Endothelial dysfunction in postmenopausal females with previous or current vasomotor symptoms

Introduction: Postmenopausal females with a history of vasomotor symptoms (VMS; hot flushes and night sweats) exhibit an increased prevalence of hypertension and cardiovascular disease (CVD) compared to those without VMS. Endothelial dysfunction, an early predictor of atherosclerosis, may be an important mechanistic driver of this relationship. Lower reactive hyperemia (RHI), measured by the Endothelial Peripheral Arterial Tone (EndoPAT) device, has been associated with an increase in CVD events. The purpose of this study was to test the hypothesis that postmenopausal females with current or previous VMS demonstrate greater endothelial dysfunction when compared with postmenopausal females who have never experienced VMS. Methods: Twenty-nine postmenopausal females completed two study visits. Visit 1: Informed consent; medical questionnaire; Menopause-Specific Quality of Life Questionnaire (MENQOL); and the Pittsburgh Sleep Quality Index (PSQI). Participants were divided into two groups based on whether they had ever experienced hot flushes (ever-flushers: EF, n=16) or never experienced hot flushes (never-flushers: NF, n=13). Visit 2: Heart rate (HR; electrocardiography) and blood pressure (BP; finger plethysmography) were recorded during a 10-min rest. Endothelial function was measured via an EndoPAT device and quantified using a RHI and the natural logarithm of the RHI (LnRHI). A blood draw was completed and the plasma levels of estrone, estradiol, follicle-stimulating hormone (FSH) and testosterone were analyzed. Comparisons between ever-flushers and never-flushers were completed using independent sample t-tests. Results: Never-flushers did not experience VMS (1±0a.u, Ẋ±SD), as confirmed by the MENQOL, while EF who were currently experiencing VMS presented with moderate symptoms (n=11, 4±1 out of 8a.u., 8 being the most severe, p>0.01). There were no differences between the groups in age (NF: 60±4; EF: 60±4yrs, p=0.98), age of menopause (NF: 49±4; EF: 51±4yrs, p=0.22), body mass index (NF: 25±4; EF: 27±4kg/m 2 , p=0.36), PSQI sleep scores (NF: 6±3; EF: 7±3a.u., p=0.36), and levels of estrone (NF: 31±27; EF: 20±7pg/mL, p=0.17), estradiol (NF: 6±6; EF: 4±2pg/mL, p=0.29), FSH (NF: 92±25; EF: 75±22IU/L, p=0.15) and testosterone (NF: 22±12; EF: 18±5ng/dL, p=0.21). The groups also had similar resting systolic BP (NF: 127±14; EF: 120±6mmHg, p=0.13), diastolic BP (NF: 80±12; EF: 78±8mmHg, p=0.71) and HR (NF: 61±7; EF: 60±5bpm, p=0.38). Ever-flushers, however, exhibited a reduced RHI (EF: 1.9±0.4a.u.) and LnRHI (EF: 0.6±0.2a.u.) compared to NFs (RHI: 2.3±0.6a.u.; p=0.03; LnRHI: 0.8±0.2a.u.; p=0.02). Conclusion: We observed a lower RHI and LnRHI in the ever-flusher group compared to the never-flusher group, suggesting that individuals who previously have or currently experience VMS demonstrate impaired endothelial function, before changes in BP may emerge. This impairment may contribute to the development of hypertension and the increased risk of CVD observed with individuals experiencing menopausal hot flushes. NIH 1 K01 AG064038-01A1, NIH R21 AG80503-01A1 (MLKR), UMN Grant-in-Aid and NIH National Center for Advancing Translational Sciences, grant UL1TR002494. 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.