Vanar, Vishwas

Acute systemic induced inflammation negatively affects arterial function in young healthy adults. An acute bout of aerobic exercise reduces arterial stiffness and improves endothelial function. Therefore, we evaluated endothelial function and wave reflection in older adults in response to acute systemic inflammation and the effect of moderate intensity endurance exercise immediately prior to induced inflammation. 59 healthy volunteers (range 55 – 75 years) were randomly allocated to an exercise or control group. Arterial function and inflammatory markers were measured at baseline, 24 h and 48 h after influenza vaccine and sham injections. CRP increased approximately 1.5 times, 24 and 48 h after vaccination while IL‐6 increased 24 hours after vaccination compared to the sham injection. Unexpectedly, arterial function was unaltered (Table). Inflammation and endothelial function were dissociated following vaccine‐induced acute systemic inflammation in older adults. Acute exercise prior to vaccination had no effect of inflammation or vascular function. Support: AHA #10PRE3500083 (SMR).

New Findings What is the central question of this study? The aim of the study was to evaluate the effect of acute induced systemic inflammation on endothelial function, wave reflection and arterial function in older adults. What is the main finding and its importance? Acute inflammation induced by influenza vaccination did not affect endothelial function in older adults. These findings have never been shown in older adults, and they emphasize the importance of vascular function during systemic arterial inflammation. Acute inflammation reduces flow‐mediated vasodilatation and increases arterial stiffness in young healthy individuals. However, this response has not been studied in older adults. The aim of this study, therefore, was to evaluate the effect of acute induced systemic inflammation on endothelial function and wave reflection in older adults. Furthermore, an acute bout of moderate‐intensity aerobic exercise can be anti‐inflammatory. Taken together, we tested the hypothesis that acute moderate‐intensity endurance exercise, immediately preceding induced inflammation, would be protective against the negative effects of acute systemic inflammation on vascular function. Fifty‐nine healthy volunteers between 55 and 75 years of age were randomized to an exercise or a control group. Both groups received a vaccine (induced inflammation) and sham (saline) injection in a counterbalanced crossover design. Inflammatory markers, endothelial function (flow‐mediated vasodilatation) and measures of wave reflection and arterial stiffness were evaluated at baseline and at 24 and 48 h after injections. There were no significant differences in endothelial function and arterial stiffness between the exercise and control group after induced inflammation. The groups were then analysed together, and we found significant differences in the inflammatory markers 24 and 48 h after induction of acute inflammation compared with sham injection. However, flow‐mediated vasodilatation, augmentation index normalized for heart rate (AIx75) and β‐stiffness did not change significantly. Our results suggest that acute inflammation induced by influenza vaccination did not affect endothelial function in older adults.