Leukoaraiosis is associated with clinical symptom severity,poor neurological function prognosis and stroke recurrence in mild intracerebral hemorrhage:a prospective multi-center cohort study

Leukoaraiosis(LA)results from ischemic injury in small cerebral vessels,which may be attributable to decreased vascular density,reduced cerebrovascular angiogenesis,decreased cerebral blood flow,or microcirculatory dysfunction in the brain.In this study,we enrolled 357 patients with mild intracerebral hemorrhage(ICH)from five hospitals in China and analyzed the relationships between LA and clinical symptom severity at admission,neurological function prognosis at 3 months,and 1-year stroke recurrence.Patients were divided into groups based on Fazekas scale scores:no LA(n=83),mild LA(n=64),moderate LA(n=98)and severe LA(n=112).More severe LA,larger hematoma volume,and higher blood glucose level at admission were associated with more severe neurological deficit.More severe LA,older age and larger hematoma volume were associated with worse neurological function prognosis at 3 months.In addition,moderate-to-severe LA,admission glucose and symptom-free cerebral infarction were associated with 1-year stroke recurrence.These findings suggest that LA severity may be a potential marker of individual ICH vulnerability,which can be characterized by poor tolerance to intracerebral attack or poor recovery ability after ICH.Evaluating LA severity in patients with mild ICH may help neurologists to optimize treatment protocols.This study was approved by the Ethics Committee of Ruijin Hospital Affiliated to Shanghai Jiao Tong University(approval No.12)on March 10,2011.

Lacunar infarction with leukoaraiosis may aggravate cognitive dysfunction

This study semi-quantitatively analyzed the effects of leukoaraiosis.Patients with moderate or severe lacunar infarction were found to exhibit low scores on the Montreal Cognitive Assessment Scale （F=12.02,P=0.000）,and prolonged P300 Cz2.0 latency （F=16.04,P=0.000）.Correlation analysis revealed that the occurrence of leukoaraiosis was negatively correlated with Montreal Cognitive Assessment scores （r=-0.416,P=0.000）,and positively correlated with P300 Cz2.0 latency （r=0.538,P=0.000）.These findings indicate that leukoaraiosis aggravates cognitive impairment in patients with lacunar infarction,such that more severe leukoaraiosis is associated with more severe cognitive decline.

Correlation of diffusion tensor imaging and cognitive function in patients with leukoaraiosis

Conventional imaging technology does not measure white matter lesions of the brain or cognitive impairment. Diffusion tensor imaging is able to detect changes in the microstructure of white matter, and correlating vascular risk factors with cognitive dysfunction seems feasible using this technique. A total of 60 leukoaraiosis patients and 30 healthy elderly controls received diffusion tensor imaging examination to detect the average diffusion coefficient and fractional anisotropy of leukoaraiosis lesion and normal white matter. Leukoaraiosis severity positively correlated with average diffusion coefficient but negatively correlated with fraction anisotropy. Neuropsychology tests （mini-mental state examination） were related to average diffusion coefficient and fraction anisotropy of normal white matter in leukoaraiosis patients, especially in the anterior horn and centrum semiovale. The average diffusion coefficient and fraction anisotropy of leukoaraiosis displayed characteristic changes. Therefore, diffusion tensor imaging can detect the macrostructural changes in white matter with normal magnetic resonance imaging, and these changes are related to cognitive function. Application of diffusion tensor imaging techniques to analyze the correlation between vascular risk factors and cognitive dysfunction is feasible.

DDAH2(-449 G/C) G allele is positively associated with leukoaraiosis in northeastern China: a double-blind, intergroup comparison, case-control study

