2021/04/28 by Stacey E. Aaron, Jason W. Hamner, Erin D. Ozturk +5
paper · doi:10.1002/ana.26082
Objective To assess acute cerebrovascular function in concussed adolescents (14–21 years of age), whether it is related to resting cerebral hemodynamics, and whether it recovers chronically. Methods Cerebral vasoreactivity and autoregulation, based on middle cerebral artery blood flow velocity, was assessed in 28 concussed participants (≤14 days of injury) and 29 matched controls. The participants in the concussion group returned for an 8‐week follow‐up assessment. Over the course of those 8‐weeks, participants recorded aerobic exercise frequency and duration. Results Between groups, demographic, clinical, and hemodynamic variables were not significantly different. Vasoreactivity was significantly higher in the concussed group ( p = 0.02). Within the concussed group, 60% of the variability in resting cerebral blood flow velocity was explained by vasoreactivity and two components of autoregulation – falling slope and effectiveness of autoregulation (adjusted R 2 = 0.60, p R 2 = 0.72, p p R 2 = 0.19, p = 0.02). Interpretation Concussion resulted in changes in cerebrovascular regulatory mechanisms, which in turn explained the variability in resting cerebral blood flow velocity and acute symptom burden. Furthermore, these alterations persisted chronically despite symptom resolution, but was positively modified by aerobic exercise volume. These findings provide a mechanistic framework for further investigation into underlying cerebrovascular related symptomatology. ANN NEUROL 2021;90:43–51