A new rating scale for age-related white matter changes applicable to MRI and CT

The vestibular and oculomotor dysfunction in Fabry disease: a cohort study in China

OBJECTIVE

Whereas a few studies have evaluated vestibular involvement in Fabry disease (FD), the relationship between vestibular/oculomotor abnormalities and disease-specific biomarkers remain unclear. Therefore, we seek to evaluate these quantitatively and analyze their relationship with disease phenotype and biomarkers in FD.

METHODS

This cohort study enrolled 37 Chinese FD patients registered in our center. The vestibular/oculomotor examinations were performed, including the videonystagmography, the caloric test and the video head-impulse test. Statistical analyses were made between different subgroups of patients.

RESULTS

Visuo-oculomotor dysfunctions were found in 30/37 (81.1%) patients. Vestibulo-oculomotor dysfunctions were revealed in 9/22 (40.9%) patients. Statistical tests showed: (1) significantly higher Mainz Severity Score Index in patients with prolonged saccade latency [20(18,33) VS 13(9,22), p = 0.008] and vestibulo-oculomotor dysfunction [23(20,31) VS 9(5.5,12.5), p = 0.024], (2) significantly higher total small-vessel disease score in subgroups with prolonged saccade latency [2.5(1,3.5) VS 1(0,2), p = 0.038], defective smooth pursuit [3(2,4) VS 1(0,2), p = 0.003], defective optokinetic nystagmus [4(2,4) VS 1(0.2), p = 0.009] and vestibulo-oculomotor dysfunction [1(1,3) VS 0(0,1), p = 0.028], (3) significantly lower α-Gal A activity (μmol/L/h) in subgroups with defective saccades [0.44(0.25,1.93) VS 1.85(0.75,5.52), p = 0.015] and defective smooth pursuit [0.30(0.17,0.44) VS 0.96(0.39,2.40), p = 0.008], and (4) significantly elevated plasma globotriaosylsphingosine (ng/ml) in patients with defective saccades [74.16(11.05,89.18) VS 10.64(7.08,36.32), p = 0.034], than in patients without those abnormalities.

CONCLUSION

A high incidence of extensive vestibular and oculomotor dysfunction was observed in patients with FD, with the neuro-otological dysfunction being closely related to the disease burden and biomarkers like α-Gal A activity and lyso-Gb3.

Gender disparities in myotonic dystrophy 1

Myotonic Dystrophy Type 1 (DM1) is a complex, inherited disorder characterized by significant clinical heterogeneity, affecting multiple organ systems with varying severity and age of onset. It is a multisystemic disorder with a wide range of clinical presentations that lead to symptoms and complications associated with various body systems. Predicting the overall phenotype and prognosis is challenging due to the lack of a single determining factor, complicating medical management and clinical trials. While extensive research has explored the genetic and molecular mechanisms of DM1, the influence of gender on disease manifestations, progression, and outcomes remains elusive. Emerging evidence suggests that male patients often experience greater morbidity and mortality with severe muscular, cardiac, central nervous system, and respiratory impairments, while females are more prone to ophthalmological, gastrointestinal, and endocrine complications. Potential gender-based differences in inheritance patterns also require further investigation. Despite these disparities, gender-specific considerations are largely absent in clinical management and research, limiting the development of targeted therapeutic strategies. This review provides a comprehensive analysis of gender-related differences in DM1, emphasizing their implications for disease prognosis, diagnosis, and treatment. Recognizing gender as a crucial factor in DM1 research and clinical practice could improve patient outcomes and more personalized therapeutic approaches.

Protocol for a prospective cohort study to determine the multimodal biomarkers of delirium and new dementia after acute illness in older adults: ORCHARD-PS

INTRODUCTION

Delirium is common in the older hospital population and is often precipitated by acute illness. Delirium is associated with poor outcomes including subsequent cognitive decline and dementia and may therefore be a modifiable risk factor for dementia. However, the mechanisms underpinning the delirium-dementia relationship and the role of coexisting acute illness factors remain uncertain. Current biomarker studies of delirium have limitations including lack of detailed delirium characterisation with few studies on neurodegenerative or neuroimaging biomarkers especially in the acute setting. The Oxford and Reading Cognitive Health After Recovery from acute illness and Delirium-Prospective Study (ORCHARD-PS) aims to elucidate the pathophysiology of delirium and subsequent cognitive decline after acute illness in older adults, through acquisition of multimodal biomarkers for deep phenotyping of delirium and acute illness, and follow-up for incident dementia.

METHODS AND ANALYSIS

ORCHARD-PS is a bi-centre, prospective cohort study. Consecutive eligible patients requiring acute hospital admission or assessment are identified by the relevant acute clinical care team. All patients age >65 years without advanced dementia, nursing home residence, end-stage frailty or terminal illness are eligible. Details of potential participants are communicated to the research team and written informed consent or consultee agreement is obtained. Participants are interviewed as soon as possible after admission/assessment using a structured proforma.Data are collected on demographics, diagnosis and comorbidities, social and functional background. Delirium is assessed using the 4A's test, Confusion Assessment Method (long-form), Observational Scale of Level of Arousal, Richmond Agitation-Sedation Scale and Memorial Delirium Assessment Scale and diagnosed using the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. Delirium is categorised by time of onset (prevalent vs incident), dementia status, motoric subtype, severity and duration. Cognitive tests include the 10-point Abbreviated Mental Test and Montreal Cognitive Assessment. Participants are reassessed every 48-72 hours if remaining in hospital. Informant questionnaire data and interview are supplemented by hand searching of medical records and linkage to electronic patient records for nursing risk assessments, vital observations, laboratory results and International Classification of Diseases, Tenth Revision diagnostic and procedure codes.In-person follow-up with more detailed cognitive testing and informant interview is undertaken at 3 months, and 1 and 3 years supplemented with indirect follow-up using medical records. Blood banking is performed at baseline and all follow-ups for future biomarker analyses. CT-brain and MRI-brain imaging acquired as part of standard care is obtained for quantification of brain atrophy and white matter disease/stroke supplemented by research CT-brain imaging. Outcomes include length of hospitalisation, change in care needs, institutionalisation, mortality, readmission, longitudinal changes in cognitive and functional status and incident dementia. Biomarker associations with delirium, and with incident dementia on follow-up, will be determined using logistic or Cox regression as appropriate, unadjusted and adjusted for covariates including demographics, baseline cognition, frailty, comorbidity and apolipoprotein E genotype.

ETHICS AND DISSEMINATION

ORCHARD-PS is approved by the South Central-Berkshire Research Ethics Committee (REC Reference: 23/SC/0199). Results will be disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

ISRCTN24171810.

Segmentation of Leukoaraiosis on Noncontrast Head CT Using CT-MRI Paired Data Without Human Annotation

OBJECTIVE

Evaluating leukoaraiosis (LA) on CT is challenging due to its low contrast and similarity to parenchymal gliosis. We developed and validated a deep learning algorithm for LA segmentation using CT-MRIFLAIR paired data from a multicenter Korean registry and tested it in a US dataset.

METHODS

We constructed a large multicenter dataset of CT-FLAIR MRI pairs. Using validated software to segment white matter hyperintensity (WMH) on FLAIR, we generated pseudo-ground-truth LA labels on CT through deformable image registration. A 2D nnU-Net architecture was trained solely on CT images and registered masks. Performance was evaluated using the Dice similarity coefficient (DSC), concordance correlation coefficient (CCC), and Pearson correlation across internal, external, and US validation cohorts. Clinical associations of predicted LA volume with age, risk factors, and poststroke outcomes were also analyzed.

RESULTS

The external test set yielded a DSC of 0.527, with high volume correlations against registered LA (r = 0.953) and WMH (r = 0.951). In the external testing and US datasets, predicted LA volumes correlated with Fazekas grade (r = 0.832-0.891) and the correlations were consistent across CT vendors and infarct volumes. In an independent clinical cohort (n = 867), LA volume was independently associated with age, vascular risk factors, and 3-month functional outcomes.

INTERPRETATION

Our deep learning algorithm offers a reproducible method for LA segmentation on CT, bridging the gap between CT and MRI assessments in patients with ischemic stroke.

Neuroimaging biomarkers on routine Computed Tomography (CT) after acute stroke and their association with post-stroke delirium: A cohort study

BACKGROUND

Delirium affects a quarter of patients after acute stroke and predicts poorer outcomes. The aim of this pragmatic study was to determine whether either qualitative assessment or quantitative assessments of the regional atrophy obtained from routinely performed computed tomography (CT) brain imaging could identify patients most at risk of developing delirium.

METHODS

We recruited 95 patients with acute stroke (age ≥60) (ischaemic or intracerebral haemorrhage) over one year. Follow-up for delirium and cognition was performed at 1, 3, 5, 7, 14, 21, 28 days, 4 months and 12 months. All participants underwent routine CT brain (Toshiba 64-slice or 128-slice scanner) (within 24 h of stroke onset). White matter lesions and atrophy were rated qualitatively (mild, moderate, severe). Atrophy in multiple specific areas was measured quantitatively.

RESULTS

Twenty-six (27 %) developed delirium during the 12 months of follow-up. On univariable analysis, delirium was associated with increasing age, being female, less independent in pre-stroke activities of daily living, pre-existing cognitive impairment, increasing stroke severity, having had a total anterior circulation stroke and global cerebral atrophy on brain CT. Multivariable analysis demonstrated that only global cerebral atrophy, being female and having a more severe stroke predicted delirium. This model accounted for between 38 % and 55 % of the variance in delirium. For quantitative CT analysis, on univariable analysis, delirium was associated with atrophy in several specific brain areas. On multivariable analysis, only NIHSS (for every one point increase OR 1.23, 95 % CI 1.06-1.43; p = 0.006)) and cistern ambiens ratio (OR 1.41, 95 % CI 1.48-4.96; p = 0.028) were significantly associated. This model accounted for between 35.1 % and 51.2 % of delirium variance.

CONCLUSION

Clinical variables together with either qualitative atrophy assessment or cistern ambiens ratio on routine CT brain could identify stroke patients most at risk of delirium and to stratify patients in clinical trials of delirium prevention and treatment.

The impact of white matter lesions on seizure recurrence after first epileptic seizures in the elderly: a prospective study

BACKGROUND

Despite considerable previous research, to what degree white matter lesions (WML) may be epileptogenic remains unclear. Therefore, the decision of initiating treatment with antiseizure medication (ASM) can be challenging in patients with only WML on neuroimaging. In this prospective study we assessed whether the prevalence, localization or severity of WML impact the risk of seizure recurrence in patients aged 60 years or older after first-time seizures.

METHODS

Data was analyzed from 168 patients, aged ≥ 60 years-old who had experienced a previous unprovoked seizure and had either a potentially epileptogenic lesion or WML on neuroimaging. The frequency of seizure recurrence was documented after 6, 12, and 24 months. Pearson´s chi-square test of independence (categorical variables) and the independent Student´s t-test (continuous variables) were used to analyze intergroup differences. Binary logistic regressions were calculated to examine the influence of WML locations as a predictor of seizure recurrence. Kaplan-Meier survival analyses and log-rank statistics were performed to determine the cumulative recurrence rates between the groups.

