Leukoaraiosis and ambulatory blood pressure load in a healthy elderly cohort study: The PROOF study

Twenty-four-hour ambulatory blood pressure variability and association with ischemic stroke subtypes in the subacute stage

Background and purpose

Blood pressure (BP) variability (BPV) increases the risk of cerebral disease in both hemorrhagic and ischemic strokes. However, whether BPV is associated with different types of ischemic stroke remains unclear. In this study, we explored the relationship between BPV and ischemic stroke subtypes.

Methods

We enrolled consecutive patients aged 47-95 years with ischemic stroke in the subacute stage. We categorized them into four groups based on their artery atherosclerosis severity, brain magnetic resonance imaging markers, and disease history: large-artery atherosclerosis, branch atheromatous disease, small-vessel disease, and cardioembolic stroke. Twenty-four-hour ambulatory blood pressure monitoring was performed, and the mean systolic blood pressure/diastolic blood pressure, standard deviation, and coefficient of variation were calculated. A multiple logistic regression model and random forest were used to test the relationship between BP and BPV in the different types of ischemic stroke.

Results

A total of 286 patients, including 150 men (73.0 ± 12.3 years) and 136 women (77.8 ± 9.6 years) were included in the study. Of these, 86 (30.1%) patients had large-artery atherosclerosis, 76 (26.6%) had branch atheromatous disease, 82 (28.7%) had small-vessel disease, and 42 (14.7%) had cardioembolic stroke. There were statistically significant differences in BPV between subtypes of ischemic stroke in 24-h ambulatory blood pressure monitoring. The random forest model showed that BP and BPV were important features associated with ischemic stroke. Multinomial logistic regression analysis demonstrated that systolic blood pressure levels; systolic blood pressure variability at 24 h, daytime and nighttime; and nighttime diastolic blood pressure were independent risk factors for large-artery atherosclerosis after adjustment for confounders. When compared to branch atheromatous disease and small-vessel disease, nighttime diastolic blood pressure and standard deviation of diastolic blood pressure were significantly associated with patients in the cardioembolic stroke group. However, a similar statistical difference was not seen in patients with large-artery atherosclerosis.

Conclusion

The results of this study indicate a discrepancy in blood pressure variability among different ischemic stroke subtypes during the subacute stage. Higher systolic blood pressure and systolic blood pressure variability during the 24 h, daytime, and nighttime, and nighttime diastolic blood pressure were independent predictors for large-artery atherosclerosis stroke. Increased nighttime diastolic BPV was an independent risk factor for cardioembolic stroke.

Obstructive sleep apnea and white matter hyperintensities: correlation or causation?

Obstructive sleep apnea (apnea) is thought to cause small vessel ischemic episodes in the brain from hypoxic events, postulated as white matter hyperintensities (hyperintensities) identified on MRI which are implicated in cognitive decline. This study sought to evaluate these correlations. A retrospective evaluation of adults who underwent polysomnography (4/1/2016 to 4/30/2017) and a brain MRI prior to apnea diagnosis or within a year post-diagnosis was completed. MRI visual evaluation of hyperintensities using Fazekas scores were collected blind to clinical data. Collated clinical/MRI data were stratified and analyzed using chi-square, fishers t-tests, ANOVA/ANCOVA and linear regression. Stratification by apnea category revealed no significant differences in any variables including hyperintensity measures (Fazekas p=0.1584; periventricular p=0.3238; deep p=0.4618; deep total p=0.1770). Stratification by Fazekas category, periventricular and deep hyperintensities revealed increasing prevalence with age (p=0.0001); however, apnea categories were not significantly associated (Fazekas p=0.1479; periventricular p=0.3188; deep p=0.4503), nor were any individual apnea indicators. Continuous apnea measurements werre not associated with any hyperintensity factor; total deep hyperintensities were not associated with any apnea factors. Continuous BMI was not found to be associated with any apnea or hyperintensity factors. Only hypertension was noted to be associated with Fazekas (p=0.0045), deep (p=0.0010) and total deep (p=0.0021) hyperintensities; however, hypertension was not associated with apnea category (p=0.3038) or any associated factors. These data suggest apneas alone from OSA are insufficient to cause WMH, but other factors appear to contribute to the complex development of small vessel ischemic injury associated with age and cognitive decline.

