Abstract:

Objective To investigate the correlation between diurnal fluctuation of blood pressure and  intracranial atherosclerotic plaque characteristics, including the atherosclerotic plaque burden and its vulnerability. 

Methods The clinical and imaging data of 267 stroke patients from an intracranial atherosclerotic stroke imaging cohort were included in this retrospective analysis. According to 24-hour ambulatory blood pressure fluctuation rhythm, the patients were divided as dipper, nondipper, and reverse-dipper groups. High resolution MR vessel wall imaging was used to evaluate atherosclerotic plaque burden and its vulnerability. The intracranial atherosclerotic plaque characteristics including maximum vessel wall thickness (maxWT), intraplaque hemorrhage (IPH), moderate-severe stenosis (≥50%), multiple plaques (≥3 plaques) and etc. Baseline characteristics and plaque characteristics were compared among three groups, and multivariate logistic regression analysis was used to determine the association between diurnal fluctuation pattern of blood pressure and intracranial plaque burden and vulnerability. 

Results There were 36, 119 and 112 patients in the dipper, non-dipper, and reverse-dipper groups, respectively. (1) The age was the eldest (the mean age: 67.3, 64.6, and 61.9 years old in reversedipper, non-dipper and dipper groups, respectively, P=0.042), the proportion of diabetes was the highest (46.4%, 41.2%, and 22.2% in reverse-dipper, non-dipper and dipper groups, respectively, P=0.037), and the mean 24-hour systolic blood pressure was the highest (144 mmHg in reversedipper group, 139 mmHg in non-dipper group, and 136 mmHg in dipper groups, respectively, P=0.025) in the reverse-dipper group among the three groups; (2) The plaque characteristics in dipper, non-dipper, and reverse-dipper groups were as follows: the maxWT was 2.39 mm, 2.48 mm and 2.52 mm, P=0.554; the prevalence of IPH was 33.3% (12/36), 36.1% (43/119) and 37.5% (42/112), P=0.901; the proportion of moderate-severe stenosis of large intracranial artery was 22.2%, 32.8%, and 37.5%, P=0.236, and the proportion of multiple plaques was 63.9%, 73.9%, and 75.0%, P=0.407; (3) the multivariate logistic regression analysis showed that elder age (OR 1.053, 95%CI 1.027-1.080, P<0.001) and diabetes (OR 2.194, 95%CI 1.186-4.057, P=0.012) were correlated with multiple intracranial plaques, diurnal fluctuation pattern of blood pressure was no correlated with intracranial plaque burden (multiple plaques) and vulnerability (IPH), and moderate-severe stenosis of large intracranial artery (all P>0.05). 

Conclusions The increasing age and diabetes were independent predictors of multiple intracranial plaques, and the diurnal fluctuation pattern of blood pressure was no correlated with intracranial atherosclerotic plaque burden and vulnerability.

Key words:  Ischemic stroke; Atherosclerosis; Dipper blood pressure

摘要：

目的 调查血压昼夜节律变化与颅内动脉粥样硬化斑块负荷及易损性的相关性。 

方法 回顾性分析一个颅内动脉粥样硬化卒中影像队列中的267例卒中患者的临床及影像特征，根据24 h动态血压将其分为杓型血压组、非杓型血压组和反杓型血压组，通过高分辨磁共振血管壁成像及图像分析获得颅内动脉Willis环近端血管壁斑块特征，包括最大管壁厚度、斑块内出血、中重度狭窄（狭窄程度≥50%）、多发斑块（斑块数量≥3个）等指标。比较3组基线特征及颅内动脉粥样硬化斑块特征，校正混杂因素后，采用logistic回归分析血压昼夜节律变化模式与颅内动脉粥样硬化斑块特征的关系。 

结果 杓型血压组、非杓型血压组和反杓型血压组分别有36、119及112例。①反杓型血压组年龄更大（反杓型血压组∶非杓型血压组∶杓型血压组=67.3∶64.6∶61.9岁，P=0.042），合并糖尿病比例更高（反杓型血压组∶非杓型血压组∶杓型血压组=46.4%∶41.2%∶22.2%，P=0.037）；血压指标中，反杓型血压组24 h平均收缩压更高（反杓型血压组∶非杓型血压组∶杓型血压组=144∶139∶136 mmHg，P=0.025）。②杓型血压组、非杓型血压组和反杓型血压组的平均最大管壁厚度分别为2.39 mm、2.48 mm和2.52 mm（P=0.554），斑块内出血比例分别33.3%（12/36）、36.1%（43/119）和37.5%（42/112）（P=0.901）；3组中重度狭窄及多发斑块比例差异亦无统计学意义（中重度狭窄比例在杓型血压组、非杓型血压组和反杓型血压组分别为22.2%、32.8%和37.5%，P=0.236；多发斑块比例在3组分别为63.9%、73.9%和75.0%，P=0.407）。③多因素logistic回归分析结果显示：年龄（OR 1.053，95%CI 1.027～1.080，P＜0.001）和糖尿病（OR 2.194，95%CI 1.186～4.057，P=0.012）与颅内动脉多发斑块独立相关。未发现血压昼夜节律变化模式与颅内动脉多发斑块、中重度狭窄以及斑块内出血存在相关性（均P＞0.05）。 

结论 增龄和糖尿病是颅内动脉多发斑块的独立危险因素，血压昼夜节律变化与颅内动脉粥样硬化斑块易损性之间的关系还有待进一步研究。

关键词:   缺血性卒中；动脉粥样硬化；杓型血压