RESULTS

Fifteen patients had only potentially epileptogenic lesions on neuroimaging (EPI) and 93 showed WML only (OWML). Sixty patients showed both of them on neuroimaging (EWML). Frontal and parieto-occipital were the predominant WML locations. Neither severity nor location of WML had a significant impact on recurrence rates. The two-year cumulative probability of becoming seizure-free was significantly lower in the EPI group compared to the EWML (χ2 [1] = 4.425, p = 0.035) and the OWML group (χ2 [1] = 13.094, p < 0.001). A significant association between interictal epileptiform discharges in EEG and seizure recurrence was found in OWML patients (p = 0.004).

CONCLUSION

We could not find any association between prevalence, severity or location of WML and seizure recurrence after first seizures in the elderly. Therefore, treatment with ASM should be started with caution in those patients. Our results show a trend of WML not having epileptogenic potential, but further studies are needed to get better evidence.

TRIAL REGISTRATION

ClinicalTrials.gov Protocol Registration and Results, NCT06836687, AZ 199/17, release: 03/19/2024 retrospectively registered. https://register.

CLINICALTRIALS

gov/prs/beta/studies/S000EBC700000025/recordSummary.

A robust automated segmentation method for white matter hyperintensity of vascular-origin

White matter hyperintensity (WMH) is a primary manifestation of small vessel disease (SVD), leading to vascular cognitive impairment and other disorders. Accurate WMH quantification is vital for diagnosis and prognosis, but current automatic segmentation methods often fall short, especially across different datasets. The aims of this study are to develop and validate a robust deep learning segmentation method for WMH of vascular-origin. In this study, we developed a transformer-based method for the automatic segmentation of vascular-origin WMH using both 3D T1 and 3D T2-FLAIR images. Our initial dataset comprised 126 participants with varying WMH burdens due to SVD, each with manually segmented WMH masks used for training and testing. External validation was performed on two independent datasets: the WMH Segmentation Challenge 2017 dataset (170 subjects) and an in-house vascular risk factor dataset (70 subjects), which included scans acquired on eight different MRI systems at field strengths of 1.5T, 3T, and 5T This approach enabled a comprehensive assessment of the method's generalizability across diverse imaging conditions. We further compared our method against LGA, LPA, BIANCA, UBO-detector and TrUE-Net in optimized settings. Our method consistently outperformed others, achieving a median Dice coefficient of 0.78 ± 0.09 in our primary dataset, 0.72 ± 0.15 in the external dataset 1, and 0.72 ± 0.14 in the external dataset 2. The relative volume errors were 0.15 ± 0.14, 0.50 ± 0.86, and 0.47 ± 1.02, respectively. The true positive rates were 0.81 ± 0.13, 0.92 ± 0.09, and 0.92 ± 0.12, while the false positive rates were 0.20 ± 0.09, 0.40 ± 0.18, and 0.40 ± 0.19. None of the external validation datasets were used for model training; instead, they comprise previously unseen MRI scans acquired from different scanners and protocols. This setup closely reflects real-world clinical scenarios and further demonstrates the robustness and generalizability of our model across diverse MRI systems and acquisition settings. As such, the proposed method provides a reliable solution for WMH segmentation in large-scale cohort studies.

Leukoaraiosis severity and outcomes of endovascular thrombectomy for acute ischemic stroke: a systematic review and meta-analysis

BACKGROUND

Endovascular thrombectomy (EVT) is the standard of care for eligible patients with large vessel occlusion (LVO). Yet, little is known regarding the impact of leukoaraiosis (LA) on outcomes following EVT for LVO.

PURPOSE

We conducted a systematic review and meta-analysis to investigate the impact of LA on outcomes following EVT.

MATERIALS AND METHODS

A literature search was performed in PubMed, Embase, Scopus, and Web of Science, from inception until January 7, 2024. Patients were categorized into two groups based on the level of LA: one with absent to mild LA (AMLA) and the other with moderate to severe LA (MSLA). The primary outcome of interest was 90-day modified Rankin Scale (mRS) 0-2. Secondary outcomes included symptomatic intracranial hemorrhage (sICH), thrombolysis in cerebral infarction (TICI) score 2b-3, and mortality. Using R software, we calculated pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI).

RESULTS

We included 18 studies with 7022 patients. MSLA was associated with lower rates of mRS 0-2 (OR, 0.32 [95% CI: 0.26-0.41]; p < 0.001), similar rates of TICI 2b-3 (OR, 0.91 [95% CI: 0.77-1.07]; p = 0.235) and sICH (OR, 1.18 [95% CI: 0.92-1.51]; p = 0.202), and greater rates of mortality (OR, 2.89 [95% CI: 2.38-3.52]; p < 0.001) compared to AMLA.

CONCLUSION

MSLA is associated with lower rates of mRS 0-2 and worse safety outcomes following EVT for LVO, despite similar rates of TICI 2b-3. Future prospective studies should further study MSLA as a prognosticator following EVT.

KEY POINTS

Question Does the severity of LA impact functional and safety outcomes following EVT for acute ischemic stroke due to LVO? Findings Moderate-to-severe LA was associated with lower rates of good functional outcome and higher mortality following EVT, despite similar rates of successful reperfusion and sICH. Clinical relevance LA severity is an independent prognostic factor in EVT outcomes. Identifying patients with moderate-to-severe LA can aid in risk stratification and post-procedural management, optimizing individualized stroke treatment and follow-up strategies.

Exploring the Link between Hypertension and Cerebral White Matter Changes in Chronic Kidney Disease

BACKGROUND

Patients diagnosed with chronic kidney disease (CKD) are at a higher risk of encephalopathy, a condition exacerbated by the presence of various chronic diseases. Hypertension is a significant risk factor for brain damage in the general population but is limitedly discussed in patients with CKD. Brain magnetic resonance imaging (MRI) is an excellent tool for evaluating cerebral white matter lesions. Most previous studies showed the association between hypertension and cerebral white matter lesions in the general population but were less focused on CKD patients. Therefore, the present study aims to investigate the effect of hypertension on the cerebral white matter lesions of brain MRI in patients with CKD.

METHODS

In this retrospective study, we enrolled 1,749 CKD patients who underwent brain MRIs to evaluate their brain lesions in Kaohsiung Medical University Hospital. The cerebral white matter hyperintensities (WMHs) on MRI were evaluated according to the Fazekas scale, including separate periventricular and deep white matter lesions from grade 0 to grade 3. The multivariable ordinal regression model was analyzed to determine the independent association between hypertension or blood pressure and cerebral WMHs with adjustment of controlling age, sex, education, comorbidities (hyperlipidemia, cerebrovascular disease, chronic heart failure), laboratory data (hemoglobin, albumin, triglyceride, estimated glomerular filtration rate).

RESULTS

Hypertension was associated with the Fazekas scale of periventricular lesions in multivariable-adjusted ordinal regression analysis (odds ratio [OR] 1.63, 95% confidence interval [CI] 1.15-2.30) after full adjustment. However, the hypertension comorbidities did not associate with the Fazekas scale of deep white matter lesions in the fully adjusted model (OR 1.24, 95% CI [0.89-1.75]). A positive association between blood pressure (per 10 mm Hg increase) and the Fazekas scale was mainly on diastolic blood pressure rather than systolic blood pressure.

CONCLUSIONS

In CKD patients, hypertension was associated with brain white matter damage; in particular, Fazekas scale of periventricular lesions. Further study is needed to evaluate adequate blood pressure control to decrease the risk of brain damage in CKD patients.

Donanemab: Appropriate use recommendations

Donanemab (Kisunla®), an IgG1 monoclonal antibody targeting N-terminal pyroglutamate-modified forms of amyloid-β, is approved in the United States for treatment of early symptomatic Alzheimer's disease (AD). Appropriate Use Recommendations (AUR) were developed to guide the implementation of donanemab in real-world practice, prioritizing safety considerations and opportunity for effectiveness. The AUR were developed by the AD and Related Disorders Therapeutic Workgroup by consensus, integrating available data and expert opinion. Appropriate candidates for donanemab treatment include persons with mild cognitive impairment or mild dementia due to AD (Clinical Stages 3-4, MMSE 20-30) who have biomarker confirmation of AD pathology by PET or CSF. Tau PET is not required for eligibility. Apolipoprotein E (APOE) genotyping should be performed prior to treatment to inform an individual's risk of developing Amyloid-Related Imaging Abnormalities (ARIA). Pre-treatment MRI should be obtained no more than 12 months prior to treatment. Patients with findings of >4 cerebral microbleeds, cortical superficial siderosis or a major vascular contribution to cognitive impairment should be excluded from treatment. The decision to initiate therapy should be grounded in a shared decision-making process that emphasizes the patient's values and goals of care. Donanemab is administered as a monthly intravenous infusion. Surveillance MRIs to evaluate for ARIA should be performed prior to the 2nd, 3rd, 4th and 7th infusions, prior to the 12th dose in higher risk individuals, and at any time ARIA is suspected clinically. Clinicians may consider discontinuing treatment if amyloid clearance is demonstrated by amyloid PET, typically obtained 12-18 months after initiating treatment.

MRS demonstrates elevated brain glutathione in vascular mild cognitive impairment compared to cognitively normal coronary artery disease controls

INTRODUCTION

Oxidative stress (OS) is implicated in dementia. While elevated peripheral OS biomarkers were observed in vascular mild cognitive impairment (vMCI), the role of central antioxidants remains unclear. We assessed levels of the major brain antioxidant glutathione (GSH) in vMCI compared to cognitively normal coronary artery disease (CAD) controls (CN).

METHODS

In vivo tissue-corrected GSH in the anterior cingulate cortex (ACC) and occipital cortex (OC) were quantified in persons with vMCI and CN using MEscher-GArwood Point RESolved magnetic resonance Spectroscopy.

RESULTS

Among participants (vMCI, n = 22, age [mean ± SD] = 67.4 ± 7.3; CN, n = 21, age = 66.7 ± 7.8), ACC-GSH (i.u. ± SD) was higher in vMCI (4.42 ± 0.59) versus CN (3.72 ± 1.01) (Z = -2.5, p = .01), even after controlling for age and sex (B [SE] = 0.74 [0.26], p = .007). Increased ACC-GSH correlated with poorer executive function (EF) (B [SE] = -0.31 [0.14], p = .04). OC-GSH showed no effect.

DISCUSSION

Higher ACC-GSH in vMCI may reflect a compensatory response to OS. ACC-GSH was negatively correlated with EF, suggesting a linkage between regional brain antioxidants and disease-relevant cognitive domains.

HIGHLIGHTS

Brain GSH was measured in vascular MCI and matched controls using MEGA-PRESS. In contrast to GSH deficits in AD, anterior cingulate GSH was elevated in vMCI. Brain GSH was correlated with disease-relevant cognitive domains in vMCI. The GSH antioxidant system may be etiologically implicated in vMCI.

