LAUSR

Introduction: Aging is associated with arterial stiffening which increases pressure reflection to the heart and contributes to the development of cardiovascular disease. However, most vascular aging studies have focused on comparing young adults versus adults 65 or older, and comorbidities, such as hypertension and obesity, confounded the findings. The extent of vascular aging in healthy mid-life adults (age 50-64) is unclear. Therefore, the purpose of this study was to compare arterial stiffness and wave reflection in healthy young adults (18-35 years) and healthy mid-life adults. Methods: Twenty-six apparently healthy, nonsmoking, adults underwent assessments of arterial stiffness and wave reflection. Young adults (YA; n=15, 6 eumenorrheic women; age: 28±4 yr; systolic blood pressure [SBP]: 109±8 mmHg; body mass index [BMI]: 24.1±2.5 kg/m2; mean±SD) were compared to mid-life adults (MA; n=11, 8 postmenopausal women; age: 59±4 yr; SBP: 109±10 mmHg; BMI: 25.6±4.1 kg/m2). Using SphygmoCor XCEL (AtCor Medical), aortic arterial stiffness was measured as carotid to femoral pulse wave velocity (cfPWV) and wave reflection was measured as augmentation index normalized at heart rate of 75 (Alx75), augmented pressure (AP), backward wave pressure (Pb), and reflection magnitude (RM). Results: No significant differences between YA and MA were found in brachial and aortic SBP, diastolic blood pressure, and pulse pressure (P≥0.07). Compared to YA, MA had higher cfPWV (MA vs. YA: 6.8±0.9 m/s vs. 5.8±0.6 m/s, p=0.001), Alx75 (30±10% vs. 4±10%, p<0.001), AP (13±4 mmHg vs. 4±3 mmHg, p<0.001), Pb (16±2 mmHg vs. 13±2 mmHg, p=0.001), and RM (67.7±6.8% vs. 48.0±5.6%, p<0.001). Conclusions: Our findings suggest that mid-life adults exhibit increased arterial stiffness and wave reflection compared to young adults. These data suggest that vascular aging may already be present in mid-life adults, despite normal peripheral blood pressure. These findings help extend our understanding of the sequence of age-related changes in vascular function throughout the lifespan. This work was supported by NIAAA K99/R00 AA028537 to CLH. This is the full abstract presented at the American Physiology Summit 2023 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.