Ongoing, Chronic Stress Exposure Is Related to Impaired Vascular Endothelial Function Among Young Adults Irrespective of Subjective Appraisal of Stressor Severity

Abstract

Introduction: Chronic stress is associated with cardiovascular morbidity independently of traditional cardiovascular risk factors. Vascular endothelial function (VEF) is predictive of cardiovascular risk and is reduced in response to transient and chronic psychosocial stress. While dominant stress theories (i.e., differential exposure model) posit that stress exposure explains health disparities, it has also been hypothesized that the subjective experience of these stressors — or stress appraisal — may also influence the effects of stress exposure on health. The purpose of this study was to investigate the associations of ongoing, chronic stress exposure and stress appraisal on VEF in young adults. Our hypothesis was that ongoing, chronic stress exposure, rather than stress appraisal, would be more strongly and inversely associated with VEF. We further conceptualized that stress appraisal would moderate the association between stress exposure and VEF. Methods: In 64, healthy young adults (75% Female; age = 25 ± 5 y), we assessed cumulative, chronic stress exposure with a measure that quantified ongoing exposure to 8 specific stressors over the last 12 months. For each chronic stress exposure reported, participants rated the perceived stressor severity using a 3-point Likert scale ( 1 = not upsetting, 2 = somewhat upsetting, 3 = very upsetting). The number of stressors was used as the indicator of ongoing, chronic stress exposure, while the average stressor severity was used as the indicator of stress appraisal. We assessed VEF using the brachial artery flow mediated dilation (FMD) technique normalized to the shear rate stimulus (%·[s1×10−2]) quantified as shear rate area under the curve. Using partial correlations, we examined relations among ongoing, chronic stress exposure and stress appraisal versus VEF, independently of sex. We then conducted an exploratory moderation analysis to assess whether stress appraisal moderated the effect of ongoing, chronic stress exposure on VEF. Results: Ongoing, chronic stress exposure (r=-0.32, p<0.05), but not stress appraisal (r=-0.13, p=0.34) was related to VEF. Further, stress appraisal did not significantly moderate the association between ongoing, chronic stress exposure and VEF (p=0.69). However, the direct effect of ongoing, chronic stress exposure was statistically significant (β = -0.51; p=0.009), whereas the effect of stress appraisal was not (p=0.79), confirming our initial correlation analyses. Conclusions: Our findings indicate that ongoing, chronic stress exposure, rather than the subjective appraisal of this stress, significantly predicts impaired vascular endothelial function among young adults. Thus, our findings provide initial evidence indicating that stressor exposure is suffcient to increase cardiovascular risk independently of the perceived severity of the stressor(s) among young adults. However, the strength of our moderation analysis is limited by sample size, and future larger-scale studies may be necessary to fully understand the degree to which stress appraisal moderates the link between chronic stress and cardiovascular risk. Future studies may also seek to understand how potentially important, modifiable psychological processes influence this relationship, which may also be independent of stress appraisal. Funding provided by a grant from the Injury Prevention Research Center through the CDC (R49 CE003095; NDMJ and EBKT). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.