Early-phase 18F-Flortaucipir tau-PET as a proxy of brain metabolism in Alzheimer's disease: a comparison with 18F-FDG-PET and early-phase amyloid-PET

PURPOSE

As dual-phase amyloid-PET can evaluate amyloid (A) and neurodegeneration (N) with a single tracer injection, dual-phase tau-PET might be able to provide both tau (T) and N. Our study aims to assess the association of early-phase tau-PET scans and 18F-fluorodeoxyglucose (FDG) PET and their comparability in discriminating Alzheimer's disease (AD) patients and differentiating neurodegenerative patterns.

METHODS

58 subjects evaluated at the Geneva Memory Center underwent dual-phase 18F-Flortaucipir-PET with early-phase acquisition (eTAU) and 18F-FDG-PET within 1 year. A subsample of 36 participants also underwent dual-phase amyloid-PET (eAMY). Standardized uptake value ratios (SUVRs) were calculated to assess the correlation of eTAU and their respective 18F-FDG-PET and eAMY scans. Hypometabolism and hypoperfusion maps and their spatial overlap were also evaluated at the individual level visually and semiquantitatively. Receiver operating characteristic analyses were performed to compare the discriminative power of eTAU, FDG, and eAMY SUVR between A-/T- and A+/T + participants.

RESULTS

Strong positive correlations were found between eTAU and FDG SUVRs (r = 0.84, p < 0.001) and eTAU and eAMY SUVRs (r > 0.87, p < 0.001). Clusters of significant hypoperfusion with good correspondence to hypometabolism topographies were found at the individual level, independently of the underlying neurodegenerative patterns. Both eTAU and FDG SUVRs significantly distinguished A+/T + from A-/T- individuals (AUCeTAU=0.604, AUCFDG=0.748) with FDG performing better than eTAU (p = 0.04). eAMY and eTAU SUVR showed comparable discriminative power.

CONCLUSION

Early-phase 18F-Flortaucipir-PET can provide perfusion information closely related to brain regional glucose metabolism and perfusion measured by early-phase amyloid-PET, even if less accurate than FDG-PET as a biomarker for neurodegeneration.

Imaging Interstitial Fluids and Extracellular Matrix in Cerebrovascular Disorders: Current Perspectives and Clinical Applications

This article provides a comprehensive review of current neuroimaging techniques for visualizing and quantifying extracellular matrix (ECM) components and interstitial fluid (ISF) dynamics in cerebrovascular disorders. It examines how alterations in ECM composition and ISF movement patterns correlate with various cerebrovascular pathologies, including ischemic stroke, frontotemporal dementia, cerebral small vessel disease, Alzhheimer's disease, and vascular dementia. The review emphasizes novel imaging markers specific to ECM/ISF alterations and their utility in differentiating various cerebrovascular pathologies. Special attention is given to the clinical applications of these imaging techniques for early disease detection, monitoring progression, and guiding therapeutic interventions.

Impact of enlarged perivascular spaces in the basal ganglia on gait in cerebral small vessel disease

BACKGROUND

Gait disturbance is a prevalent characteristic of cerebral small vessel disease (CSVD), yet the underlying mechanisms remain largely unclear.

AIMES

To test the hypothesis that enlarged perivascular spaces in the basal ganglia (BG-EPVS) are related to gait performance in individuals with CSVD and the elderly.

METHODS

This cross-sectional study included 138 CSVD patients and 62 healthy elderly controls who underwent quantitative gait analysis. Neuroimaging markers, including BG-EPVS, white matter hyperintensities (WMH), lacunes, and cerebral microbleeds (CMB), were assessed using MRI. Principal component analysis (PCA) was used to reduce the dimensionality of multiple gait indicators. Linear regression models were employed to examine the relationship between BG-EPVS and the principal component values of gait performance, with WMH as a potential mediator.

RESULTS

Compared to healthy controls, CSVD patients exhibited significantly prolonged stance and double-support phases, shortened swing phase, reduced gait speed, increased step width, and decreased stride length and step height (p < 0.05 for all comparisons). Higher BG-EPVS grades were independently associated with poorer gait performance in both CSVD patients (p = 0.012) and all subjects (p = 0.001), even after adjusting for other CSVD markers. WMH partially mediated the relationship between BG-EPVS and gait performance, accounting for 18.2% of the total effect in CSVD patients and 24.9% of the total effects in all subjects.

CONCLUSION

BG-EPVS is independently associated with gait disturbances in both CSVD patients and the elderly. These findings underscore the importance of early gait assessment in the aging population. Further longitudinal research is needed to confirm these associations.

Associations between cerebral small vessel disease and reduced forced vital capacity and expiratory volume in a general healthy Swedish elder population study-Good Aging in Skåne

BackgroundCerebral small vessel disease (CSVD) is one of the most important causes of cognitive decline. Only a few previous studies have evaluated lung function measures in relation to brain neuropathological changes, and even less studies on specific lesions and areas that could shed light on mechanisms of CSVD.ObjectiveThe aim was to study the association between lung function and CSVD in the general elder population.Methods379 participants, aged 72-87 years from the general population study 'Good Aging in Skåne study (GÅS)'were investigated with a 3 T MRI brain examination and spirometry. Z-scores of FEV1 and FVC were calculated using the GLI 2012 equations. Age-adjusted associations between white matter hyperintensities (WMH), medial temporal lobe atrophy (MTA), lacunar infarction, cerebral atrophies and cerebral microbleeds and lung function were calculated and stratified for sex.ResultsDecreased FEV1 and FVC z-scores below ≤ -1.0 were both associated with increased risk of WMI and global cortical atrophy. Decreased FVC z-scores were also associated with MTA and lacunar infarction in women and precuneus atrophy in men. The associations for WMH, MTA and lacunar infarctions and higher STRIVE score were noted among women, but not among men. FEV1 z scores were not related to diabetes, coronary artery disease or stroke.ConclusionsLower lung function was associated to MRI markers of CSVD in this general healthy population, particularly with WMH, especially for women. Although possible shared risk factors exist between lung and heart disease, lung function should be recognized in future studies on CSVD.

Risk factors and clinical significance of neurodegenerative co-pathologies in symptomatic cerebral small vessel disease

BACKGROUND

Cerebral small vessel disease (CSVD) often coexists with neurodegenerative pathologies, yet their role remains underexplored. This study aims to determine their prevalence, risk factors, and cognitive effects in patients with deep perforator arteriopathy (DPA) or cerebral amyloid angiopathy (CAA) using the biomarker-based ATN classification.

METHODS

In this cross-sectional study 186 patients (median age 75 years, 41% females, 111 with probable CAA, 75 with DPA) underwent MRI for analysis of CSVD severity and etiology, and lumbar puncture for analysis of cerebrospinal fluid amyloid-β 42/40 ratio, phosphorylated-tau, total-tau and neurofilament light. ATN profiles were related to clinical characteristics, MRI markers and cognitive performance in multivariate regression models.

RESULTS

Among CSVD patients, 30% had normal biomarkers (A-T-N-), 33% were within the AD pathology continuum (A + T ± N ± : 47% in CAA vs. 13% in DPA, p < .001), and 37% showed non-AD pathological changes (A-T ± N + : 53% in DPA vs. 25% in CAA, p < .001). The AD pathology continuum was associated with a severe lobar hemorrhagic phenotype and cognitive impairment, while non-AD pathological change was related to CSVD severity, history of stroke and similarly cognitive impairment. Both pathological ATN profiles were further related to lower MMSE scores (A + T ± N ± : B = - 3.3, p = .006; A-T ± N + : B = - 2.7, p = .021).

CONCLUSIONS

Using biomarkers, this study confirms in vivo that CSVD frequently co-occurs with neurodegenerative pathologies, exerting detrimental effects on cognitive health.

WMH-DualTasker: A Weakly Supervised Deep Learning Model for Automated White Matter Hyperintensities Segmentation and Visual Rating Prediction

White matter hyperintensities (WMH) are neuroimaging markers linked to an elevated risk of cognitive decline. WMH severity is typically assessed via visual rating scales and through volumetric segmentation. While visual rating scales are commonly used in clinical practice, they offer limited descriptive power. In contrast, supervised volumetric segmentation requires manually annotated masks, which are labor-intensive and challenging to scale for large studies. Therefore, our goal was to develop an automated deep-learning model that can provide accurate and holistic quantification of WMH severity with minimal supervision. We developed WMH-DualTasker, a deep learning model that simultaneously performs voxel-wise segmentation and visual rating score prediction. The model employs self-supervised learning with transformation-invariant consistency constraints, using WMH visual ratings (ARWMC scale, range 0-30) from clinical settings as the sole supervisory signal. Additionally, we assessed its clinical utility by applying it to identify individuals with mild cognitive impairment (MCI) and to predict dementia conversion. The volumetric quantification performance of WMH-DualTasker was either superior to or on par with existing supervised methods, as demonstrated on the MICCAI-WMH dataset (N = 60, Dice = 0.602) and the SINGER dataset (N = 64, Dice = 0.608). Furthermore, the model exhibited strong agreement with clinical visual rating scales on an external dataset (SINGER, MAE = 1.880, K = 0.77). Importantly, WMH severity metrics derived from WMH-DualTasker improved predictive performance beyond conventional clinical features for MCI classification (AUC = 0.718, p < 0.001) and MCI conversion prediction (AUC = 0.652, p < 0.001) using the ADNI dataset. WMH-DualTasker substantially reduces the reliance on labor-intensive manual annotations, facilitating more efficient and scalable quantification of WMH severity in large-scale population studies. This innovative approach has the potential to advance preventive and precision medicine by enhancing the assessment and management of vascular cognitive impairment associated with WMH.

Association between cerebral small vessel disease and periodic limb movements of sleep in patients with stroke/TIA

STUDY OBJECTIVES

Periodic limb movements (PLMs) of sleep, which may be linked to increased vascular events via nighttime sympathetic overactivity, have shown associations with cerebral small vessel disease (CSVD) in small studies. This study examined the relationship between PLMs and CSVD in a larger cohort, accounting for comorbidities.

METHODS

Patients with first-ever stroke or transient ischemic attack (TIA) were retrospectively analyzed. Polysomnography assessed the PLM index (PLMI) and PLM arousal index (PLMAI). CSVD was measured using radiographic markers, including the Fazekas score, total age-related white matter changes (ARWMC) score, microbleed counts, and lacunar infarcts. Multivariable regression models analyzed the association between an elevated PLMI and PLMAI with CSVD markers.

RESULTS

This study included 86 patients (mean age 62.2 ± 14.3 years, 66.3% male, mean BMI 28.1 ± 5.7), 36 with a PLMI ≥ 5 (41.9%) and 11 with a PLMAI ≥ 5 (12.8%). Regression analyses showed that PLMI ≥ 5 and PLMAI ≥ 5 both predicted increased Fazekas and ARWMC total scores after adjusting for age, sex, BMI, and other comorbidities. Sensitivity analyses using age- and sex-specific PLMI cutoffs also showed that a PLMI exceeding the upper limit of normal predicted an increased Fazekas score and approached significance for the ARWMC score. PLMI was not significantly associated with cerebral microbleeds or lacunar infarcts.

CONCLUSIONS

In patients with first-ever minor stroke and TIA, a significant association was observed between PLMI and PLMAI with white matter hyperintensities (WMHs) after adjusting for confounders. Future studies may help determine the directionality of this association and whether PLMs independently predict CSVD.

