Pandemic of the aging society - sporadic cerebral small vessel disease

Assessment of cheese sign and its association with vascular risk factors: Data from PUMCH dementia cohort

BACKGROUND

In the clinic, practitioners encounter many patients with an abnormal pattern of dense punctate magnetic resonance imaging (MRI) signal in the basal ganglia, a phenomenon known as "cheese sign". This sign is reported as common in cerebrovascular diseases, dementia, and old age. Recently, cheese sign has been speculated to consist of dense perivascular space (PVS). This study aimed to assess the lesion types of cheese sign and analyze the correlation between this sign and vascular disease risk factors.

METHODS

A total of 812 patients from Peking Union Medical College Hospital (PUMCH) dementia cohort were enrolled. We analyzed the relationship between cheese sign and vascular risk. For assessing cheese sign and defining its degree, the abnormal punctate signals were classified into basal ganglia hyperintensity (BGH), PVS, lacunae/infarctions and microbleeds, and counted separately. Each type of lesion was rated on a four-level scale, and then the sum was calculated; this total was defined as the cheese sign score. Fazekas and Age-Related White Matter Changes (ARWMC) scores were used to evaluate the paraventricular, deep, and subcortical gray/white matter hyperintensities.

RESULTS

A total of 118 patients (14.5%) in this dementia cohort were found to have cheese sign. Age (odds ratio [OR]: 1.090, 95% confidence interval [CI]: 1.064-1.120, P <0.001), hypertension (OR: 1.828, 95% CI: 1.123-2.983, P = 0.014), and stroke (OR: 1.901, 95% CI: 1.092-3.259, P = 0.025) were risk factors for cheese sign. There was no significant relationship between diabetes, hyperlipidemia, and cheese sign. The main components of cheese sign were BGH, PVS, and lacunae/infarction. The proportion of PVS increased with cheese sign severity.

CONCLUSIONS

The risk factors for cheese sign were hypertension, age, and stroke. Cheese sign consists of BGH, PVS, and lacunae/infarction.

Cerebrovascular pathology mediates associations between hypoxemia during rapid eye movement sleep and medial temporal lobe structure and function in older adults

Obstructive sleep apnea (OSA) is common in older adults and is associated with medial temporal lobe (MTL) degeneration and memory decline in aging and Alzheimer's disease (AD). However, the underlying mechanisms linking OSA to MTL degeneration and impaired memory remains unclear. By combining magnetic resonance imaging (MRI) assessments of cerebrovascular pathology and MTL structure with clinical polysomnography and assessment of overnight emotional memory retention in older adults at risk for AD, cerebrovascular pathology in fronto-parietal brain regions was shown to statistically mediate the relationship between OSA-related hypoxemia, particularly during rapid eye movement (REM) sleep, and entorhinal cortical thickness. Reduced entorhinal cortical thickness was, in turn, associated with impaired overnight retention in mnemonic discrimination ability across emotional valences for high similarity lures. These findings identify cerebrovascular pathology as a contributing mechanism linking hypoxemia to MTL degeneration and impaired sleep-dependent memory in older adults.

Performance of the walking trail making test in older adults with white matter hyperintensities

BACKGROUND

Several studies have reported that the walking trail making test (WTMT) completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments. We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities (WMH).

AIM

To explore the performance in the WTMT in older people with WMH.

METHODS

In this single-center, observational study, 25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age, gender, and educational level who were undergoing physical examination in our hospital during the same period served as the control group. The participants completed the WTMT-A and WTMT-B to obtain their gait parameters, including WTMT-A completion time, WTMT-B completion time, speed, step length, cadence, and stance phase percent. White matter lesions were scored according to the Fazekas scale. Multiple neuropsychological assessments were carried out to assess cognitive function. The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.

RESULTS

Patients with WMH performed significantly worse on the choice reaction test (CRT) (0.51 ± 0.09 s vs 0.44 ± 0.06 s, P = 0.007), verbal fluency test (VFT, 14.2 ± 2.75 vs 16.65 ± 3.54, P = 0.012), and digit symbol substitution test (16.00 ± 2.75 vs 18.40 ± 3.27, P = 0.010) than participants in the control group. The WMH group also required significantly more time to complete the WTMT-A (93.00 ± 10.76 s vs 70.55 ± 11.28 s, P < 0.001) and WTMT-B (109.72 ± 12.26 s vs 82.85 ± 7.90 s, P < 0.001). WTMT-A completion time was positively correlated with CRT time (r = 0.460, P = 0.001), while WTMT-B completion time was negatively correlated with VFT (r = -0.391, P = 0.008). On the WTMT-A, only speed was found to statistically differ between the WMH and control groups (0.803 ± 0.096 vs 0.975 ± 0.050 m/s, P < 0.001), whereas on the WTMT-B, the WMH group exhibited a significantly lower speed (0.778 ± 0.111 vs 0.970 ± 0.053 m/s, P < 0.001) and cadence (82.600 ± 4.140 vs 85.500 ± 5.020 steps/m, P = 0.039), as well as a higher stance phase percentage (65.061 ± 1.813% vs 63.513 ± 2.465%, P = 0.019) relative to controls.

