Editorial comment--The progression of leukoaraiosis

The mechanism of impaired delayed recall verbal memory function in Parkinson's disease with orthostatic hypotension: a multiple imaging study

Introduction

Orthostatic hypotension (OH) frequently accompanies autonomic dysfunction and is an important risk factor for cognitive impairment in Parkinson's disease (PD). However, the association between different cognitive functions and OH in PD patients is not yet fully understood.

Methods

This study aimed to evaluate the scores of different cognitive domains and multiple parameters using different imaging techniques on PD patients with or without OH. A total number of 31 PD patients with OH (n = 20) and without OH (n = 11) were recruited from the Department of Neurology, Beijing Xuanwu Hospital for this study. All patients underwent beat-to-beat non-invasive blood pressure recordings and an active standing test to evaluate neurogenic OH and a global neuropsychological test to assess cognitive function. All patients underwent dynamic cerebral autoregulation (dCA) measurement, brain magnetic resonance imaging (MRI), and brain 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT).

Results

The results showed that OH patients had poor delayed recall verbal memory when compared with the PD patients without OH (1.75 ± 1.59 vs. 3.10 ± 1.73, p = 0.042). The dCA test indicated a significant difference in the right very low-frequency (VLF) gain between two groups (1.27 ± 0.17 vs. 1.10 ± 0.26, p = 0.045) and the brain 18F-FDG PET/CT indicated a significant difference in the SUV (right medial temporal lobe) to SUV (occipital lobe) ratio (0.60 ± 0.08 vs. 0.67 ± 0.11, p = 0.049). Meanwhile, these two imaging parameters were negatively correlated (p < 0.001). Furthermore, the score of a delayed recall verbal memory in the OH group was positively correlated with the right medial temporal lobe to occipital lobe ratio (p < 0.001) and was negatively correlated with the right VLF gain (p = 0.023).

Discussion

PD with OH patients had poor delayed recall memory, which might have been caused by the decreased metabolic dysfunction of specific medial temporal lobe due to the impaired dCA ability.

Atherosclerosis, inflammatory factor changes, cognitive disorder and vascular endothelial functions in patients with different grades of leukoaraiosis

OBJECTIVE

To study the atherosclerosis (AS), inflammatory factor level, cognitive disorder and vascular endothelial functions in patients with different grades of leukoaraiosis (LA), and to explore the correlations of different grades of LA with cognitive disorder.

METHODS

A total of 180 patients with cerebral infarction admitted and treated in the Department of Neurology of our hospital were selected, and they were graded according to the Tarvonen-shcolder standard, with 45 patients in each group. The atherosclerotic plaques of the patients were detected via a color Doppler ultrasound system and magnetic resonance imaging (MRI). Their inflammatory factor levels were determined using enzyme-linked immunosorbent assay (ELISA). The cognitive function was scored based on the mini-mental state examination (MMSE), and the levels of malondialdehyde (MDA), superoxide dismutase (SOD), endothelin (ET) and nitric oxide (NO) were measured to evaluate vascular endothelial functions.

RESULTS

According to the comparisons among four groups of the patients, the incidence rate of AS was gradually increased among patients with different grades of LA (p < 0.05). With the aggravation of LA, the levels of inflammatory factors in patients were obviously increased (p < 0.05). LA patients had evidently lowered MMSE scores and levels of SOD and NO, but notably raised inflammatory factors C-reactive protein (CRP) and matrix metalloproteinase-9 (MMP-9) and vascular endothelial function indices MDA and ET (p < 0.05).

CONCLUSION

The occurrence of LA is implicated with the increasing levels of inflammatory factors in the patients, aggregation of cognitive dysfunction and impairment vascular endothelial functions.

Cognitive performance after first ever stroke related to progression of vascular brain damage: a 2 year follow up CT scan study

BACKGROUND

Stroke is one of the most common causes of cognitive impairment in the elderly. Ischaemic brain damage (white matter lesions and silent infarcts) progresses in a substantial number of stroke patients. The aim of this study was to investigate whether the progression of ischaemic brain damage is associated with cognitive functioning after first ever stroke.

METHODS

A total of 101 stroke patients were followed up for 2 years. Neuropsychological functioning was assessed at 1, 6, 12, and 24 months after stroke. Computed tomography was performed on all patients at baseline and 2 years after stroke. Progression in white matter lesions and (silent) infarcts was recorded.

RESULTS

Patients with progressive vascular brain damage performed worse on cognitive tasks, both 1 and 24 months after stroke, yet change in cognitive functioning was not different from that of patients without progressive vascular damage. During the follow up, improvement was noticed on most cognitive domains.

CONCLUSIONS

Although patients with progressive vascular brain damage after a first stroke performed somewhat worse on cognitive tests than those without such damage, both groups showed an improved or stable performance 2 years later. Thus, there is not a simple relation between progression of ischaemic brain damage and decline in cognitive functioning after first ever stroke.

White Matter Hyperintensity on Cranial Magnetic Resonance Imaging

BACKGROUND AND PURPOSE

We have previously reported that several "silent" infarcts found on magnetic resonance imaging (MRI) were a risk factor for stroke. Several recent reports have shown that high white matter grade (WMG) and increasing WMG over time were risk factors for stroke. We tested the hypothesis that high WMG > or =2 was a predictor of risk for stroke, independent of other risk factors.

METHODS

We examined the extent of white matter hyperintensity on cranial MRI of 3293 participants from the Cardiovascular Health Study (CHS). The degree of white matter hyperintensity was graded from least severe (grade=0) to most severe (grade=9). Participants were followed-up for an average of 7 years for the occurrence of a stroke. Clinical stroke diagnoses were based on hospital records reviewed by an adjudication committee expert in stroke diagnosis. During this period, 278 strokes occurred. Results The relative risk of stroke increased significantly as the WMG increased. The risk of stroke was 2.8% per year for participants with high WMG (grades > or =5), compared with only 0.6% for participants with grades 0 to 1.Conclusions The risk of stroke with high WMG is independent of traditional stroke risk factors and persists when controlling for MRI infarcts, another subclinical imaging marker of cerebrovascular disease. Assessment of white matter disease may be valuable in assessing future risk of stroke.