Menopausal Hot Flashes Are Not Associated with Pressor Responses to Cold Stress

Abstract

Menopausal females who experience frequent hot flashes (episodes of increased body temperature and sweating) have a greater risk of hypertension and cardiovascular disease than females without hot flashes. Individuals with exaggerated blood pressure (BP) responses to cold stress have a higher risk of hypertension than those with lower responses. It is unknown if females who experience hot flashes have exaggerated pressor responses to cold stress, indicating their greater risk of hypertension. The aim of this study was to determine the pressor responses to cold stress in females who experience hot flashes and those who do not. An additional goal was to understand the relation between daily hot flash frequency and pressor responses. We hypothesized that females with hot flashes would have exaggerated pressor responses to cold stress compared to females without hot flashes. We also hypothesized that pressor responses would be positively correlated to daily hot flash frequency. We recruited 17 females, ages 45-60 years, without hypertension or cardiovascular disease, who did and did not have hot flashes. They reported hot flash frequency in a 3-day written diary. On the study day, continuous BP (finger photoplethysmography, calibrated to brachial cuff BP) and heart rate (HR; 3-lead ECG) were recorded while the participant rested during a 2-minute baseline period, then subsequently had an ice-water pack placed on their forehead for 3 minutes. The changes in mean BP (MBP) and HR are calculated as the change in MBP or HR during the cold pressor test minus the average MBP or HR during baseline. Data were analyzed using the Student’s t-test and Pearson correlation. Twelve females reported hot flashes (age: 51±4 years; average number of hot flashes: 3 per day) and five did not (age: 49±5 years). These groups did not differ in age, body mass index, resting MBP, or resting HR (p>0.05 for all). The change in MBP from baseline to the cold pressor test did not differ between females with and without hot flashes (Δ17±10 vs. Δ19±14 mmHg, respectively; p=0.860). The change in HR with the cold pressor test also did not differ between females who did and did not report hot flashes (Δ10±6 vs. Δ12±8 mmHg, respectively; p=0.647). In females with hot flashes, the number of hot flashes reported per day (range: 1-12 per day) was not correlated with the change in MBP (p=0.824) or HR (p=0.460) during the cold pressor test. These current data show that menopausal females who experience hot flashes do not exhibit exaggerated BP or HR responses to cold stress in comparison to females who do not experience hot flashes. In addition, BP and HR responses are not correlated with daily hot flash frequency. There are likely other vascular mechanisms that place menopausal females with hot flashes at an increased risk for hypertension. In addition, incorporating information on the age at which hot flashes began, as well as hot flash severity, might help us to further understand cardiovascular risk in this population. AHA 898649, NIH T32 DK07352, K01 HL148144, NCATS UL1 TR002377. 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.