CLINICAL TRIAL INFORMATION

Name: Sleep Disorders Managed and Assessed Rapidly in Transient Ischemic Attack (TIA) and In Early Stroke (SMARTIES). URL: https://clinicaltrials.gov/study/NCT01528462 ClinicalTrials.gov ID: NCT01528462. Name: SLEep APnea Screening Using Mobile Ambulatory Recorders After TIA/Stroke (SLEAP SMART). URL: https://clinicaltrials.gov/study/NCT02454023. ClinicalTrials.gov ID: NCT02454023.

Association of Plasma Biomarkers With Longitudinal Atrophy and Microvascular Burden on MRI Across Neurodegenerative and Cerebrovascular Diseases

BACKGROUND AND OBJECTIVES

Plasma biomarkers of Alzheimer disease (AD), neuroinflammation, and neurodegeneration are increasingly being used in clinical trials for diagnosis and monitoring of dementia. However, their association with longitudinal structural brain MRI changes, an important outcome measure across neurodegenerative and cerebrovascular diseases, is less known. We investigated how baseline plasma biomarkers reflect MRI markers of progression over time in patients with neurodegenerative and cerebrovascular diseases.

METHODS

This longitudinal cohort study included patients from the Ontario Neurodegenerative Disease Research Initiative diagnosed with AD or mild cognitive impairment (AD/MCI), Parkinson disease (PD), frontotemporal dementia spectrum disorders (FTD), or cerebrovascular disease (CVD), followed annually for 2 years. Recruitment took place at specialized university-based dementia, movement disorders, and/or stroke clinics in the province of ON, Canada. MRI outcomes included markers of cerebral atrophy (ventricular CSF and regional gray matter volumes) and of small vessel disease pathology (white matter hyperintensity [WMH], perivascular spaces, and lacunar volumes). Hemorrhagic markers at baseline were also included. Plasma levels of glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), phosphorylated tau181 and tau217 (p-tau181, p-tau217), and β-amyloid (Aβ42/40) were quantified from blood samples collected at baseline using Simoa and used as predictors in linear mixed models adjusted for time (months), age, sex, apolipoprotein E (APOE)-ε4 carrier status, kidney function, vascular risk factors, microtubule-associated protein tau (MAPT) diplotypes, waist-hip circumference ratio, and disease duration.

RESULTS

We analyzed 1,240 MRIs from 473 patients (age: 69.2 ± 7.4 [range: 49-87]; 32.8% women). Elevated baseline levels of GFAP, NfL, p-tau181, and p-tau217, and to a lesser extent decreased levels of Aβ42/40, were significantly associated with more cerebral atrophy and WMH burden at baseline (|B| = 0.02 to 1.69, p = 0.044 to <0.001) and with progression over time (|B| = 0.001 to 0.028, p = 0.049 to <0.001) in the pooled disease-agnostic group. Within disease-specific cohorts, GFAP and NfL were associated with cerebral atrophy and/or small vessel disease copathology in AD/MCI, PD, FTD, or CVD. P-tau181 and p-tau217 were associated with cerebral atrophy and/or small vessel disease copathology in AD/MCI, CVD, PD-MCI, or PD-dementia.

DISCUSSION

Selected plasma biomarkers seem useful as prognosis and monitoring tools of longitudinal imaging changes within real-world populations of neurodegenerative and/or cerebrovascular diseases, and provide insight into overlap across diseases in shared pathologic burden.

Deep learning assisted retinal microvasculature assessment and cerebral small vessel disease in Fabry disease

PURPOSE

The aim of this study was to assess retinal microvascular parameters (RMPs) in Fabry disease (FD) using deep learning, and analyze the correlation with brain lesions related to cerebral small vessel disease (CSVD).

METHODS

In this retrospective case control study, fundus images from 27 FD patients and 27 age- and sex-matched healthy subjects were collected. RMPs, encompassing diameter, density, symmetry, bifurcation, and tortuosity, were quantified. Laboratory examination results, Mainz severity score index (MSSI) scores, and a brain magnetic resonance imaging scan for CSVD scores were extracted and their relationships with RMPs was analyzed.

RESULTS

Utilizing artificial intelligence-assisted analysis, compared with controls, FD patients exhibited reduced diameter (p = 0.001 for central retinal artery equivalent, p = 0.049 for central retinal vein equivalent), density (p < 0.001 for vessel area density, p = 0.001 for length density), fractal dimension (p < 0.001), and heightened arteriolar and venular asymmetry ratios (p = 0.002 and p = 0.037, respectively), venular curvature tortuosity (p = 0.037), and simple tortuosity (p = 0.037) in retinal microvascular networks. Gender-based differences in RMPs were observed among FD patients. Furthermore, RMPs were significantly associated with disease markers such as plasma globotriaosylsphingosine and α-galactosidase A activity, as well as MSSI scores. Notably, there was a significant negative correlation between the arteriolar asymmetry ratio and CSVD-related scores (age-related white matter changes: r =  - 0.683, p = 0.001; Fazekas: r =  - 0.673, p = 0.001; Lacuna: r =  - 0.453, p = 0.045; small vessel diseases: r =  - 0.721, p = 0.012; global cortical atrophy: r =  - 0.582, p = 0.009).

CONCLUSIONS

Fabry disease patients demonstrated increased vascular tortuosity and asymmetry, reduced density and diameter, and a simpler fractal dimension in retinal microvasculature. These microvascular characteristics may serve as preliminary indicators for assessing brain lesions and could represent potential novel biomarkers for CSVD, aiding in the monitoring of FD severity and progression.

Association of metabolic dysfunction-associated fatty liver disease with white matter hyperintensity and cognitive decline: A longitudinal cohort study

AIMS

Metabolic dysfunction-associated fatty liver disease (MAFLD) has recently been proposed to describe the hepatic steatosis associated with metabolic abnormalities. Substantial evidence has shown that hepatic steatosis may be linked with cognitive impairment and dementia. This study aimed to clarify the association between MAFLD and brain structural and cognitive changes.

MATERIALS AND METHODS

We analysed data from 2155 participants with both baseline and 4-year follow-up brain magnetic resonance images and neuropsychological measures from the Ansan cohort of the Korean Genome Epidemiology Study. The presence of hepatic steatosis was defined as a liver attenuation index (LAI) value <5 Hounsfield units using computed tomography.

RESULTS

Over a median follow-up of 4.1 years, MAFLD was associated with an increased risk of white matter hyperintensity (WMH) (RR 1.35; 95% CI 1.09-1.66, p = 0.006), but not with brain volume changes. When examined by individual components of MAFLD, the presence of hepatic steatosis was an independent factor associated with the risk of WMH regardless of metabolic derangements. Lower LAI values were linearly associated with greater executive function Z score decline (p = 0.007). This relationship was more evident in the non-obese group (body mass index <25 kg/m2, p for interaction = 0.003).

CONCLUSIONS

MAFLD was associated with an increased risk of WMH over 4.1 years in middle-aged adults. The hepatic steatosis itself was independently associated with an increased risk of WMH regardless of comorbid metabolic abnormalities. The degree of hepatic steatosis was associated with decreased executive function, especially in non-obese individuals.

A point-based cognitive impairment scoring system for southeast Asian adults

BACKGROUND

Cognitive impairment is a growing concern in Southeast Asian populations, where the burden of cerebrovascular disease (CeVD) is high. Currently, there is no point-based scoring system for identifying cognitive impairment in these populations.

OBJECTIVE

To develop and validate a simple point-based Cognitive Impairment Scoring System (CISS) for identifying individuals with cognitive impairment no dementia (CIND) and concomitant CeVD in Southeast Asian populations.

DESIGN

A cross-sectional study using data from two population-based studies.

SETTING

Community-based setting in Southeast Asia.

PARTICIPANTS

1,511 Southeast Asian adults (664 with CIND, 44.0 %).

MEASURES

Two CISS measures were developed: a basic measure including 11 easily assessable risk factors, and an extended measure incorporating seven additional neuroimaging markers. Performance was evaluated using receiver operating characteristic analysis (AUC) and calibration plots.

RESULTS

The AUC for CISS-basic and CISS-extended were 0.81 (95 %CI, 0.76-0.86) and 0.85 (95 %CI, 0.81-0.89), respectively. Calibration plots indicated satisfactory fit for both the basic measure (p=0.82) and the extended measure (p=0.17). The basic measure included age, gender, ethnicity, education, systolic blood pressure, BMI, smoking history, diabetes, hyperlipidemia, stroke history, and mild/moderate depression. The extended measure added neuroimaging markers of CeVD and brain atrophy.

CONCLUSION

The CISS provides a quick, objective, and clinically relevant tool for assessing cognitive impairment risk in Southeast Asian populations. The basic measure is suitable for initial community-based screenings, while the extended measure offers higher specificity for probable diagnosis. This point-based system enables rapid estimation of cognitive status without requiring complex calculations, potentially improving early detection and management of cognitive impairment in clinical practice.

Clinical and metabolic profiles in behavioural frontotemporal dementia: Impact of age at onset

AIM

Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disorder, with considerable variability of age-at-onset. We explored clinical and metabolic differences between early- and late-onset behavioural FTD (bvFTD), assuming that they might represent different disease phenotypes.

MATERIALS AND METHODS

We retrospectively studied consecutive patients diagnosed with prodromal or overt bvFTD with [18F]FDG PET scan, neuropsychological assessment (NPS), and Neuropsychiatric Inventory (NPI) available at baseline. Patients were divided into three groups based on age-at-onset: early onset-bvFTD (EO-bvFTD, age<70), late onset-bvFTD (LO-bvFTD, age 70-75) and very late onset-bvFTD (vLO-bvFTD, age>75). NPS and NPI were compared between groups and in the subset of prodromal patients, to study different syndromic phenotypes. Voxel-based analysis compared brain [18F]FDG PET of EO-bvFTD, LO-bvFTD and vLO-bvFTD independently, with respect to healthy controls, to explore metabolic differences. An inter-regional metabolic covariance analysis was performed in frontal lobe subregions, to explore differences in brain connectivity. Moreover, we supported our result using a correlation-based approach on clinical and metabolic variables.

RESULTS

101 bvFTD (62 prodromal bvFTD) were enrolled (EO-bvFTD: n = 36, prodromal n = 21; LO-bvFTD: n = 36, prodromal: n = 22; vLO-bvFTD: n = 29, prodromal: n = 19). Greater verbal memory deficit was evident in LO-bvFTD and vLO-bvFTD compared to EO-bvFTD (immediate recall: p = .018; p = .024; delayed recall: both p = .001, respectively), with similar results in the subset of prodromal patients. EO-bvFTD and LO-bvFTD had a higher behavioural severity than vLO-bvFTD. LO-bvFTD and vLO-bvFTD showed more widespread relative hypometabolism, with a greater involvement of posterior, subcortical and temporo-limbic regions compared with EO-bvFTD. Moreover, vLO-bvFTD showed a different pattern of intrafrontal metabolic covariance compared to EO-bvFTD and LO-bvFTD.

