Impact of Acute Antioxidant Supplementation on Vascular Function and Autonomic Nervous System Modulation in Young Adults with PTSD

Abstract

PURPOSE: Posttraumatic stress disorder (PTSD) has been associated with an increase in risk of cardiovascular disease (CVD). The goal of the study was to determine if peripheral vascular dysfunction, a precursor to CVD, was present in young adults with PTSD, and if an acute antioxidant (AO) supplementation could modify this potential PTSD-induced vascular dysfunction. METHODS: Thirteen individuals with PTSD were recruited for this investigation and were compared to 35 age- and sex-matched controls (CTRL). The PTSD group participated in two visits, consuming either a placebo (PTSD-PL) or antioxidants (PTSD-AO; Vitamins C and E; Alpha Lipoic Acid) prior to their visits, while the CRTL subjects only participated in one visit. Upper and lower limb vascular function were assessed via flow-mediated dilation and passive leg movement technique. Heart rate variability was utilized to assess autonomic nervous system modulation. RESULTS: The PTSD-PL condition, when compared to the CTRL group, reported lower arm and leg microvascular function as well as sympathetic nervous system (SNS) predominance. Following acute AO supplementation, arm, but not leg, microvascular function was improved and SNS predominance was lowered to which the prior difference between PTSD group and CTRL was no longer significant. CONCLUSION: Young individuals with PTSD demonstrated lower arm and leg microvascular function as well as greater SNS predominance when compared to age- and sex-matched controls. Furthermore, this lower vascular/autonomic function was augmented by an acute AO supplementation to the level of the healthy controls, potentially implicating oxidative stress as a contributor to this blunted vascular/autonomic function.