Wyller Vegard Bruun, Saul J Philip, Walløe Lars, Thaulow Erik
Department of Pediatrics, Rikshospitalet-Radiumhospitalet Medical Center, 0027 Oslo, Norway.
Eur J Appl Physiol. 2008 Apr;102(6):623-32. doi: 10.1007/s00421-007-0634-1. Epub 2007 Dec 8.
The chronic fatigue syndrome (CFS) has been shown to be associated with orthostatic intolerance and cardiovascular dysregulation. We investigated the cardiovascular responses to combined orthostatic stress and isometric exercise in adolescents with CFS. We included a consecutive sample of 15 adolescents 12-18 years old with CFS diagnosed according to a thorough and standardized set of investigations, and a volunteer sample of 56 healthy control subjects of equal sex and age distribution. Heart rate, systolic, mean and diastolic blood pressure, stroke index, and total peripheral resistance index were non-invasively recorded during lower body negative pressure (LBNP) combined with two consecutive periods of handgrip. In addition, we measured baseline plasma catecholamines, and recorded symptoms. At rest, CFS patients had higher heart rate, diastolic blood pressure, plasma norepinephrine (P < 0.01), mean blood pressure and plasma epinephrine (P < 0.05) than controls. During LBNP, CFS patients had a greater increase in heart rate, diastolic blood pressure, mean blood pressure (P < 0.05) and total peripheral resistance index (n.s.) than controls. During handgrip, CFS patients had a smaller increase in heart rate, diastolic blood pressure (P < 0.05), mean blood pressure and total peripheral resistance index (n.s.) than controls. Our results indicate that adolescents with CFS have increased sympathetic activity at rest with exaggerated cardiovascular response to orthostatic stress, but attenuated cardiovascular response when performing isometric exercise during orthostatic stress. This suggests that CFS might be causally related to sympathetic dysfunction.
慢性疲劳综合征（CFS）已被证明与直立不耐受和心血管调节异常有关。我们研究了患有CFS的青少年在直立应激和等长运动联合作用下的心血管反应。我们纳入了15名年龄在12至18岁之间、根据一套全面且标准化的检查被诊断为CFS的青少年连续样本，以及56名性别和年龄分布相同的健康对照志愿者样本。在下肢负压（LBNP）联合连续两个阶段的握力运动过程中，无创记录心率、收缩压、平均压和舒张压、心搏指数以及总外周阻力指数。此外，我们测量了基线血浆儿茶酚胺，并记录了症状。静息时，CFS患者的心率、舒张压、血浆去甲肾上腺素（P < 0.01）、平均血压和血浆肾上腺素（P < 0.05）均高于对照组。在LBNP期间，CFS患者的心率、舒张压、平均血压（P < 0.05）和总外周阻力指数（无显著差异）的升高幅度均大于对照组。在握力运动期间，CFS患者的心率、舒张压（P < 0.05）、平均血压和总外周阻力指数的升高幅度均小于对照组。我们的结果表明，患有CFS的青少年在静息时交感神经活动增强，对直立应激的心血管反应过度，但在直立应激期间进行等长运动时心血管反应减弱。这表明CFS可能与交感神经功能障碍存在因果关系。
