Association of white matter lesions and lacunar infarcts with executive functioning: the SMART-MR study

Cerebral arteriolosclerosis, lacunar infarcts, and cognition in older Black adults

INTRODUCTION

Older Black adults are at risk of cerebral small vessel disease (CSVD), which contributes to dementia risk. Two subtypes of CSVD, arteriolosclerosis and ischemic lacunar infarcts, have been independently linked to lower cognition and higher dementia risk, but their combined effects on cognition in older Black adults are unclear.

METHODS

Mixed models were used to examine the associations of in vivo measures of arteriolosclerosis (ARTS) and ischemic lacunar infarcts to cognitive level and change in 370 older Black adults without dementia.  RESULTS: Modeled together, higher ARTS load accounted for lower levels of global cognition, episodic memory, semantic memory, and perceptual speed, whereas higher infarct load accounted for lower levels of working memory. There were no associations with rate of cognitive change.

DISCUSSION

Both arteriolosclerosis and ischemic infarcts impact the cognitive health of older Black adults, but arteriolosclerosis affects cognition more broadly and offers promise as an in vivo biomarker of dementia risk.

HIGHLIGHTS

Older Black adults are at risk of cerebral small vessel disease (CSVD) and dementia. Examined magnetic resonance imaging-derived measure of arteriolosclerosis (ARTS), infarcts, and cognition. ARTS load was widely associated with lower cognition after adjusting for infarct load. Infarct load was specifically associated with lower complex attention. More within-Black in vivo studies of CSVD subtypes and cognition are needed.

Bear in mind: the role of personal background in semantic animal fluency - The SMART-MR study

Objectives

Semantic fluency is a prominent neuropsychological task, typically administered within the category 'animals'. With the increasing development of novel item-level metrics of semantic fluency, a concern around the validity of item-level analyses could be that personal background factors (e.g., hobbies like birdwatching or fishing) may disproportionally influence performance. We analyzed animal fluency performance at the item level and investigated the prevalence of individuals with abundant knowledge in specific classes of animals (e.g., birds, fish, insects) and the relationship of such knowledge with personal background factors and other cognitive tasks (episodic memory and executive functioning).

Method

Participants included 736 Dutch middle-aged to older adults from the SMART-MR cohort (mean age 58 ± 9.4 years, 18% women). Individuals were asked to name as many animals as possible for 2 min. Number of people with abundant animal class knowledge was calculated for the ability to recall a series of minimum ≥5 and up to ≥15 animals within a specific class with at most one interruption by an animal from another class. Subsequent analyses to investigate relationships of abundant class knowledge with sociodemographic characteristics (t-tests and chi-square tests) and cognitive performance (linear regressions) were performed for a cut-off of ≥10 animals within a specific class (90th percentile), with a sensitivity analysis for ≥7 animals (67th percentile).

Results

A total of 416 (56.2%) participants recalled a series of ≥5 animals from a specific class, 245 (33.3%) participants recalled ≥7, 78 (10.6%) participants recalled ≥10, and 8 (1.1%) participants recalled ≥15. Those who recalled a series of at least 10 animals within a class were older, more often men, and more often retired than those who did not. Moreover, they had a higher total score on animal fluency, letter fluency (i.e., executive functioning), and episodic memory tasks compared to those who did not.

Discussion

Our results suggest that the benefit of abundant animal class knowledge gained by personal background does not disproportionally influence animal fluency performance as individuals with such knowledge also performed better on other cognitive tasks unrelated to abundant knowledge of animal classes.

Posterior white matter hyperintensities are associated with reduced medial temporal lobe subregional integrity and long-term memory in older adults

White matter hyperintensities are a marker of small vessel cerebrovascular disease that are strongly related to cognition in older adults. Similarly, medial temporal lobe atrophy is well-documented in aging and Alzheimer's disease and is associated with memory decline. Here, we assessed the relationship between lobar white matter hyperintensities, medial temporal lobe subregional volumes, and hippocampal memory in older adults. We collected MRI scans in a sample of 139 older adults without dementia (88 females, mean age (SD) = 76.95 (10.61)). Participants were administered the Rey Auditory Verbal Learning Test (RAVLT). Regression analyses tested for associations among medial temporal lobe subregional volumes, regional white matter hyperintensities and memory, while adjusting for age, sex, and education and correcting for multiple comparisons. Increased occipital white matter hyperintensities were related to worse RAVLT delayed recall performance, and to reduced CA1, dentate gyrus, perirhinal cortex (Brodmann area 36), and parahippocampal cortex volumes. These medial temporal lobe subregional volumes were related to delayed recall performance. The association of occipital white matter hyperintensities with delayed recall performance was fully mediated statistically only by perirhinal cortex volume. These results suggest that white matter hyperintensities may be associated with memory decline through their impact on medial temporal lobe atrophy. These findings provide new insights into the role of vascular pathologies in memory loss in older adults and suggest that future studies should further examine the neural mechanisms of these relationships in longitudinal samples.

Association of childhood maltreatment and cortisol with the severity and stability of depression symptoms

BACKGROUND

Little is known about patterns of depression symptoms over time in older adults. This study aims to assess the association of childhood maltreatment and cortisol levels with latent classes of depression symptoms over ten years in older adults.

