Sport-related concussion induces transient cardiovascular autonomic dysfunction.
Recent evidence suggests that concussions may disrupt autonomic cardiovascular control. This study investigated the initial effects of concussion on cardiovascular function using three autonomic reflex tests. Twenty-three recreational athletes (12 women, 11 men) were divided into concussed (n= 12) and control (n= 11) groups. Concussed participants performed forced breathing, standing, and Valsalva autonomic tests four times:1) within 48 h of injury;2) 24 h later;3) 1 wk after injury; and4) 2 wk after injury. The controls performed the same tests on the same schedule. Differences in heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) responses to the tests were continuously measured using finger photoplethysmography and were analyzed using repeated-measures multivariate ANOVAs and ANOVAs. Within 48 h of injury, the concussed group had significantly greater resting SBP (t21= 2.44,P= 0.02,d= 1.03), HR (t21= 2.33,P= 0.03,d= 1.01), and SBP responses to standing (t21= 2.98,P= 0.01,d= 1.24), and 90% SBP normalization times (t21= 2.64,P= 0.02,d= 1.10) after the Valsalva, but those group differences subsided 24 h later. There was also a significant interaction with the HR responses to forced breathing (F3,60= 4.13,P= 0.01, ηp2= 0.17), indicating the concussed responses declined relative to the control's over time. The results demonstrate that concussion disrupted autonomic cardiovascular control, and that autonomic reflex tests are practical means by which to evaluate that dysfunction.
School of Health and Kinesiology, Georgia Southern University, Statesboro, Georgia; jdobson@georgiasouthern.edu.
John L
JL
Dobson
School of Health and Kinesiology, Georgia Southern University, Statesboro, Georgia.
Mary Beth
MB
Yarbrough
School of Health and Kinesiology, Georgia Southern University, Statesboro, Georgia.
Jose
J
Perez
School of Health and Kinesiology, Georgia Southern University, Statesboro, Georgia.
Kelsey
K
Evans
Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware; and.|Interdisciplinary Program in Biomechanics and Movement Science, University of Delaware, Newark, Delaware.
Thomas
T
Buckley
D001265:Athletic Injuries / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D001794:Blood Pressure; D001924:Brain Concussion / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D003937:Diagnosis, Differential; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D055815:Young Adult
autonomic; brain injury; cardiovascular; concussion