Leukoaraiosis and Gray Matter Volume Alteration in Older Adults: The PROOF Study

Background and Purpose: Leukoaraiosis, also called white matter hyperintensities (WMH), is frequently encountered in the brain of older adults. During aging, gray matter structure is also highly affected. WMH or gray matter defects are commonly associated with a higher prevalence of mild cognitive impairment. However, little is known about the relationship between WMH and gray matter. Our aim was thus to explore the relationship between leukoaraiosis severity and gray matter volume in a cohort of healthy older adults.

Methods: Leukoaraiosis was rated in participants from the PROOF cohort using the Fazekas scale. Voxel-based morphometry was performed on brain scans to examine the potential link between WMH and changes of local brain volume. A neuropsychological evaluation including attentional, executive, and memory tests was also performed to explore cognition.

Results: Out of 315 75-year-old subjects, 228 had punctuate foci of leukoaraiosis and 62 had begun the confluence of foci. Leukoaraiosis was associated with a decrease of gray matter in the middle temporal gyrus, in the right medial frontal gyrus, and in the left parahippocampal gyrus. It was also associated with decreased performances in memory recall, executive functioning, and depression.

Conclusion: In a population of healthy older adults, leukoaraiosis was associated with gray matter defects and reduced cognitive performance. Controlling vascular risk factors and detecting early cerebrovascular disease may prevent, at least in part, dementia onset and progression.

Ambulatory Blood Pressure Levels in the Prediction of Progression of Cerebral Small Vessel Disease

OBJECTIVES

We aimed to study the value of ambulatory blood pressure monitoring (ABPM) in predicting the global progression of cerebral small vessel disease (cSVD).

DESIGN

Longitudinal cohort study.

SETTING

Data from the population-based Investigating Silent Strokes in Hypertensives study.

PARTICIPANTS

Individuals with hypertension who were 50 to 70 years of age and stroke free at baseline. In baseline and follow-up visits, patients underwent magnetic resonance imaging and ABPM.

MEASUREMENTS

Ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels were studied as continuous variables and dichotomized according to good or poor control on the basis of 125/75 (24 hours), 130/80 (day), and 110/65 (night) mm Hg cutoff values. Whole cSVD progression was qualitatively scored with 1 point when an incident lesion (incident lacunar infarcts, deep cerebral microbleeds, white matter hyperintensities, and basal ganglia enlarged perivascular spaces) was detected. The score ranged from 0 to 4.

RESULTS

We followed up 233 participants with a median age of 65 years within 4 years. A total of 61 (26.2%) and 23 (9.9%) subjects showed cSVD progression in one and two or more markers, respectively. Baseline ambulatory SBP and DBP and nighttime pulse pressure (PP) values were positively correlated with the number of incident cSVD lesions. Interestingly, patients without incident lesions showed greater differences between office and ambulatory BP, thus suggesting an increased white coat effect. Poor DBP control, nighttime PP, and DBP white coat effect were independently associated with cSVD progression. The inclusion of these metrics in a clinical model resulted in a significant increase in the prediction of incident lesions (integrated discrimination improvement = 9.09%; P value <.001).

CONCLUSION

ABPM may help assess cSVD risk of progression, especially by the identification of poor BP control, masked hypertension, and increased nighttime PP. J Am Geriatr Soc 68:2232-2239, 2020.

Imaging of the aging brain and development of MRI signal abnormalities

Major changes occur at the cerebral level with aging. Cerebral atrophy develops progressively. Multiple lesions related to small-vessel diseases are detected in association with cerebral atrophy including white-matter hyperintensities, lacunes, microbleeds, dilated perivascular spaces and cerebral, including cortex, atrophy. The clinical impact and predictive value of these Imaging makers were examined.

