and SBP: r = 0.69, all P < 0.05). These results suggest that early onset exercise pressor response in women with PTSD may be attributed to enhanced mechano-rather than metaboreflexes, which might contribute to the mechanisms underlying the link between PTSD and cardiovascular risk. NEW & NOTEWORTHY The novel findings of the current study are that women with posttraumatic stress disorder (PTSD) exhibited augmented sympathetic neural and pressor responses at the first 30 s of submaximal isometric muscle contraction. More interestingly, exaggerated neurocirculatory responses at the onset of muscle contraction were associated with greater ambulatory awake systolic blood pressure fluctuations in women with PTSD. Our findings expand the knowledge on the physiological mechanisms that perhaps contribute to increased risk of cardiovascular disease in such a population. blood pressure variability; exercise pressor reflex; static hand grip; women with PTSD
UR - http://www.scopus.com/inward/record.url?scp=85076876839&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85076876839&partnerID=8YFLogxK
U2 - 10.1152/ajpheart.00490.2019
DO - 10.1152/ajpheart.00490.2019
M3 - Article
C2 - 31756119
AN - SCOPUS:85076876839
SN - 0363-6135
VL - 318
SP - H49-H58
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 1
ER -