DISCUSSION

The cognitive-behavioural profile of bvFTD differs between early- and late-onset, already from the prodromal stage of the disease. Both metabolic pattern and functional connectivity vary based on age-at-onset. Understanding these differences could contribute to improve diagnostic accuracy and understanding the underling pathological heterogeneity.

Assessment of Inter-Reader Reliability of Fazekas Scoring on Magnetic Resonance Imaging of the Brain in Adult Patients with Sickle Cell Disease

Background/Objectives: Cerebral white matter disease is a common finding in patients with sickle cell that has been linked to cognitive impairment. However, there is no standardized approach for quantification of the cerebral disease burden. The Fazekas score is widely used to quantify the burden of white matter disease in chronic small vessel disease. However, its utility in sickle cell disease, specifically the inter-rater variability, has not been established. Methods: A patient cohort was compiled for the purpose of a research ethics board (REB)-approved retrospective study of adult patients with sickle cell disease, each of whom underwent MRI/MRA between the years 2017 and 2019. A total of 90 such patients were captured. All MRI/MRA studies were performed on three Tesla MRIs. Two independent neuroradiologists assessed the axial FLAIR MRI brain sequence (see image 1) for each of the 90 patients, with the sole focus of assigning a Fazekas score (0-3) to each study as a means of quantifying the burden of ischemic white matter lesions. The neuroradiologists were blinded to the scoring assigned by their counterpart and to the clinical information. After the initial assessment was completed, studies with discrepant Fazekas scores were documented and discussed by both readers. A consensus Fazekas score was then assigned to each of these studies. Results: Cohen's weighted kappa was used as a measure of agreement between readers. The expected agreement was 74.65%, with an observed agreement of 94.44% between readers, with a kappa of 0.7808. Conclusions: We conclude on the basis of our study that there is good inter-reader reliability of Fazekas scoring on axial FLAIR MRI brain sequence in patients with sickle cell disease. The Fazekas is a promising measure that could easily be integrated in systematic evaluation of cerebrovascular lesions of adults with sickle cell disease.

The cerebellum contributes to prediction error coding in reinforcement learning in humans

Recent rodent data suggest that the cerebellum - a region typically associated with processing sensory prediction errors (PEs) - also processes PEs in reinforcement learning (RL-PEs; i.e., learning from action outcomes). We tested whether cerebellar output is necessary for RL-PE processing in regions more traditionally associated with action-outcome processing, such as striatum and anterior cingulate cortex. The feedback-related negativity (FRN) was measured as a proxy of cerebral RL-PE processing in a probabilistic feedback learning task using electroencephalography. Two complementary experiments were performed in humans. First, patients with chronic cerebellar stroke (20 male, 6 female) and matched healthy controls (19 male, 7 female) were tested. Second, single-pulse cerebellar transcranial magnetic stimulation (TMS) was applied in healthy participants (7 male, 17 female), thus implementing a virtual lesion approach. Consistent with previous studies, learning of action-outcome associations was intact with only minor changes in behavioural flexibility. Importantly, no significant RL-PE processing was observed in the FRN in patients with cerebellar stroke, and in participants receiving cerebellar TMS. Findings in both experiments show that RL-PE processing in the forebrain depends on cerebellar output in humans, complementing and extending previous findings in rodents.Significance statement While processing of prediction errors in reinforcement learning (RL-PEs) is usually attributed to midbrain and forebrain, recent rodent studies have recorded RL-PE signals in the cerebellum. It is not yet clear whether these cerebellar RL-PE signals contribute to RL-PE processing in the forebrain/midbrain. In the current study, we could show that forebrain RL-PE coding is blunted when the cerebellum is affected across two complementary lesion models (patients with cerebellar stroke, cerebellar TMS). Our results support direct involvement of the cerebellum in RL-PE processing. We can further show that the cerebellum is necessary for RL-PE coding in the forebrain.

More severe vascular remodeling in deep brain regions caused by hemodynamic differences is a potential mechanism of hypertensive cerebral small vessel disease

In hypertension-associated arteriolosclerosis cerebral small vessel disease (CSVD), various studies have shown that MRI-detected lesions-such as lacunes, white matter hyperintensities, enlarged perivascular spaces, and cerebral microbleeds-are more prevalent in deep brain regions (DBR) than in the cortex. However, the underlying mechanisms remain poorly understood. We propose that differential vascular remodeling between DBR small vessels and superficial cortical branches contributes to this heterogeneity. Using a stroke-prone renovascular hypertensive rat (RHRsp) model, we observed pronounced changes in vessel density, diameter, extracellular matrix deposition, and smooth muscle cell alterations in DBR small arteries compared to that of the cortex. These findings were further confirmed in human brain tissue of our study. Additionally, our mathematical modeling indicated greater hemodynamic alterations in DBR vessels, with increased shear and circumferential stress under hypertension conditions. Overall, our study highlights more severe vascular remodeling and hemodynamic changes in the deep brain regions, where CSVD-associated MRI lesions are frequently detected.

Prediction of dementia using CT imaging in stroke (PRODUCTS)

INTRODUCTION

A better understanding of who will develop dementia can inform patient care. Although MRI offers prognostic insights, access is limited globally, whereas CT-imaging is readily available in acute stroke. We explored the prognostic utility of acute CT-imaging for predicting dementia.

PATIENTS AND METHODS

We included stroke or transient ischaemic attack (TIA) survivors from participating stroke centres in Scotland. Acute CT-scans were rated using ordinal scales for neurodegenerative and cerebrovascular changes (old infarcts, white matter lesions (WMLs), medial temporal lobe atrophy (MTA), and global atrophy (GA)) and combined together to a 'brain-frailty' score. Dementia status was established at 18-months following stroke or TIA.

RESULTS

Among 195 participants, 33% had dementia after 3 years of follow-up. High brain-frailty score (⩾2/4) correlated with higher risk of dementia (HR (95% CI) 6.02 (1.89-19.21)). As individual predictor, severe MTA was most strongly associated with dementia (adjusted HR (95% CI) 2.09 (1.07-4.08)). Other predictors associated with dementia included older age, higher prestroke morbidity (mRS), WMLs, and GA. Integrated in a prediction model with clinical parameters, prestroke mRS, cardiovascular disease, GA, MTA and Abbreviated-Mental-Test were the strongest predictors of dementia (c-statistic: 0.77).

DISCUSSION AND CONCLUSION

Increased brain-frailty, and its individual components (WMLs, MTA, and GA) are associated with a higher risk of dementia in participants with stroke. Combining clinical and brain-frailty parameters created a moderate dementia prediction model but added little value over clinical parameters in combination with cognitive testing. CT-based brain-frailty may provide better prognostic insights when cognitive testing isn't feasible and for identifying highest-risk individuals for dementia prevention trials to increase trial efficiency.

The relative associations of aortic and carotid artery stiffness with CeVD and cognition

We examined the relative associations of aortic and carotid artery stiffness with cerebrovascular disease (CeVD), cognition, and dementia subtypes in a memory clinic cohort of 272 participants (mean age = 75.4, SD = 6.8). We hypothesized that carotid artery stiffness would have greater effects on outcomes, given its proximate relationship to the brain. Aortic and carotid artery stiffness were assessed with applanation tonometry and carotid ultrasonography, respectively. CeVD markers included white matter hyperintensities (WMH), lacunes, cerebral microbleeds, cortical infarcts, and intracranial stenosis. Cognition was assessed by the Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and a neuropsychological battery. Multivariable linear regression was conducted to determine associations of arterial stiffness with WMH and cognition, while logistic regression analysed associations with CeVD markers and dementia subtypes. Carotid artery stiffness z-score was associated with WMH, cortical infarcts, vascular cognitive impairment, and MMSE, independent of age, sex, education, vascular risk factors, and aortic stiffness z-score. Although aortic stiffness z-score was independently associated with cortical infarcts, this became non-significant after further adjusting for carotid artery stiffness z-score. We found that carotid artery stiffness had greater effects on CeVD, cognitive function and impairment in memory clinic patients compared to aortic stiffness.

Sex differences in the association of Alzheimer's disease biomarkers and cognition in a multicenter memory clinic study

BACKGROUND

This study investigated sex differences in the associations between Alzheimer's disease (AD) biomarkers, cognitive performance, and decline in memory clinic settings.

METHODS

249 participants (females/males:123/126), who underwent tau-PET, amyloid-PET, structural MRI, and plasma glial fibrillary acidic protein (GFAP) measurement were included from Geneva and Lausanne Memory Clinics. Mann-Whitney U tests investigated sex differences in clinical and biomarker data. Linear regression models estimated the moderating effect of sex on the relationship between biomarkers and cognitive performance and decline. Sex differences in cognitive decline were further evaluated using longitudinal linear mixed-effect models with three-way interaction effects.

RESULTS

Women and men present similar clinical features, amyloid, and neurodegeneration. Women had higher tau load and plasma levels of GFAP than men (p < 0.05). Tau associations with amyloid (standardized β = 0.54,p < 0.001), neurodegeneration (standardized β=-0.44,p < 0.001), and cognition (standardized β=-0.48,p < 0.001) were moderated by a significant interaction with sex. Specifically, the association between amyloid and tau was stronger among women than men (standardized β=-0.19,p = 0.047), whereas the associations between tau and cognition and between tau and neurodegeneration were stronger among men than in women (standardized β=-0.76,p = 0.001 and standardized β=-0.56,p = 0.044). Women exhibited faster cognitive decline than men in the presence of severe cortical thinning (p < 0.001).

CONCLUSION

Women showed higher tau load and stronger association between amyloid and tau than men. In individuals with high tau burden, men exhibited greater neurodegeneration and cognitive impairment than women. These findings support that sex differences may impact tau deposition through an upstream interplay with amyloid, leading to downstream effects on neurodegeneration and cognitive outcomes.

Exploring cognitive and neuroimaging profiles of dementia subtypes of individuals with dementia in the Democratic Republic of Congo

Objective

The 2024 Alzheimer's Association (AA) research diagnostic criteria for Alzheimer's Disease (AD) considers fluid biomarkers, including promising blood-based biomarkers for detecting AD. This study aims to identify dementia subtypes and their cognitive and neuroimaging profiles in older adults with dementia in the Democratic Republic of Congo (DRC) using biomarkers and clinical data.

Methods

Forty-five individuals with dementia over 65 years old were evaluated using the Community Screening Instrument for Dementia and the informant-based Alzheimer's Questionnaire. Core AD biomarkers (Aβ42/40 and p-tau181) and non-specific neurodegeneration biomarkers (NfL, GFAP) were measured in blood plasma. Neuroimaging structures were assessed using magnetic resonance imaging (MRI). Dementia subtypes were determined based on plasma biomarker pathology and vascular markers. Biomarker cutoff scores were identified to optimize sensitivity and specificity. Individuals were stratified into one of four dementia subtypes-AD only, non-AD vascular, non-AD other, or mixed - based on combinations of abnormalities in these markers.

Results

Among the 45 individuals with dementia, mixed dementia had the highest prevalence (42.4%), followed by AD-only (24.4%), non-AD other dementia (22.2%), and non-AD vascular dementia subtypes (11.1%). Both cognitive and neuroimaging profiles aligned poorly with biomarker classifications in the full sample. Cognitive tests varied across dementia subtypes. The cognitive profile of the AD-only and mixed groups suggested relatively low cognitive performance, while the non-AD and other groups had the best scores on average.

