Department of Kinesiology, McMaster University , Hamilton, Ontario , Canada.
Am J Physiol Heart Circ Physiol. 2018 Aug 1;315(2):H357-H365. doi: 10.1152/ajpheart.00039.2018. Epub 2018 Apr 20.
Arterial stiffness is associated with increased cardiovascular disease risk. Previous sex-based investigations of local and central stiffness report inconsistent findings and have not controlled for menstrual cycle phase in women. There is also evidence that sex hormones influence the vasculature, but their impact on arterial stiffness across a natural menstrual (NAT) or oral contraceptive pill (OCP) cycle has been understudied. This study sought to 1) examine potential sex differences in local and central stiffness, 2) compare stiffness profiles between NAT and OCP cycles, and 3) investigate the relationship between duration of OCP use and arterial stiffness. Sex hormone concentrations, β-stiffness index (local stiffness), and carotid-femoral pulse wave velocity [cfPWV (central stiffness)] were assessed in 53 healthy adults (22 ± 3 yr old, 20 men, 15 NAT women, and 18 OCP women). All participants were tested three times: men on the same day and time 1 wk apart, NAT women in menstrual, midfollicular and luteal phases of the menstrual cycle, and OCP women in placebo, early active and late active pill phases. β-Stiffness was higher in men than NAT and OCP women ( P < 0.001), whereas cfPWV was similar between groups ( P = 0.09). β-Stiffness and cfPWV did not differ across or between NAT and OCP cycles ( P > 0.05 for both) and were not associated with duration of OCP use (β-stiffness: r = 0.003, P = 0.99; cfPWV: r = -0.26, P = 0.30). The apparent sex differences in local, but not central, stiffness highlight the importance of assessing both indexes in comparisons between men and women. Furthermore, fluctuating sex hormone levels do not appear to influence β-stiffness or cfPWV. Therefore, these stiffness indexes may need to be assessed during only one cycle phase in women in future investigations. NEW & NOTEWORTHY We observed higher local, but not central, arterial stiffness in men than women. We also demonstrated that there are no differences in arterial stiffness between naturally cycling women and women who use monophasic oral contraceptive pills, and that the duration of oral contraceptive pill use does not influence arterial stiffness.
动脉僵硬度与心血管疾病风险增加有关。之前基于性别的局部和中央僵硬度研究报告结果不一致，并且没有在女性中控制月经周期阶段。有证据表明性激素会影响血管，但它们对自然月经（NAT）或口服避孕药（OCP）周期中动脉僵硬度的影响研究较少。本研究旨在：1）检查局部和中央僵硬度的潜在性别差异，2）比较 NAT 和 OCP 周期之间的僵硬度曲线，3）研究 OCP 使用时间与动脉僵硬度的关系。评估了 53 名健康成年人（22±3 岁，20 名男性，15 名自然周期女性和 18 名口服避孕药女性）的性激素浓度、β-僵硬度指数（局部僵硬度）和颈股脉搏波速度[cfPWV（中央僵硬度）]。所有参与者均接受了 3 次测试：男性在相隔 1 周的同一天和时间接受测试，自然周期女性在月经周期的卵泡期、中期和黄体期接受测试，口服避孕药女性在安慰剂、早期活性和晚期活性药物阶段接受测试。β-僵硬度男性高于自然周期和口服避孕药女性（P<0.001），而组间 cfPWV 相似（P=0.09）。NAT 和 OCP 周期之间或之间的β-僵硬度和 cfPWV 没有差异（两者 P>0.05），并且与 OCP 使用时间无关（β-僵硬度：r=0.003，P=0.99；cfPWV：r=-0.26，P=0.30）。局部僵硬度存在明显的性别差异，但中央僵硬度没有差异，这突出了在男性和女性之间进行比较时评估这两个指标的重要性。此外，性激素水平的波动似乎不会影响β-僵硬度或 cfPWV。因此，在未来的研究中，女性可能只需要在一个周期阶段评估这些僵硬度指标。
