Department of Kinesiology and Community Health, College of Applied Health Science, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Department of Kinesiology, California State University, Dominguez Hills, Carson, CA 90747, USA.
Int J Environ Res Public Health. 2021 Dec 21;19(1):47. doi: 10.3390/ijerph19010047.
Hypertension is considered a risk factor for cardiovascular health and non-amnestic cognitive impairment in older adults. While heart rate reserve (HRR) has been shown to be a risk factor for hypertension, how impaired HRR in older adults can lead to cognitive impairment is still unclear. The objective of this study was to examine the effects of HRR on prefrontal cortical (PFC) activation under varying dual-task demands in older adults. Twenty-eight older adults (50-82 years of age) were included in this study and divided into higher ( = 14) and lower ( = 14) HRR groups. Participants engaged in the cognitive task which was the Modified Stroop Color Word Test (MSCWT) on a self-paced treadmill while walking. Participants with higher HRR demonstrated increased PFC activation in comparison to lower HRR, even after controlling for covariates in analysis. Furthermore, as cognitive task difficulty increased (from neutral to congruent to incongruent to switching), PFC activation increased. In addition, there was a significant interaction between tasks and HRR group, with older adults with higher HRR demonstrating increases in PFC activation, faster gait speed, and increased accuracy, relative to those with lower HRR, when going from neutral to switching tasks. These results provide evidence of a relationship between HRR and prefrontal cortical activation and cognitive and physical performance, suggesting that HRR may serve as a biomarker for cognitive health of an older adult with or without cardiovascular risk.
高血压被认为是心血管健康和老年人非遗忘性认知障碍的一个危险因素。虽然心率储备（HRR）已被证明是高血压的一个危险因素，但老年人 HRR 受损如何导致认知障碍仍不清楚。本研究的目的是探讨 HRR 在老年人不同双重任务需求下对前额叶皮质（PFC）激活的影响。本研究纳入了 28 名老年人（50-82 岁），并将其分为高 HRR 组（n=14）和低 HRR 组（n=14）。参与者在自我调节跑步机上进行认知任务，即改良斯特鲁普颜色-词测试（MSCWT）的同时行走。与低 HRR 组相比，高 HRR 组的参与者在分析中控制了协变量后，表现出更高的 PFC 激活。此外，随着认知任务难度的增加（从中性到一致到不一致再到转换），PFC 激活增加。此外，任务和 HRR 组之间存在显著的交互作用，与低 HRR 组相比，高 HRR 组的老年人在从中性任务转换为转换任务时，PFC 激活增加，步速加快，准确性提高。这些结果提供了 HRR 与前额叶皮质激活以及认知和身体表现之间关系的证据，表明 HRR 可能是有或无心血管风险的老年人认知健康的生物标志物。
