Department of Health and Human Development, Montana State University, Bozeman, Montana.
Department of Psychology, Montana State University, Bozeman, Montana.
J Appl Physiol (1985). 2021 Feb 1;130(2):491-497. doi: 10.1152/japplphysiol.00825.2020. Epub 2020 Dec 10.
K-complexes are a key marker of nonrapid eye movement sleep, specifically during stages II sleep. Recent evidence suggests the heart rate responses to a K-complexes may differ between men and women. The purpose of this study was to compare beat-to-beat blood pressure responses to K-complexes in men and women. We hypothesized that the pressor response following a spontaneous K-complex would be augmented in men compared with women. Ten men [age: 23 ± 2 yr, body mass index (BMI): 28 ± 4 kg/m] and ten women (age: 23 ± 5 yr, BMI: 25 ± 4 kg/m) were equipped with overnight finger plethysmography and standard 10-lead polysomnography. Hemodynamic responses to a spontaneous K-complex during stable stage II sleep were quantified for 10 consecutive cardiac cycles, and measurements included systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and heart rate. K-complex elicited greater pressor responses in men when blood pressures were expressed as SAP (cardiac cycle × sex: = 0.007) and DAP (cardiac cycle × sex: = 0.004). Heart rate trended to be different between men and women (cardiac cycle × sex: = 0.078). These findings suggest a divergent pressor response between men and women following a spontaneous K-complex during normal stage II sleep. These findings could contribute to sex-specific differences in cardiovascular risk that exist between men and women. K-complexes during stage II sleep have been shown to elicit acute increases in blood pressure and heart rate, but the role of sex (i.e., male vs. female) in this response is unclear. In the present study, we demonstrate that the pressor response following spontaneous K-complexes were augmented in men compared to age-matched women. The augmented blood pressure reactivity to spontaneous K-complexes during stage II sleep in men advance the field of cardiovascular sex differences, with implications for nocturnal blood pressure control.
K 复合波是非快速眼动睡眠的一个关键标志物，特别是在睡眠的第二阶段。最近的证据表明，心率对 K 复合波的反应在男性和女性之间可能不同。本研究的目的是比较男性和女性的 K 复合波对逐搏血压的反应。我们假设自发性 K 复合波后血压的加压反应在男性中会比女性增强。10 名男性（年龄：23 ± 2 岁，体重指数（BMI）：28 ± 4 kg/m）和 10 名女性（年龄：23 ± 5 岁，BMI：25 ± 4 kg/m）配备了夜间手指容积描记法和标准的 10 导多导睡眠图。在稳定的第二阶段睡眠期间，对自发性 K 复合波的血流动力学反应进行了 10 个连续心动周期的量化，并测量了收缩压（SAP）、舒张压（DAP）和心率。当血压表示为 SAP（心动周期×性别： = 0.007）和 DAP（心动周期×性别： = 0.004）时，K 复合波在男性中引起更大的加压反应。心率在男性和女性之间也存在差异（心动周期×性别： = 0.078）。这些发现表明，在正常的第二阶段睡眠期间，自发性 K 复合波后男性和女性的加压反应不同。这些发现可能导致男性和女性之间存在心血管风险的性别特异性差异。第二阶段睡眠期间的 K 复合波已被证明会引起血压和心率的急性升高，但性别（即男性与女性）在这种反应中的作用尚不清楚。在本研究中，我们证明自发性 K 复合波后男性的加压反应比年龄匹配的女性增强。男性在第二阶段睡眠期间自发 K 复合波后的血压反应增强，推进了心血管性别差异领域的发展，对夜间血压控制具有重要意义。