Cerebrovascular endothelial dysfunction is involved in the progression of leukoaraiosis. Asymmetric dimethylarginine is a competitive inhibitor of nitric oxide, which is highly expressed in patients with leukoaraiosis. Dimethylarginine dimethylaminohydrolase(DDAH) is a hydrolytic enzyme that is primarily responsible for eliminating asymmetric dimethylarginine, and it plays a role in the pathogenesis of cardiovascular and cerebrovascular diseases. The DDAH2 subtype is expressed in organs rich in induced nitric oxide synthase, including the heart, the placenta, and the cerebral endothelium during cerebral ischemia, in the stress state, or under neurotoxicity. Overexpression of the DDAH2 gene can inhibit asymmetric dimethylarginine-induced peripheral circulating endothelial cell dysfunction. However, it is unknown whether this polymorphism regulates plasma asymmetric dimethylarginine levels in patients with leukoaraiosis. In this doubleblind study, we recruited 46 patients with leukoaraiosis and 46 healthy, matched controls. Plasma asymmetric dimethylarginine levels were determined using enzyme-linked immunoassays. Genomic DNA was isolated from whole blood samples, and polymerase chain reaction, Sma I restriction enzyme digestion, restriction fragment length polymorphisms, and agarose electrophoresis were used to detect DDAH2(-449 G/C) gene polymorphisms. The results revealed that 95.65% of leukoaraiosis patients had recessive genetic models(GG and CG), while 89.13% of healthy control subjects had dominant genetic models(CC and CG). There was a significant difference in the genotype composition ratio between leukoaraiosis patients and healthy controls(P = 0.0002). The frequency of G alleles in the leukoaraiosis patients(71.74%) was significantly higher than in healthy controls, whereas the frequency of C alleles was lower(χ~2 = 13.9580, P = 0.0002). Furthermore, asymmetric dimethylarginine concentrations in subjects with the GG genotype were significantly higher than in subjects with the CG and CC genotypes(Kruskal–Wallis H = 24.5955, P < 0.0001). In addition, the GG genotype of DDAH2(-449 G/C) was more common in patients with leukoaraiosis. These findings suggest that the G allele of DDAH2(-449 G/C) is a risk factor for leukoaraiosis morbidity and is correlated with high levels of asymmetric dimethylarginine. This study was approved by the Institutional Ethics Committee of the 2~(nd) Affiliated Hospital of Harbin Medical University of China(approval No. KY2016-177) on July 28, 2016.

Cognitive Functional Impairment and Hemodynamic Changes in Patients with Symptomatic Leukoaraiosis

Objective: The pathogenesis of leukoaraiosis is still unclear. Many studies have determined that changes in the hemodynamics associated with leukoaraiosis, impaired cerebrovascular reserve, and intracranial hypoperfusion can lead to various clinical manifestations such as motor or cognitive impairment. The purpose of this study was to investigate the relationship between cognitive functional changes and imaging characteristics in patients with symptomatic leukoaraiosis, and to observe the corresponding changes in hemodynamics. Methods: A total of 203 Han patients (aged 43 - 93 years) with symptomatic leukoaraiosis were included in this study. Head magnetic resonance imaging was semi-quantified according to the Fazekas grading standard. Then, each patient was evaluated in terms of cognitive (Montreal scale) and executive function (trail-making test A [TMTA] and TMTB). Specifically, the TMTA asks patients to connect points on a piece of paper numbered from 1 to 25 in order and the TMTB asks patients to arrange numbers and letters in alternating order. In the current work, revised versions of these tests used are to include numbers in square and circular shapes where the shapes needed to be arranged in alternating order. The time required to complete the TMTA and TMTB was recorded. The changes in the blood flow velocity of the middle cerebral artery were also observed using routine Transcranial Doppler ultrasound and the breath-holding test. The dynamic curves of blood flow velocity during the breath-holding test were examined. Results: The cognitive and executive functions of patients with leukoaraiosis are related to the classification of image-based disease characteristics. In this sense, the more serious the leukoaraiosis is, the larger the impairment of cognitive and executive function is. According to the breath-holding test, the peak pattern of the blood flow velocity in the middle cerebral artery was significantly different between the various grades of leukoaraiosis. The peak type of Fazekas grade 0 and I was in the same direction, while the peak type of Fazekas grade II and III was significantly opposed (both p Conclusions: The impairment of cognitive and executive functions in patients with leukoaraiosis correlates with the severity of image-based disease manifestations, which are generally depicted as intracranial hypoperfusion.

