Duschek Stefan, Hoffmann Alexandra, Reyes Del Paso Gustavo A, Ettinger Ulrich
Institute of Psychology, UMIT-University of Health Sciences Medical informatics and Technology, Eduard Wallnöfer-Zentrum 1, 6060, Hall in Tirol, Austria.
Institute of Psychology, University of Jaén, Jaén, Spain.
Ann Behav Med. 2017 Jun;51(3):442-453. doi: 10.1007/s12160-016-9868-7.
Chronic low blood pressure (hypotension) is characterized by complaints such as fatigue, reduced drive, dizziness, and cold limbs. Additionally, deficits in attention and memory have been observed. Autonomic dysregulation is considered to be involved in the origin of this condition.
The study explored autonomic cardiovascular control in the context of higher cognitive processing (executive function) in hypotension.
Hemodynamic recordings were performed in 40 hypotensive and 40 normotensive participants during execution of four classical executive function tasks (number-letter task, n-back task, continuous performance test, and flanker task). Parameters of cardiac sympathetic control, i.e., stroke volume, cardiac output, pre-ejection period, total peripheral resistance, and parasympathetic control, i.e., respiratory sinus arrhythmia and baroreflex sensitivity, were obtained.
The hypotensive group exhibited lower stroke volume and cardiac output, as well as higher pre-ejection period and baroreflex sensitivity during task execution. Increased error rates in hypotensive individuals were observed in the n-back and flanker tasks. In the total sample, there were positive correlations of error rates with pre-ejection period, baroreflex sensitivity and respiratory sinus arrhythmia, and negative correlations with cardiac output.
Group differences in stroke volume, cardiac output, and pre-ejection period suggest diminished beta-adrenergic myocardial drive during executive function processing in hypotension, in addition to increased baroreflex function. Although further research is warranted to quantify the extent of executive function impairment in hypotension, the results from correlation analysis add evidence to the notion that higher sympathetic inotropic influences and reduced parasympathetic cardiac influences are accompanied by better cognitive performance.
慢性低血压的特征包括疲劳、动力下降、头晕和四肢发冷等症状。此外，还观察到注意力和记忆力方面的缺陷。自主神经调节功能紊乱被认为与这种情况的发生有关。
本研究探讨了低血压患者在更高层次认知加工（执行功能）背景下的自主心血管控制情况。
对40名低血压参与者和40名血压正常的参与者在执行四项经典执行功能任务（数字-字母任务、n-back任务、连续性能测试和侧翼任务）期间进行血流动力学记录。获取心脏交感神经控制参数，即每搏输出量、心输出量、射血前期、总外周阻力，以及副交感神经控制参数，即呼吸性窦性心律不齐和压力反射敏感性。
低血压组在任务执行期间每搏输出量和心输出量较低，射血前期和压力反射敏感性较高。在n-back任务和侧翼任务中观察到低血压个体的错误率增加。在整个样本中，错误率与射血前期、压力反射敏感性和呼吸性窦性心律不齐呈正相关，与心输出量呈负相关。
每搏输出量、心输出量和射血前期的组间差异表明，除压力反射功能增强外，低血压患者在执行功能加工过程中β-肾上腺素能心肌驱动减弱。尽管有必要进一步研究以量化低血压患者执行功能损害的程度，但相关性分析结果为以下观点提供了证据，即更高的交感正性肌力影响和降低的副交感神经对心脏的影响伴随着更好的认知表现。
