Department of Clinical Neurological Sciences, University Hospital, London Health Sciences Centre, London, Ontario, Canada.
J Appl Physiol (1985). 2013 Aug 15;115(4):525-8. doi: 10.1152/japplphysiol.00292.2013. Epub 2013 Jun 13.
Reports have shown that younger individuals present with higher postural heart rate increments on head-up tilt (HUT). However, a correlation between the degree of heart rate increment and symptoms of orthostatic intolerance has not been determined. The objective of this study was to determine whether higher postural heart rate increments during HUT correlate with symptoms of orthostatic intolerance in healthy subjects. Postural heart rate increment on HUT did not differ between men and women (P = 0.48) but did show a significant decrease by age group (P < 0.0001). There was a significant negative correlation between heart rate increment on HUT and age [r = -0.63 (-0.73, -0.51), r(2) = 0.400; P < 0.0001]. There was a significant difference with respect to symptoms of orthostatic intolerance by sex (P = 0.03) but not age (P = 0.58). There was no significant correlation between either symptoms of orthostatic intolerance and age [r = -0.13 (-0.31, 0.06), r(2) = 0.017; P = 0.17] or heart rate increment on HUT and symptoms of orthostatic intolerance [r = 0.15 (-0.04, 0.33), r(2) = 0.022; P = 0.13]. The results demonstrate that higher postural heart rate increments in younger individuals do not result in an increase in orthostatic intolerance. This highlights the potential need for a reevaluation of the diagnostic criteria for postural orthostatic tachycardia syndrome in younger individuals.
报告显示，年轻个体在头高位倾斜（HUT）时表现出更高的体位心率增量。然而，心率增量的程度与直立不耐受症状之间的相关性尚未确定。本研究的目的是确定 HUT 期间较高的体位心率增量是否与健康受试者的直立不耐受症状相关。HUT 期间的体位心率增量在男性和女性之间没有差异（P = 0.48），但按年龄组显示出显著下降（P < 0.0001）。HUT 上的心率增量与年龄之间存在显著负相关[r = -0.63（-0.73，-0.51），r² = 0.400；P < 0.0001]。性别方面，直立不耐受症状存在显著差异（P = 0.03），但年龄方面没有差异（P = 0.58）。直立不耐受症状与年龄之间没有显著相关性[r = -0.13（-0.31，0.06），r² = 0.017；P = 0.17]，HUT 上的心率增量与直立不耐受症状之间也没有显著相关性[r = 0.15（-0.04，0.33），r² = 0.022；P = 0.13]。结果表明，年轻个体中较高的体位心率增量不会导致直立不耐受增加。这突出表明，需要重新评估年轻个体体位性心动过速综合征的诊断标准。