Overview-Research Progress of Leukoaraiosis

In 1987, Hachinski et al. [1] proposed Leukoaraiosis (LA) as an imaging academic term. Since then, LA and other cerebrovascular diseases have become the research focus of scholars at home and abroad. However, the molecular, cellular and pathogenesis of cerebrovascular disease are still unclear. Cerebral small vessel disease is caused by the lesions of perforating arteries, capillaries and veins of the brain. Modern imaging technology makes it possible to classify these diseases that can not be directly distinguished in clinical practice. The imaging features of cerebral infarction include cerebral microvascular atrophy. At present, a large number of studies have been carried out around LA, such as the pathogenesis, risk factors, imaging manifestations and classification, pathophysiological changes, hemodynamics, gene polymorphism and so on. In addition, although LA belongs to the category of cerebral small vessel disease, more scholars believe that there are countless links between large artery atherosclerosis and LA, and to some extent, have the same pathogenesis. This paper reviews the following aspects.

Research progress on risk factors for leukoaraiosis

Leukoaraiosis (LA), a term of neural imaging, is a disease which clinically causes cognitive dysfunction and gait disorders, eventually leads to persistent or progressive cognitive and neural dysfunction, seriously affects patients' daily lives. Early detection and identification of LA and its risk factors and early intervention may be of help to improve the quality of patients' living in the future. The research progress on risk factors for LA was reviewed in this study.

Vascular cognitive impairment, a cardiovascular complication

Over the past two decades, the term vascular cognitive impairment(VCI) has been used to refer to a spectrum of cognitive decline characterized by executive dysfunction, associated with vascular pathology. With 30% of stroke survivors showing cognitive impairments, it is regarded as the most common cause of cognitive impairment. This is a narrative review of available literature citing sources from Pub Med, MEDLINE and Google Scholar. VCI has a high prevalence both before and after a stroke and is associated with great economic and caregiver burden. Despite this, there is no standardized diagnostic criteria for VCI. Hypertension has been identified as a risk factor for VCI and causes changes in cerebral vessel structure and function predisposing to lacuna infarcts and small vessel haemorrhages in the frontostriatal loop leading to executive dysfunction and other cognitive impairments. Current trials have shown promising results in the use of antihypertensive medications in the management of VCI and prevention of disease progression to vascular dementia. Prevention of VCI is necessary in light of the looming dementia pandemic. All patients with cardiovascular risk factors would therefore benefit from cognitive screening with screening instruments sensitive to executive dysfunction as well as prompt and adequate control of hypertension.

Predicting Mortality and Functional Outcomes after Ischemic Stroke: External Validation of a Prognostic Model

Background: We previously developed predictive models for 3-month mortality and modified Rankin Score (mRS) after ischemic stroke. Aim: The aim was to test model validity for 3-month mortality and mRS after ischemic stroke in two independent data sets. Methods: Our derivation models used data from 451 subjects with ischemic stroke in 1999 enrolled in the Greater Cincinnati/Northern Kentucky Stroke Study (GCKNSS). We utilized two separate cohorts of ischemic strokes through GCKNSS (460 in 2005 and 504 in 2010) to assess external validity by utilizing measures of agreement between predicted and observed values, calibration, and discrimination using Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis. Results: The 3-month mortality model performed well in the validation datasets with an average prediction error (Brier score) of 0.045 for 2005 and 0.053 for 2010 and excellent discrimination with an area under the curve of 0.86 (95% CI: 0.79, 0.93) for 2005 and 0.84 (0.76, 0.92) for 2010. Predicted 3-month mRS also performed well in the validation datasets with R2 of 0.57 for 2005 and 0.50 for 2010 and a root mean square error of 0.85 for 2005 and 1.05 for 2010. Predicted mRS tended to be higher than actual in both validation datasets. Re-estimation of the model parameters for age and severe white matter hyperintensity in both 2005 and 2010, and for diabetes in 2005, improved predictive accuracy. Conclusions: Our previously developed stroke models performed well in two study periods, suggesting validity of the model predictions.

