Jiang Xin, Guo Yi, Zhao Yue, Gao Xia, Peng Dan, Zhang Hui, Deng Wuhong, Fu Wen, Qin Na, Chang Ruizhen, Manor Brad, Lipsitz Lewis A, Zhou Junhong
Department of Geriatrics, Shenzhen People's Hospital, Shenzhen, China.
The Second Clinical Medical College, Jinan University, Shenzhen, China.
Front Cardiovasc Med. 2021 Feb 26;8:636702. doi: 10.3389/fcvm.2021.636702. eCollection 2021.
White matter lesions (WMLs) are highly prevalent in older adults, and hypertension is one of the main contributors to WMLs. The blood pressure (BP) is regulated by complex underlying mechanisms over multiple time scales, thus the continuous beat-to-beat BP fluctuation is complex. The association between WMLs and hypertension may be manifested as diminished complexity of BP fluctuations. The aim of this pilot study is to explore the relationships between hypertension, BP complexity, and WMLs in older adults. Fifty-three older adults with clinically diagnosed hypertension and 47 age-matched older adults without hypertension completed one MRI scan and one BP recording of 10-15 min when sitting quietly. Their cerebral WMLs were assessed by two neurologists using the Fazekas scale based on brain structural MRI of each of their own. Greater score reflected higher WML grade. The complexity of continuous systolic (SBP) and diastolic (DBP) BP series was quantified using multiscale entropy (MSE). Lower MSE reflected lower complexity. Compared to the non-hypertensive group, hypertensives had significantly greater Fazekas scores ( > 5.3, < 0.02) and lower SBP and DBP complexity ( > 8.6, < 0.004). Both within each group (β < -0.42, < 0.01) and across groups (β < -0.47, < 0.003), those with lower BP complexity had higher Fazekas score. Moreover, complexity of both SBP and DBP mediated the influence of hypertension on WMLs (indirect effects > 0.25, 95% confidence intervals = 0.06 - 0.50). These results suggest that diminished BP complexity is associated with WMLs and may mediate the influence of hypertension on WMLs. Future longitudinal studies are needed to examine the causal relationship between BP complexity and WMLs.
白质病变（WMLs）在老年人中非常普遍，高血压是导致WMLs的主要因素之一。血压（BP）受多种时间尺度下复杂的潜在机制调节，因此连续的逐搏血压波动很复杂。WMLs与高血压之间的关联可能表现为血压波动复杂性降低。这项初步研究的目的是探讨老年人高血压、血压复杂性和WMLs之间的关系。53名临床诊断为高血压的老年人和47名年龄匹配的非高血压老年人在安静坐着时完成了一次10 - 15分钟的MRI扫描和一次血压记录。两名神经科医生根据他们各自的脑结构MRI，使用Fazekas量表评估他们的脑WMLs。分数越高反映WML等级越高。使用多尺度熵（MSE）对连续收缩压（SBP）和舒张压（DBP）血压序列的复杂性进行量化。较低的MSE反映较低的复杂性。与非高血压组相比，高血压患者的Fazekas评分显著更高（>5.3，<0.02），SBP和DBP复杂性更低（>8.6，<0.004）。在每组内部（β<-0.42，<0.01）以及两组之间（β<-0.47，<0.003），血压复杂性较低的人Fazekas评分更高。此外，SBP和DBP的复杂性都介导了高血压对WMLs的影响（间接效应>0.25，95%置信区间=0.06 - 0.50）。这些结果表明，血压复杂性降低与WMLs相关，并且可能介导高血压对WMLs的影响。未来需要进行纵向研究来检验血压复杂性与WMLs之间的因果关系。