Abnormal blood pressure circadian rhythms are relevant to cerebral infarction and Leukoaraiosis in hypertensive patients

BACKGROUND

To investigate the relationships between blood pressure (BP) circadian rhythms and acute cerebral infarction (ACI), silent cerebral infarction (SCI) and the severity of leukoaraiosis in hypertensive patients.

METHODS

A retrospective case-control study was performed among hypertensive patients with 24-h ambulatory blood pressure monitoring (ABPM) and cranial magnetic resonance imaging (MRI).

RESULTS

A total of 1267 patients were enrolled. Lower nocturnal blood pressure (BP) decreases were observed in ACI patients than in controls (3.3% vs 8.2%, P<0.001). Reverse-dipper pattern (RD) and non-dipper pattern (ND) were found to be independent risk factors for ACI. In ACI patients, both RD and ND BP circadian rhythms were revealed to be independent risk factors for moderate-severe leukoaraiosis. In addition, in SCI patients, RD (OR = 1.7, 95% CI, 0.9-3.0; P = 0.047) or extreme-dipper pattern (ED) (OR = 2.9, 95% CI, 1.2-7.0; P = 0.015) were found to be independent risk factors for moderate-severe leukoaraiosis. Moreover, the greater the severity of leukoaraiosis was, the higher the ratio of abnormal BP circadian rhythms.

CONCLUSION

RD and ND BP circadian rhythms might not only be relevant to the onset of ACI but also correlate with the severity of leukoaraiosis. Thus, when modulating BP with antihypertensive drugs, the BP circadian rhythms, and not merely the BP level, should warrant more attention.

Metabolic syndrome and its components with neuron-specific enolase: a cross-sectional study in large health check-up population in China

OBJECTIVE

This study was aimed at investigating the relationship between neuron-specific enolase (NSE) and components of metabolic syndrome (MS).

DESIGN

Cross-sectional study.

SETTING

Chinese health check-up population.

PARTICIPANTS

40 684 health check-up people were enrolled in this study from year 2014 to 2016.

MAIN OUTCOME MEASURES

OR and coefficient for MS.

RESULTS

The percentage of abnormal NSE and MS was 26.85% and 8.85%, respectively. There were significant differences in sex, body mass index, drinking habit, triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), blood pressure and MS between low-NSE and high-NSE groups. In logistic regression analysis, elevated NSE was present in MS, higher body mass index, hypertriglyceridaemia, hypertension and low-HDL groups. Stepwise linear analysis showed a negative correlation between NSE and fasting blood glucose (FBG) (<6.0 mmol/L), and a positive correlation between NSE and TGs (<20 mmol/L), systolic blood pressure (75-200 mm Hg), HDL-C (0.75-2.50 mmol/L), diastolic blood pressure (<70 mm Hg) and FBG (6.00-20.00 mmol/L). Furthermore, MS was positively correlated with NSE within the range of 2.00-7.50 ng/mL, but had a negative correlation with NSE within the range of 7.50-23.00 ng/mL.

CONCLUSION

There are associations between NSE with MS and its components. The result suggests that NSE may be a potential predictor of MS. Further research could be conducted in discussing the potential mechanism involved.

Spectrum construction of differentially expressed circular RNAs in patients with leukoaraiosis and function analysis of differentially expressed genes

Circular RNAs (circRNAs) are class of endogenous RNAs that have a role in the regulation of gene expression. The present study aimed to investigate the diagnostic value and role of circRNA in the pathogenesis of leukoaraiosis (LA). The present study performed Arraystar Human circRNA Array analysis of 6 samples from LA cases and 6 samples from control cases. Differentially expressed (DE) circRNAs between two samples were identified through fold-change (>1.5-fold) screening. Afterwards, based on DE circRNAs, the gene ontology (GO) analysis of upregulated DE genes identified from DE circRNAs demonstrated that DE genes were primarily associated with cellular metabolic processes, membrane-bound organelles and binding. However, none were enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Downregulated DE genes were enriched in cellular localization, cytoplasm and kinase binding. For the KEGG pathways, the downregulated DE genes were primarily associated with the insulin signaling pathway. The results of the present study indicated that the DE genes from differently expressed circRNAs may have an important role in the pathogenesis of LA and may be a novel targfet for further research.