CONCLUSION

Older adults with WMH showed obviously poorer WTMT performance. WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH.

Progress on Prevention and Treatment of Cerebral Small Vascular Disease Using Integrative Medicine

Cerebral small vessel disease (CSVD) is a senile brain lesion caused by the abnormal structure and function of arterioles, venules and capillaries in the aging brain. The etiology of CSVD is complex, and disease is often asymptomatic in its early stages. However, as CSVD develops, brain disorders may occur, such as stroke, cognitive dysfunction, dyskinesia and mood disorders, and heart, kidney, eye and systemic disorders. As the population continues to age, the burden of CSVD is increasing. Moreover, there is an urgent need for better screening methods and diagnostic markers for CSVD, in addition to preventive and asymptomatic- and mild-stage treatments. Integrative medicine (IM), which combines the holistic concepts and syndrome differentiations of Chinese medicine with modern medical perspectives, has unique advantages for the prevention and treatment of CSVD. In this review, we summarize the biological markers, ultrasound and imaging features, disease-related genes and risk factors relevant to CSVD diagnosis and screening. Furthermore, we discuss IM-based CSVD prevention and treatment strategies to stimulate further research in this field.

Aged Patients With Severe Small Vessel Disease Exhibit Poor Bimanual Coordination During the Anti-Phase Horizontal Line Drawing Task

The present study explores whether SVD affects bimanual coordination, which is easier to detect than by conventional, MRI-based methods. We tested nine severe SVD patients, eight non-severe (i.e., moderate or mild) SVD patients, eleven healthy age-matched controls, and eight young adults. They were grouped according to Fazekas scale and by age. Participants performed horizontal line drawings with both hands simultaneously on two pen tablets. The movements consisted of rhythmic patterns where participants used both hands to draw horizontal lines in anti-phase on two pen tablets. Each participant underwent a series of neuropsychiatric assessments. Results showed that SVD patients exhibited in each hand smaller horizontal movement amplitudes with variability larger compared to the healthy age-matched controls. Only movement amplitudes appeared to decrease significantly with severity of SVD. Interestingly, we found no relevant differences between the age-matched, elderly controls and the young controls. Therefore, this effect appeared indicative of SVD. The variability of the lines orthogonal to the horizontal lines of the left, non-dominant hand differed only between the severe SVD group and the other groups. Furthermore, partial correlations demonstrated that the mean horizontal movement amplitude of the left hand was positively associated with the clock drawing test score, and the inter-manual asynchrony of the horizontal movements was positively associated with the Trail Making Test-B time. These results indicated that SVD patients show poor bimanual coordination, as reflected by spatial features such as movement amplitudes and variabilities, and abnormal bimanual coordination was associated with executive dysfunction.

Diffusion tensor imaging pipeline measures of cerebral white matter integrity: An overview of recent advances and prospects

Cerebral small vessel disease (CSVD) is a leading cause of age-related microvascular cognitive decline, resulting in significant morbidity and decreased quality of life. Despite a progress on its key pathophysiological bases and general acceptance of key terms from neuroimaging findings as observed on the magnetic resonance imaging (MRI), key questions on CSVD remain elusive. Enhanced relationships and reliable lesion studies, such as white matter tractography using diffusion-based MRI (dMRI) are necessary in order to improve the assessment of white matter architecture and connectivity in CSVD. Diffusion tensor imaging (DTI) and tractography is an application of dMRI that provides data that can be used to non-invasively appraise the brain white matter connections via fiber tracking and enable visualization of individual patient-specific white matter fiber tracts to reflect the extent of CSVD-associated white matter damage. However, due to a lack of standardization on various sets of software or image pipeline processing utilized in this technique that driven mostly from research setting, interpreting the findings remain contentious, especially to inform an improved diagnosis and/or prognosis of CSVD for routine clinical use. In this minireview, we highlight the advances in DTI pipeline processing and the prospect of this DTI metrics as potential imaging biomarker for CSVD, even for subclinical CSVD in at-risk individuals.