Conclusion

Consistent with studies in other settings, our preliminary findings suggest that neurodegenerative plasma biomarkers may help to identify dementia subtypes and provide insight into cognitive and neuroimaging profiles among older adults in the DRC.

Middle-age cerebral small vessel disease and cognitive function in later life: a population-based prospective cohort study

Background

Cerebral small vessel disease (cSVD) is a major pathologic substrate of vascular contribution to cognitive impairment. However, population based long-term longitudinal cognitive function data in relation to cSVD are rare. We investigated the relationship between cSVD and cognitive decline over time in middle-aged through elderly population.

Methods

This prospective cohort study was conducted in a community-based adult population (avg. age 58.5 ± 6.4) who underwent both magnetic resonance imaging (MRI) and comprehensive neuropsychological tests at baseline (2011-2014). The participants were followed-up with the same neuropsychological test battery 4-yearly in two more cycles (in 2015-2018 and 2019-2022). A total of 2454 participants who were free of dementia and cerebrovascular disease at baseline with cognitive function testing at least 2 time points over the time were analyzed. Data analysis was performed from May 1, 2023 to January 31, 2024. SVD was defined by the presence of any of the visible MRI markers (age-related white matter change, lacunes and cerebral microbleeds) at baseline. The main outcomes were multivariable adjusted mean differences of cognitive test performances by cSVD groups over time. The neuropsychological assessment battery included verbal and visual memory, verbal fluency, Digit Symbol-coding, Trail Making Test-A, and Stroop Test. To examine the relationship between cSVD and cognitive function, we used linear mixed model for repeated measurements to compare the means (95% CIs) by cSVD groups.

Findings

Of the total, 908 (37.0%) participants had cSVD on MRI reading at baseline. By location, cSVD were mostly found in the frontal lobe followed by basal ganglia area of the brain. None of the cognitive test scores, except Trail Making Test-A, were significantly different between the cSVD groups at baseline. At 8-year follow-up, participants without cSVD performed significantly better than participants with cSVD in Stroop-color reading [Mean difference 1.19 (95% CI: 0.02-2.36), p = 0.0451] and visual reproduction-recognition [Mean difference 0.11 (95% CI: 0.01-0.21), p = 0.0221]. While no other cognitive tests showed any differential changes by cSVD groups, logical memory (Story Recall Tests) increased and Stroop-word reading decreased over time in both cSVD groups almost identically.

Interpretation

Silent cSVD was independently associated with decline in executive functioning over 8-year follow-up period in this Korean middle-aged through elderly general population. Future studies considering wider spectrum of cSVD and longer follow-up durations may help predict further cognitive outcomes.

Funding

This study was funded by the Korea Centers for Disease Control and Prevention.

Cognitive profile in burning mouth syndrome versus mild cognitive impairment: A comparative study

OBJECTIVES

This study aims to assess and contrast cognitive and psychological aspects of patients with burning mouth syndrome (BMS-MCI) and geriatric patients (G-MCI) with mild cognitive impairment, focusing on potential predictors like pain, mood disorders, blood biomarkers, and age-related white matter changes (ARWMCs).

METHODS

The study enrolled 40 BMS-MCI and 40 geriatric G-MCI, matching them by age, gender, and educational background. Participants underwent psychological, sleepiness, and cognitive assessment including the Mini-Mental State Exam (MMSE), Trail Making Test (TMT), Corsi Block-Tapping Task, Rey Auditory Verbal Learning Test, Copying Geometric Drawings Test, Frontal Assessment Battery, and Digit Cancellation Test.

RESULTS

G-MCI patients exhibited higher ARWMCs scores in right (p = 0.005**) and left (p < 0.001**) temporal regions, which may relate to specific neurodegenerative processes. Conversely, BMS-MCI patients showed higher levels of depression and anxiety and lower MMSE scores(p < 0.001**), also struggling more with tasks requiring processing speed and executive function, as evidenced by their higher TMT-A scores (p < 0.001**).

CONCLUSIONS

The study highlights particular deficits in global cognition and processing speed for BMS-MCI. The influence of educational background, pain levels, cholesterol, sleep disturbances, and anxiety on these cognitive assessments underscores the need for personalized therapeutic strategies addressing both cognitive and emotional aspects of MCI.

Methods for assessment of Rey Auditory Verbal Learning Test performance in memory clinic patients and healthy adults - at the cross-roads of learning theory and clinical utility

Background: Knowledge is still lacking regarding the preferred method for evaluation of learning in the Rey Auditory Verbal Learning Test (RAVLT). Validity of different methods was examined by the effect size in differentiating diagnostic stages in memory clinic patients versus healthy adults and the strength of association between RAVLT performance and brain atrophy. Method: The study included individuals with dementia (n = 247), Mild Cognitive Impairment (MCI, n = 709), Subjective Cognitive Impairment (SCI, n = 175) and cognitively unimpaired adults serving as healthy controls (HC, n = 102). All patients went through a comprehensive clinical examination and neuropsychological assessment of cognition including episodic memory gauged with RAVLT and brain imaging of medial temporal atrophy, cortical atrophy, and white matter hyperintensity. Results: The standard method for evaluation of learning in RAVLT (summed score over five trials) together with the late learning method (mean of trials 4 and 5) were the two most powerful methods according to group differentiation (discriminant validity). Both methods also showed considerable association with medial temporal atrophy (construct validity). The initial RAVLT performance represented by results on trial 1 and the constant in regression analysis with the power function provided information regarding attention that was important for the separation of SCI and HC. Conclusions: The most favorable clinical utility was indicated by discriminant and construct validity by total learning (standard method) including both attention- and learning-related parts and late learning of RAVLT performance, while theoretical understanding of mental processes involved in RAVLT performance was provided by the distinction between initial versus the subsequent learning performance.

Investigation of Hemorheological Parameters in Ischemic Stroke Patients

BACKGROUND

The aim of this study is to determine whether there are any changes in hemorheological parameters, including whole blood viscosity (WBV), plasma viscosity, erythrocyte aggregation, and erythrocyte deformability, in acute ischemic stroke patients, and to establish their relationship with stroke etiology. The study also aims to observe the changes in these parameters, if any, over time and after treatment, and to assess the correlation between risk factors for ischemic stroke and neuroimaging findings.

METHODS

This was a prospective observational study including 70 patients diagnosed with acute ischemic stroke within the first 3 days of the onset of symptoms and 96 healthy controls. Stroke patients were categorized based on TOAST criteria, and hemorheological parameters were measured at admission and on the fifth day post-treatment. Erythrocyte aggregation and deformability were measured using a laser ektacytometer, and viscosity assessment was conducted with a rotational viscometer.

RESULTS

Stroke patients exhibited significant differences from the control group in aggregation amplitude, aggregation index, and aggregation half-time (p = 0.001, p = 0.013, p = 0.009, respectively) and showed elevated maximum value of elongation index (p = 0.000). No significant differences in WBV and plasma viscosity were observed between the groups. Post-treatment, the small vessel occlusion subgroup demonstrated a notable reduction in WBV. Additionally, homocysteine levels showed a positive correlation with scattered white matter lesions in basal ganglia and infratentorial regions (p = 0.002, p = 0.039, respectively).

CONCLUSIONS

Increased predisposition to erythrocyte aggregation may contribute to the occurrence of acute ischemic stroke. Moreover, gaining the ability of erythrocytes to deform and increase blood flow may serve as a compensatory mechanism in the chronic vascular disease process. The risk factors for ischemic stroke may exhibit connections to specific areas within the brain.

Identifying sources of bias when testing three available algorithms for quantifying white matter lesions: BIANCA, LPA and LGA

Brain magnetic resonance imaging frequently reveals white matter lesions (WMLs) in older adults. They are often associated with cognitive impairment and risk of dementia. Given the continuous search for the optimal segmentation algorithm, we broke down this question by exploring whether the output of algorithms frequently used might be biased by the presence of different influencing factors. We studied the impact of age, sex, blood glucose levels, diabetes, systolic blood pressure and hypertension on automatic WML segmentation algorithms. We evaluated three widely used algorithms (BIANCA, LPA and LGA) using the population-based 1000BRAINS cohort (N = 1166, aged 18-87, 523 females, 643 males). We analysed two main aspects. Firstly, we examined whether training data (TD) characteristics influenced WML estimations, assessing the impact of relevant factors in the TD. Secondly, algorithm's output and performance within selected subgroups defined by these factors were assessed. Results revealed that BIANCA's WML estimations are influenced by the characteristics present in the TD. LPA and LGA consistently provided lower WML estimations compared to BIANCA's output when tested on participants under 67 years of age without risk cardiovascular factors. Notably, LPA and LGA showed reduced accuracy for these participants. However, LPA and LGA showed better performance for older participants presenting cardiovascular risk factors. Results suggest that incorporating comprehensive cohort factors like diverse age, sex and participants with and without hypertension in the TD could enhance WML-based analyses and mitigate potential sources of bias. LPA and LGA are a fast and valid option for older participants with cardiovascular risk factors.

The added value of b0-DWI analysis in the diagnosis of cavitating lacunes when T2-weighted spin-echo is unavailable

PURPOSE

Silent brain infarcts, sometimes appearing as incidental lacunes in patients with unknown history of vascular event, are linked to dementia, gait disturbances and depression. We observed that some cavitating lacunes were only visible on b0-diffusion-weighted-imaging (b0-DWI: T2-weighted without diffusion gradients) when T2-weighted-spin-echo (T2-SE) was unavailable. We aimed to evaluate the additional value of b0-DWI in detecting cavitating lacunes.

METHODS

We retrospectively included patients aged ≥ 65 years who underwent brain MRI (1.5 T or 3 T) for various indications, with FLAIR (Fluid Attenuated Inversion Recovery) and b0-DWI, without T2-SE. Patients with multiple sclerosis, lacking b0-DWI or with low-quality MRI were excluded. Vascular risk factors, white matter lesions (Fazekas scale) and mention of lacune in the radiology report were inquired. Two radiologists independently analyzed all b0-DWI sequences, followed by FLAIR.

RESULTS

Among 306 subjects, at least one lacune was observed in 149 (48.7 %): 54 (36.2 %) supratentorial, 32 (21.5 %) infratentorial and 63 (42.3 %) both. Of these, 119 (79.9 %) had vascular risk factors and 135 (90.6 %) had white matter lesions. 33 (10.8 %) were exclusively detected on b0-DWI (b0-DWI-lacunes), of which 5 (1.6 %) without vascular factor, and 20 (6.5 %) were unmentioned in the report. Among b0-DWI-lacunes, 15 (45.5 %) were supratentorial, 9 (27.3 %) infratentorial and 9 (27.3 %) both, with 28 (84.8 %) associated with white matter lesions. Inter-rater reliability for b0-DWI-lacunes diagnosis was good (95.6 % agreement, kappa = 0.717, CI95% [0.568-0.869]).

CONCLUSION

In our study, 10.8% b0-DWI-lacunes were not visible on FLAIR, and 6.5% were unmentioned in the neuroradiology report. Examining FLAIR alongside b0-DWI improves diagnostic performance for cavitating lacune detection and contributes to vascular prevention.

