Abstract 17121: Elevated Aortic Stiffness and Impairments in Cerebrovascular Regulation in Cancer Survivorship

Abstract

Background: Approximately 46% of cancer survivors report cognitive impairments across many types of cancer, which has been associated with anti-cancer therapy and often results in reduced quality of life. Pre-clinical studies suggest that predictors of cognitive decline may involve vascular dysfunction. We aimed to characterize local (cerebrovascular reactivity and cerebral autoregulation) and global (aortic arch stiffness) vascular regulation in cancer survivorship. Methods: Cerebral autoregulation was determined using Mx, a moving 10s-windowed correlation between finger plethysmography-derived blood pressure and cerebral blood velocity of the middle cerebral artery. Higher Mx values represent pressure-passive cerebral blood flow, indicating poor cerebral autoregulation. In addition, cerebral blood velocity, blood pressure, and end-tidal CO 2 were collected during a rebreathing task. MAP was used to calculate an index of cerebrovascular conductance (CVCi). Cerebrovascular reactivity was calculated as the change in cerebral blood velocity or CVCi over the change in end-tidal CO 2 . Aortic arch stiffness, as pulse wave velocity (aaPWV), was calculated from ultrasound scans of the aortic valve and the descending aorta. Differences between groups were assessed with Mann-Whitney tests. Results: Eleven women were recruited (5 controls and 6 cancer survivors who had received treatment). Cancer types included melanoma, lymphoma, and breast cancer. Age and resting MAP were similar between groups. Mx values were higher in cancer survivors (-0.13 ± 0.14 vs. 0.14 ± 0.11, p < 0.05). Cerebrovascular reactivity, both absolute (2.8 ± 1.1 vs. 1.6 ± 0.8, p = 0.05) and as CVCi (16.8 ± 2.4 vs. 2.3 ± 9.4, p < 0.05), were lower in cancer survivors. aaPWV was higher in cancer survivors (2.7 ± 0.8 vs. 3.8 ± 0.6, p < 0.05). Across the entire study sample, aaPWV trended towards an association only with absolute cerebrovascular reactivity (Spearman r = -0.6, p = 0.054). Conclusion: Aortic stiffness was elevated and both cerebrovascular regulatory functions were impaired in cancer survivors compared to healthy controls. Present findings highlight the importance of monitoring cerebral and global vascular function in cancer survivors at high-risk for cognitive decline.