A Study on the Correlation Between Cerebral Small Vascular Disease and Constitution Types of Traditional Chinese Medicine

Objective:To study the correlation between cerebral small vascular disease and constitution types of Traditional Chinese Medicine(TCM).Methods:The severity of lacunar infarction and leukoaraiosis were graded in 230 patients with cerebral small vascular disease,and they were divided into TCM constitution types.The survey of TCM constitution types was carried out by using standardized TCM constitution scale,and order multivariate Logistic regression was used to analyze the correlation between TCM constitution types with severity of lacunar infarction and leukoaraiosis.Results:Yang-deficiency(阳虚)constitution,blood-stasis constitution and phlegm-dampness constitution were the most common TCM constitution types in patients with lacunar infarction,accounting for 33.7%,12.5%,11.5%respectively.Yang-deficiency constitution,blood-stasis constitution and Yin-deficiency(阴虚)constitution were the most common TCM constitution types in patients with leukoaraiosis,accounting for 28.8%,18.5%,13.7%respectively.There were significant differences in lacunar infarction of Yang-deficiency constitution and blood stasis constitution(P<0.05),and there were significant differences in leukoaraiosis of phlegmdampness constitution and blood-stasis constitution(P<0.05).Single factor analysis showed that the main risk factors of lacunar infarction were age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution,and the main risk factors of leukoaraiosis were age,smoking,hypertensive disease,phlegm-dampness constitution and blood-stasis constitution.The ordered multivariate Logistic regression analysis found that the severity of lacunar infarction was closely related to age,and the severity of leukoplosis was closely related to age,smoking and hypertension disease.Conclusion:TCM constitution types of lacunar infarction in patients with small cerebral vascular disease is mainly Yang-deficiency constitution and blood-stasis constitution,and the risk factors include age,smoking,alcohol consumption,Yang-deficiency constitution and blood-stasis constitution.Age is closely related with lacunar infarction.TCM constitution types with leukoaraiosis are mainly phlegm-dampness constitution and blood-stasis constitution,and the risk factors are age,smoking,hypertension disease,phlegm-dampness constitution and blood-stasis constitution.Age,smoking and hypertension disease are closely related with leukoaraiosis.

An association between the location of white matter changes and the behavioral and psychological symptoms of dementia in Alzheimer's disease patients

Objective:The frontal lobe may be involved in circuits associated with depression,apathy,aggression,and other psychiatric symptoms.Although white matter changes(WMC)are related to the severity of behavioral and psychological symptoms of dementia(BPSD)in patients with Alzheimer’s disease(AD),it is unclear which part of the WMC may play the most important role in BPSD.This study was designed to investigate the relationship between the location of WMC and the severity of BPSD in AD patients.Methods:Among patients diagnosed with Alzheimer’s disease between 2009 and2014,387 patients were retrospectively reviewed after those with pre‐existing organic brain syndrome,psychiatric diseases,or toxic‐metabolic encephalopathy were excluded.Patients’demographic and laboratory data,WMC measured with brain computed tomography and scored using the age‐related white matter changes(ARWMC)scale,and neuropsychological tests,including the cognitive abilities screening instrument(CASI),the Mini‐Mental State Examination(MMSE),the clinical dementia rating scale with sum‐box(CDR‐SB),and the neuropsychiatric inventory(NPI)were analyzed.Results:There was no significant difference in the NPI between patients with and without a history of stroke,hypertension,and diabetes.No significant difference in the NPI was identified between different sexes or different Apolipoprotein E(APOE)alleles.The NPI score was significantly correlated with the duration of education(r=–0.4515,P=0.0172),CASI(r=–0.2915,P<0.0001),MMSE(r=–0.8476,P<0.0001),and CDR‐SB(r=2.2839,P<0.0001).WMC in the right frontal lobe showed a significant difference in NPI in comparison to those without WMC(P=0.0255).After adjusting for age,duration of education,and CASI,WMC in the right frontal lobe remained significantly associated with the NPI score(β=3.8934,P=0.042).Conclusions:WMC involving the right frontal lobe may play an important role in the BPSD in AD patients during their dementia diagnosis.Further studies are necessary to confirm whether controlling the risk factors of WMC can slow the progression of BPSD.