Predicting Long-Term Outcome of Prolonged Disorder of Consciousness in Children Through Machine Learning Based on Conventional Structural Magnetic Resonance Imaging

BACKGROUND

The prognosis of prolonged disorders of consciousness (pDoC) in children has consistently posed a formidable challenge in clinical decision-making.

OBJECTIVE

This study aimed to develop a machine learning (ML) model based on conventional structural magnetic resonance imaging (csMRI) to predict outcomes in children with pDoC.

METHODS

A total of 196 children with pDoC were included in this study. Based on the consciousness states 1 year after brain injury, the children were categorized into either the favorable prognosis group or the poor prognosis group. They were then randomly assigned to the training set (n = 138) or the test set (n = 58). Semi-quantitative visual assessments of brain csMRI were conducted and Least Absolute Shrinkage and Selection Operator regression was used to identify significant features predicting outcomes. Based on the selected features, support vector machine (SVM), random forests (RF), and logistic regression (LR) were used to develop csMRI, clinical, and csMRI-clinical-merge models, respectively. Finally, the performances of all models were evaluated.

RESULTS

Seven csMRI features and 4 clinical features were identified as important predictors of consciousness recovery. All models achieved satisfactory prognostic performances (all areas under the curve [AUCs] >0.70). Notably, the csMRI model developed using the SVM exhibited the best performance, with an AUC, accuracy, sensitivity, and specificity of 0.851, 0.845, 0.844, and 0.846, respectively.

CONCLUSIONS

A csMRI-based prediction model for the prognosis of children with pDoC was developed, showing potential to predict recovery of consciousness 1 year after brain injury and is worth popularizing in clinical practice.

Altered brain functional network connectivity and topology in type 2 diabetes mellitus

Introduction

Type 2 diabetes mellitus (T2DM) accelerates brain aging and disrupts brain functional network connectivity, though the specific mechanisms remain unclear. This study aimed to investigate T2DM-driven alterations in brain functional network connectivity and topology.

Methods

Eighty-five T2DM patients and 67 healthy controls (HCs) were included. All participants underwent clinical, neuropsychological, and laboratory tests, followed by MRI examinations, including resting-state functional magnetic resonance imaging (rs-fMRI) and three-dimensional high-resolution T1-weighted imaging (3D-T1WI) on a 3.0 T MRI scanner. Post-image preprocessing, brain functional networks were constructed using the Dosenbach atlas and analyzed with the DPABI-NET toolkit through graph theory.

Results

In T2DM patients, functional connectivity within and between the default mode network (DMN), frontal parietal network (FPN), subcortical network (SCN), ventral attention network (VAN), somatosensory network (SMN), and visual network (VN) was significantly reduced compared to HCs. Conversely, two functional connections within the VN and between the DMN and SMN were significantly increased. Global network topology analysis showed an increased shortest path length and decreased clustering coefficient, global efficiency, and local efficiency in the T2DM group. MoCA scores were negatively correlated with the shortest path length and positively correlated with global and local efficiency in the T2DM group. Node network topology analysis indicated reduced clustering coefficient, degree centrality, eigenvector centrality, and nodal efficiency in multiple nodes in the T2DM group. MoCA scores positively correlated with clustering coefficient and nodal efficiency in the bilateral precentral gyrus in the T2DM group.

Discussion

This study demonstrated significant abnormalities in connectivity and topology of large-scale brain functional networks in T2DM patients. These findings suggest that brain functional network connectivity and topology could serve as imaging biomarkers, providing insights into the underlying neuropathological processes associated with T2DM-related cognitive impairment.

Associations of inferior frontal sulcal hyperintensities on brain MRI with cerebral small vessel disease, cognitive function, and depression symptoms

Inferior frontal sulcal hyperintensities (IFSH) observed on fluid-attenuated inversion recovery (FLAIR) MRI have been proposed as indicators of elevated cerebrospinal fluid waste accumulation in cerebral small vessel disease (CSVD). However, to validate IFSH as a reliable imaging biomarker, further replication studies are required. The objective of this study was to investigate associations between IFSH and CSVD, and their potential repercussions, i.e., cognitive impairment and depression. We prospectively recruited 47 patients with CSVD and 29 cognitively normal controls (NC). IFSH were rated visually based on FLAIR MRI. Using different regression models, we explored the relationship between IFSH, group status (CSVD vs. NC), CSVD severity assessed with MRI, cognitive function, and symptoms of depression. Patients with CSVD were more likely to have higher IFSH scores compared to NC (OR 5.64, 95% CI 1.91-16.60), and greater CSVD severity on MRI predicted more severe IFSH (OR 1.47, 95% CI 1.14-1.88). Higher IFSH scores were associated with lower cognitive function (-0.96, 95% CI -1.81 to -0.10), and higher levels of depression (0.33, 95% CI 0.01-0.65). CSVD and IFSH may be tightly linked to each other, and the accumulation of waste products, indicated by IFSH, could have detrimental effects on cognitive function and symptoms of depression.

AI-Assisted Compressed Sensing Enables Faster Brain MRI for the Elderly: Image Quality and Diagnostic Equivalence with Conventional Imaging

Purpose

Conventional brain MRI protocols are time-consuming, which can lead to patient discomfort and inefficiency in clinical settings. This study aims to assess the feasibility of using artificial intelligence-assisted compressed sensing (ACS) to reduce brain MRI scan time while maintaining image quality and diagnostic accuracy compared to a conventional imaging protocol.

Patients and Methods

Seventy patients from the department of neurology underwent brain MRI scans using both conventional and ACS protocols, including axial and sagittal T2-weighted fast spin-echo sequences and T2-fluid attenuated inversion recovery (FLAIR) sequence. Two radiologists independently evaluated image quality based on avoidance of artifacts, boundary sharpness, visibility of lesions, and overall image quality using a 5-point Likert scale. Pathological features, including white matter hyperintensities, lacunar infarcts, and enlarged perivascular spaces, were also assessed. The interchangeability of the two protocols was determined by calculating the 95% confidence interval (CI) for the individual equivalence index. Additionally, Cohen's weighted kappa statistic was used to assess inter-protocol intra-observer agreement.

Results

The ACS images demonstrated superior quality across all qualitative features compared to the conventional ones. Both protocols showed no significant difference in detecting pathological conditions. The 95% CI for the individual equivalence index was below 5% for all variables except enlarged perivascular spaces, indicating the interchangeability of the conventional and ACS protocols in most cases. The inter-rater reliability between the two radiologists was strong, with kappa values of 0.78, 0.74, 0.70 and 0.86 for image quality evaluation and 0.74, 0.80 and 0.70 for diagnostic performance, indicating good-to-excellent agreement in their evaluations.

Conclusion

The ACS technique reduces brain MRI scan time by 29.2% while achieving higher image quality and equivalent diagnostic accuracy compared to the conventional protocol. This suggests that ACS could be potentially adopted for routine clinical use in brain MRI.

A Comparison of the Brain Parameters of Thais with Normal Cognition, Mild Cognitive Impairment, and Dementia

OBJECTIVES

This study examined the differences in brain volume and cortical thickness among individuals with normal cognition (NC) and those with NCDs, including mild cognitive impairment (MCI) and dementia. The aim was to identify the brain parameters supporting clinical decision-making for NCDs.

METHOD

A total of 116 participants were categorized into dementia, MCI, and NC groups, and their brain scans using structural magnetic resonance imaging (MRI) were processed and automatedly analyzed with FreeSurfer to obtain the absolute brain volume, volume normalized by intracranial volume (ICV), and cortical thickness. Patients with dementia exhibited a significantly smaller brain volume and cortical thickness than the MCI and NC groups.

RESULTS

The left amygdala/ICV ratio demonstrated excellent performance in diagnosing early NCDs, with a cutpoint of ≤0.089, providing 83.30% sensitivity, 84.20% specificity, and 83.82% accuracy. For MCI, a cutpoint of ≤0.099 for the left amygdala/ICV yielded 96.70% sensitivity, 83.30% specificity, and 88.46% accuracy.

CONCLUSIONS

The findings suggested that reductions in brain volume and cortical thickness correlate with cognitive decline. Utilizing FreeSurfer and MRI data, particularly the left amygdala/ICV ratio, may serve as a valuable biomarker for the early identification of individuals at risk for developing NCDs.

Functional Connectivity and MRI Radiomics Biomarkers of Cognitive and Brain Reserve in Post-Stroke Cognitive Impairment Prediction-A Study Protocol

Acute ischemic stroke (AIS) is frequently associated with long-term post-stroke cognitive impairment (PSCI) and dementia. While the mechanisms behind PSCI are not fully understood, the brain and cognitive reserve concepts are topics of ongoing research exploring the ability of individuals to maintain intact cognitive performance despite ischemic injuries. Brain reserve refers to the brain's structural capacity to compensate for damage, with markers like hippocampal atrophy and white matter lesions indicating reduced reserve. Cognitive reserve involves the brain's ability to optimize performance and use alternative networks to maintain function. Advanced methods of MRI and EEG processing may better assess brain reserve and cognitive reserve, with emerging predictive models integrating these measures to improve PSCI prediction. This article provides the design of a hospital-based study investigating the predictive role of functional connectivity and MRI radiomics in assessing PSCI occurrence one year after AIS. One hundred forty-four patients will be enrolled following strict inclusion/exclusion criteria. The patients will undergo comprehensive assessments, including neuropsychological testing, brain MRI, and quantitative EEG (QEEG), across four visits over a year. The primary outcome will be PSCI occurrence, and it will be assessed at six and twelve months after AIS. Secondary outcomes will include PSCI severity, recurrent AIS, and mortality. Statistical analyses will be performed to identify predictive factors using Cox proportional hazards models, and predictive models based on QEEG, MRI radiomics, and clinical data will be built. Early detection of AIS patients prone to developing PSCI might outline more effective therapeutic approaches, reducing the social and economic burden of ischemic stroke.

Neuropsychiatric symptoms and specific cognitive domains in mild cognitive impairment

Neuropsychiatric symptoms (NPS) such as depression, anxiety, and apathy are present in mild cognitive impairment (MCI) and are risk factors for cognitive decline. However, the relationship between NPS and specific cognitive domains is less clear.

Objective

This study aimed to assess whether there is a correlation between NPS and specific cognitive domains.

Methods

A cross-sectional study which included 174 participants with MCI, aged 55 years or older. Differences in sociodemographic profile, neuroimaging, and neuropsychological tests between MCI participants with and without NPS were measured.

Results

Participants with NPS had lower education and worse performance in attention tests and executive functions. Psychotic symptoms were correlated with deficits in visuospatial functions; irritability and agitation with inattention and deficit of inhibitory control; and depression with inattention.

Conclusion

Correlations were found between some NPS with specific cognitive domains, especially psychotic symptoms, but also agitation, irritability, apathy, and depression.