Prevalence of Brain MRI Markers of Hemorrhagic Risk in Patients with Stroke and Atrial Fibrillation

Background and purpose

Cerebral microbleeds (CMBs), cortical superficial siderosis, white matter lesions (WML), and cerebral atrophy may signify greater bleeding risk particularly in patients in whom anticoagulation is to be considered. We investigated their prevalence and associations with stroke type in patients with stroke and atrial fibrillation (AF).

Materials and Methods

Cross-sectional sample, Monash Medical Centre (Melbourne, Australia) between 2010 and 2013, with brain MRI. MRI abnormalities were rated using standardized methods. Logistic regression was used to study associations adjusting for age and sex.

Results

There were 170 patients, mean age 78 years (SD 9.8), 154 (90.6%) with ischemic stroke. Prevalence of MRI markers were any microbleed 49%, multiple (≥2) microbleeds 30%, confluent WMLs 18.8%, siderosis 8.9%, severe cerebral atrophy 37.7%. Combinations of the severe manifestations of these markers were much less prevalent (2.9–12.4%). Compared with ischemic stroke, those with hemorrhagic stroke were more likely to have ≥10 microbleeds (OR 5.50 95% CI 1.46–20.77, p = 0.012) and siderosis (OR 6.24, 95% CI 1.74–22.40, p = 0.005). Siderosis was associated with multiple microbleeds (OR 8.14, 95% CI 2.38–27.86, p = 0.001). Patients admitted with hemorrhagic stroke and multiple microbleeds were more frequently anticoagulated prior to stroke (6/7, 85.7%) than in those with single (1/2, 50%) or no microbleeds (4/7, 57%).

Conclusion

Multiple CMBs, severe WML, and severe cerebral atrophy were common individually in hospitalized patients with stroke and AF, but less so in combination. A higher burden of CMBs may be associated with intracerebral hemorrhage in stroke patients with AF.

Serum neuron specific enolase could predict subclinical brain damage and the subsequent occurrence of brain related vascular events during follow up in essential hypertension

The object of this work was to explore if blood based biomarkers of brain damage could predict subclinical brain lesions and clinical outcome during follow-up in asymptomatic hypertensive patients. This was a cross-sectional study including 101 patients with essential hypertension and no clinical evidence of neurological disease and 53 healthy controls, followed by a longitudinal study of 62 hypertensive patients for an average of 33 months. Serum concentrations of two brain specific proteins (S100B and neuron specific enolase - NSE) were determined at inclusion. Fundoscopic exploration, brain MRI and echocardiographic studies were also performed. Clinical outcome at follow-up was registered: transient ischemic attack (TIA), stroke, vascular headache or migraine, cardiovascular events and death. Higher serum NSE and S100B concentrations were observed in hypertensive patients; and multiple regression analysis revealed independent associations of clinical variables and more severe white matter lesions only with NSE concentration. A panel combining two clinical variables (blood pressure>140/90 and years of hypertension>10) and serum NSE>13 μg/L predicted more severe white matter lesions with 80% sensitivity and 94.4% specificity. Higher NSE levels at inclusion were associated not only with the occurrence of vascular events related with the CNS (stroke, TIA and vascular headache), but also with an earlier presentation of these events during the follow-up period. Serum NSE concentration could be a useful biomarker to predict subclinical brain damage and future vascular events related with the CNS in hypertension. Blood based biomarkers could aid in filtering hypertensive patients with a higher risk of cerebrovascular disease for brain MRI scanning.