Fitness and Blood Pressure are Associated with Vascular Responses to a High-Fat Meal in Middle-Aged Women

Background: The midlife period in women coincides with the menopausal transition and represents a critical paradigm shift in which cardiovascular disease (CVD) risk accelerates. A physiological stressor such as a high-fat meal (HFM) impairs vascular function, providing an insight into potential CVD risk. Regular physical activity and higher aerobic fitness are beneficial for vascular health. However, there is limited data on vascular responses to a HFM across menopause and the potential protective role of fitness. Objective: To evaluate vascular responses to HFM across menopause stages and the association of aerobic fitness in a sample of middle-aged women. Hypothesis: The magnitude of impairment invascular function following HFM consumption will increase across menopause stages; however, impairments in post-HFM vascular function will be attenuated in women with higher aerobic fitness. Methods: Macrovascular function via brachial artery flow-mediated dilation (%FMD, defined as [(peak post-occlusion diameter – baseline diameter)/baseline diameter]*100) before and following a standard, liquid HFM (~84% calories from fat) was assessed in a sample of36 healthy, middle-aged women (49 ± 6 y) who were premenopausal (PRE, N = 15), perimenopausal (PERI, N = 10), and postmenopausal (POST, N = 11). %FMD was measured at baseline (BL), one (1HP), and two (2HP) hours after the ingestion of the HFM. Aerobic fitness was evaluated from predicted VO2max using a submaximal VO2 test on a cycle ergometer and blood pressure was measured using oscillometry. Results: BL %FMD was significantly lower in POST (3.09 ± 1.89) than in PRE (5.68 ± 2.42, p = 0.01) and in PERI (5.39 ± 2.20, p = 0.02). Vascular responses (Δ%FMD) to the HFM were similar (p = 0.85) between PRE, PERI, and POST at both 1HP (-0.33 ± 2.37, 0.046 ± 1.61, -0.73 ± 2.57, respectively) and 2HP (1.07 ± 1.92, 0.62 ± 2.01, 0.81 ± 1.79, respectively). Higher aerobic fitness was modestly correlated (r = 0.40, p = 0.045) with increases in FMD in response to HFM (2HP), whereas higher diastolic blood pressure was moderately correlated (r = -0.43, p = 0.01) with decreased FMD in response to HFM (2HP). Conclusion: Pre-, peri-, and post-menopausal women respond similarly to a HFM across middle age; however, women with higher blood pressure may be more susceptible to postprandial vascular impairment. Conversely, aerobic fitness may play a vascular protective role against physiological stressors during this critical transition period, highlighting the importance of promoting healthy lifestyle behaviors in this age group. Funding source: University of Maryland Graduate School Faculty Student Research Award (Ranadive, Blake) This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.