Statin therapy in ischemic stroke patients with atrial fibrillation: Efficacy and safety outcomes

INTRODUCTION

The efficacy and safety of statins for secondary prevention in patients who have experienced a cardioembolic stroke are not well-defined. However, previous observational data reported hyperlipidemia as a risk factor for both ischemic and bleeding complications in patients with AF and previous stroke. Based on these premises, we conducted a sub-analysis of the RAF and RAF-NOAC studies to evaluate the efficacy and safety of statins in secondary prevention in patients with acute ischemic stroke and AF.

MATERIALS AND METHODS

We combined patient data from the RAF and RAF-NOAC studies, prospective observational studies conducted across Stroke Units in Europe, the United States, and Asia from January 2012 to June 2016. We included consecutive patients with AF who suffered an acute ischemic stroke with a follow-up of 90 days. Our outcomes were the combined endpoint, including stroke, transient ischemic attack, systemic embolism, symptomatic intracerebral hemorrhage, and major extracranial bleeding. Furthermore, both ischemic and hemorrhagic outcomes were evaluated separately.

RESULTS

A total of 1742 patients were included (46% male), and 898 (52%) received statins after the index event, of whom 436 (48.6%) were already taking statins before the index event, 462 (51.4%) started treatment after. At multivariable analysis, statin use was statistically associated with age (OR 0.92, 95% CI 0.97-0.99, p = 0.001), male sex (OR 1.35, 95% CI 1.07-1.70, p = 0.013), anticoagulation (OR 2.53, 95% CI 1.90-3.36, p < 0.0001), hyperlipidemia (OR 5.52, 95% CI 4.28-7.12, p < 0.0001), paroxysmal AF (OR 1.40, 95% CI 1.12-1.75, p = 0.003), leukoaraiosis (OR 1.39, 95% CI 1.11-1.75, p = 0.004) and heart failure (OR 0.72, 95% CI 0.53-0.98, p = 0.034). Statin use was not associated with the combined outcome event (OR 0.84, 95% CI 0.58-1.23, p = 0.3) and ischemic outcome event (OR 1.17, 95% CI 0.73-1.88, p = 0.5) while was associated with a lower risk of hemorrhagic outcome event (OR 0.51, 95% CI 0.28-0.91, p = 0.02).

DISCUSSION

Statins protect cerebral arterial vessels (particularly small vessels) from subacute damage due to hypertension, diabetes, and other harmful agents (such as reactive oxygen species, proinflammatory cytokines, etc.) due to their systemic anti-inflammatory and endothelium-protective effects.

CONCLUSIONS

Our data show that statins seem to protect against global bleeding events in cardioembolic stroke patients; this may be due to the pleiotropic effect of statins. More data are warranted to confirm these findings.

evoke and evoke+: design of two large-scale, double-blind, placebo-controlled, phase 3 studies evaluating efficacy, safety, and tolerability of semaglutide in early-stage symptomatic Alzheimer's disease

BACKGROUND

Disease-modifying therapies targeting the diverse pathophysiology of Alzheimer's disease (AD), including neuroinflammation, represent potentially important and novel approaches. The glucagon-like peptide-1 receptor agonist semaglutide is approved for the treatment of type 2 diabetes and obesity and has an established safety profile. Semaglutide may have a disease-modifying, neuroprotective effect in AD through multimodal mechanisms including neuroinflammatory, vascular, and other AD-related processes. Large randomized controlled trials are needed to assess the efficacy and safety of semaglutide in early-stage symptomatic AD.

METHODS

evoke and evoke+ are randomized, double-blind, placebo-controlled phase 3 trials investigating the efficacy, safety, and tolerability of once-daily oral semaglutide versus placebo in early-stage symptomatic AD. Eligible participants were men or women aged 55-85 years with mild cognitive impairment or mild dementia due to AD with confirmed amyloid abnormalities (assessed by positron emission tomography or cerebrospinal fluid [CSF] analysis). After a maximum 12-week screening phase, an anticipated 1840 patients in each trial are randomized (1:1) to semaglutide or placebo for 156 weeks (104-week main treatment phase and 52-week extension). Randomized participants follow an 8-week dose escalation regimen (3 mg [weeks 0-4], 7 mg [weeks 4-8], and 14 mg [weeks 8-156]). The primary endpoint is the semaglutide-placebo difference on change from baseline to week 104 in the Clinical Dementia Rating - Sum of Boxes score. Analyses of plasma biomarkers, collected from all participants, and a CSF sub-study (planned n = 210) will explore semaglutide effects on AD biomarkers and neuroinflammation.

RESULTS

Enrollment was undertaken between May 18, 2021, and September 8, 2023. Completion of the trials' main phase is expected in September 2025, and the 52-week extension (in which participants and investigators remain blinded to treatment assignment) will continue to October 2026.

CONCLUSION

evoke and evoke+ are the first large-scale trials to investigate the disease-modifying potential of semaglutide in participants with early-stage symptomatic AD, including exploration of effects on AD biomarkers and neuroinflammation. The trials will provide data on the potential disease-modifying effects of semaglutide and will be important in evaluating its utility in the treatment of early-stage symptomatic AD.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04777396 and NCT04777409. Date: 02/03/2021.

Late-onset temporal lobe epilepsy: insights from brain atrophy and Alzheimer's disease biomarkers

Considering the growing age of the world population, the incidence of epilepsy in older adults is expected to increase significantly. It has been suggested that late-onset temporal lobe epilepsy (LO-TLE) may be neurodegenerative in origin and overlap with Alzheimer's disease (AD). Herein, we aimed to characterize the pattern of cortical atrophy and CSF biomarkers of AD (total and phosphorylated tau and amyloid-β) in a selected population of LO-TLE of unknown origin. We prospectively enrolled individuals with temporal lobe epilepsy onset after the age of 50 and no cognitive impairment. They underwent a structural MRI scan and CSF biomarkers measurement. Imaging and biomarkers data were compared to three retrospectively collected groups: (i) age-sex-matched healthy controls; (ii) patients with mild cognitive impairment (MCI) and abnormal CSF AD biomarkers (MCI-AD); and (iii) patients with MCI and normal CSF AD biomarkers (MCI-noAD). From a pool of 52 patients, 20 consecutive eligible LO-TLE patients with a mean disease duration of 1.8 years were recruited. As control populations, 25 patients with MCI-AD, 25 patients with MCI-noAD and 25 healthy controls were enrolled. CSF biomarkers returned normal values in LO-TLE, significantly different from patients with MCI due to AD. There were no differences in cortico-subcortical atrophy between epilepsy patients and healthy controls, while patients with MCI demonstrated widespread injuries of cortico-subcortical structures. Individuals with LO-TLE, characterized by short disease duration and normal CSF amyloid-β and tau protein levels, showed patterns of cortical thickness and subcortical volumes not significantly different from healthy controls, but highly different from patients with MCI, either due to AD or not.

Hyperconnectivity in resting-state fMRI as a marker of disease severity in Myotonic Dystrophy Type 1

INTRODUCTION

Myotonic dystrophy type 1 (DM1) patients show both structural and functional brain alterations, including abnormal resting-state (RS) functional connectivity. Although some studies have investigated RS functional connectivity in DM1, methodological differences make it challenging to draw consistent conclusions.

OBJECTIVES

This study aims to analyze 1) RS functional connectivity in DM1 patients compared to healthy controls (HC), 2) graph theory metrics, 3) longitudinal connectivity variations, and 4) the relationship between connectivity and clinical, cognitive, and structural brain data.

METHODOLOGY

Twenty-one DM1 patients and 21 matched HCs underwent 3 T MRI scans, including RS fMRI. Of these, 15 DM1 patients and 13 HCs participated in the follow-up after 3 years. Additionally, DM1 patients underwent baseline clinical, molecular and cognitive assessments. Functional connectivity analysis (ROI-to-ROI) and graph theory measures were employed. Longitudinal changes in connectivity were examined, and total hyperconnectivity and hypoconnectivity values were calculated to explore correlations with clinical, brain, and cognitive correlates.

RESULTS

DM1 patients showed widespread hyperconnectivity compared to HCs. Although no statistically significant differences were found in graph theory measures, patients tended to show decreased efficiency, strength, and clustering (with moderate effect sizes). Patients remained hyperconnected over time, with a progression similar to HCs. Hyperconnectivity was associated with more severe disease, greater muscular impairment, and molecular defects, as well as lower cognitive performance. Conversely, hypoconnectivity was associated with less severe disease.

DISCUSSION

DM1 patients are characterized by brain hyperconnectivity and a less efficient brain network organization. Hyperconnectivity is discussed as a compensatory mechanism and is suggested as a disease severity marker.

Vascular Neurology Considerations for Antiamyloid Immunotherapy: A Science Advisory From the American Heart Association

Antibodies directed at the amyloid-β peptide offer the prospect of disease-modifying therapy for early-stage Alzheimer disease but also carry the risk of brain edema or bleeding events, collectively designated amyloid-related imaging abnormalities. Introduction of the antiamyloid immunotherapies into practice is therefore likely to present a new set of questions for clinicians treating patients with cerebrovascular disease: Which manifestations of cerebrovascular disease should preclude, or permit, antibody treatment? Is it safe to prescribe amyloid immunotherapies to individuals who require antithrombotic treatment, or to administer thrombolysis to antibody-treated individuals with acute stroke? How should severe amyloid-related imaging abnormalities be managed? This science advisory summarizes the data and key considerations to guide these challenging decisions as the medical community collects further data and experience with these groundbreaking agents.

Volume and distribution of white matter hyperintensities in rheumatoid arthritis and ulcerative colitis patients

Brain white matter disruptions have been implicated in contributing to fatigue, brain fog and other central symptoms commonly reported in inflammatory diseases. In this study, we included 252 RA patients with 756 age and sex matched controls and 240 UC patients with 720 age and sex matched controls using the UK Biobank imaging dataset. We looked for differences in total volume of white matter hyperintensities (WMH) between patients compared to controls. Then, using voxelwise analysis, we explored the spatial distribution of these white matter hyperintensities and differences in these between patients and controls and between disease groups. A significantly higher volume of WMH was observed in both the RA (p = 1.9 × 10-8, β =  - 0.36, 95% CI =  - 0.48, - 0.23) and UC (p = 0.003, β =  - 0.18 95% CI =  - 0.31, - 0.06) patients compared to their respective control groups. Voxelwise analysis revealed only a small cluster of RA associated WMH compared to controls. These results indicate an increased risk of white matter hyperintensities in patients with RA and UC. These findings help quantify the effect of inflammation from autoimmune diseases on cerebrovascular health and white matter integrity.

Hypertension and Cognitive Disorders

Systemic hypertension is possibly the most important modifiable risk factor for the development of cognitive decline, both for mild cognitive impairment (MCI) and dementia. For effective blood pressure (BP) control, it requires proper assessment, using brachial, central, and ambulatory measurements, and monitoring with a focus on different BP parameters. Different BP parameters like pulse pressure, mean arterial pressure, BP variability, and circadian parameters, like nondippers and early morning surge, should be considered in the evaluation for the risk of cognitive decline due to hypertension in middle age and older adults. Chronic hypertension causes vascular remodeling in the brain and leads to brain failure or cognitive decline. Achieving specific BP goals can improve clinical outcomes and possibly slow down cognitive decline for patients with comorbid hypertension and cognitive impairment.