METHODS

A total of 752 participants (mean age 61.7±9.5, female 18%) in the Second Manifestations of ARTerial disease-Memory, depression and aging (SMART-Medea) study provided up to twenty measures of depression symptoms over ten years based on the Patient Health Questionnaire-9 (PHQ-9). At baseline, salivary cortisol was measured, and childhood maltreatment was assessed. Responses to the PHQ-9 were indicators in a latent class analysis. Multinomial regression determined associations between class membership and cortisol and maltreatment, adjusting for age, sex, and education.

RESULTS

Four distinct classes were identified; never depressed (n=275, 37%), energy/sleep difficulties (n=237, 32%), mild depression symptoms (n=152, 20%) and fluctuating severe depression (n=88, 12%). Childhood maltreatment was associated with mild depression symptoms (OR=1.95, 95% CI: 1.17-3.25) and fluctuating severe depression (OR=3.50, 95% CI: 1.99-6.15). Blunted morning cortisol was associated with energy/sleep difficulties (OR=0.98, 95% CI: 0.95-1.00) and fluctuating severe depression (OR=0.96, 95% CI: 0.92-0.99). There was no evidence for interaction between maltreatment and cortisol.

LIMITATIONS

There is limited generalizability due to the cohort consisting of participants with atherosclerosis and being mostly male. This study utilizes retrospective self-reporting of childhood maltreatment.

CONCLUSION

Childhood maltreatment and blunted morning cortisol independently contribute to a worse depression course. Blunted morning cortisol may contribute to sub-clinical depression symptoms, specifically difficulties with energy levels and sleep.

Relationship of the Triglyceride-Glucose Index with Subclinical White Matter Hypersensitivities of Presumed Vascular Origin Among Community-Dwelling Koreans

Purpose

The triglyceride-glucose (TyG) index, a widely accessible measure, has been a surrogate indicator of peripheral insulin resistance, and its clinical importance continues to grow in East Asia. We hypothesized that the TyG index is relevant to subclinical white matter hypersensitivities (WMHs) of presumed vascular origin among community-dwelling Koreans.

Methods

We investigated the relationship between the TyG index and WMHs on brain magnetic resonance imaging scans in 2417 Koreans over 45 years of age without a history of cancer, stroke, or ischemic heart disease. The study population was divided into four groups according to the TyG index quartiles. Using multiple logistic regression analysis, we assessed the odds ratios (ORs) and 95% confidence intervals (95% CIs) for WMHs across the TyG index quartiles.

Results

The prevalence of WMHs was significantly higher in the fourth TyG index quartile, with an overall rate of 9.3%. After adjusting for potential confounding variables, the ORs of WMHs for the TyG index quartiles were 1.00, 1.47 (95% CI, 0.91–2.40), 1.76 (95% CI, 1.05–2.97), and 6.79 (95% CI, 3.85–1.54), respectively.

Conclusion

We found that higher TyG index values were associated with the brain’s WMHs of presumed vascular origin. Our findings suggest that the serum TyG index could be an additional valuable biomarker for assessing the risk of cerebral small vessel disease in the preclinical stage.

Hypertension-induced cognitive impairment: from pathophysiology to public health

Hypertension affects two-thirds of people aged >60 years and significantly increases the risk of both vascular cognitive impairment and Alzheimer's disease. Hypertension compromises the structural and functional integrity of the cerebral microcirculation, promoting microvascular rarefaction, cerebromicrovascular endothelial dysfunction and neurovascular uncoupling, which impair cerebral blood supply. In addition, hypertension disrupts the blood-brain barrier, promoting neuroinflammation and exacerbation of amyloid pathologies. Ageing is characterized by multifaceted homeostatic dysfunction and impaired cellular stress resilience, which exacerbate the deleterious cerebromicrovascular effects of hypertension. Neuroradiological markers of hypertension-induced cerebral small vessel disease include white matter hyperintensities, lacunar infarcts and microhaemorrhages, all of which are associated with cognitive decline. Use of pharmaceutical and lifestyle interventions that reduce blood pressure, in combination with treatments that promote microvascular health, have the potential to prevent or delay the pathogenesis of vascular cognitive impairment and Alzheimer's disease in patients with hypertension.

Circulating Progenitor Cells and Cognitive Impairment in Men and Women with Coronary Artery Disease

BACKGROUND

Circulating progenitor cells (CPC) have been associated with memory function and cognitive impairment in healthy adults. However, it is unclear whether such associations also exist in patients with coronary artery disease (CAD).

OBJECTIVE

To assess the association between CPCs and memory performance among individuals with CAD.

METHODS

We assessed cognitive function in 509 patients with CAD using the verbal and visual Memory subtests of the Wechsler memory scale-IV and the Trail Making Test parts A and B. CPCs were enumerated with flow cytometry as CD45med/CD34+ blood mononuclear cells, those co-expressing other epitopes representing populations enriched for hematopoietic and endothelial progenitors.

RESULTS

After adjusting for demographic and cardiovascular risk factors, lower number of endothelial progenitor cell counts were independently associated with lower visual and verbal memory scores (p for all < 0.05). There was a significant interaction in the magnitude of this association with race (p < 0.01), such that the association of verbal memory scores with endothelial progenitor subsets was present in Black but not in non-Black participants. No associations were present with the hematopoietic progenitor-enriched cells or with the Trail Making Tests.

CONCLUSION

Lower numbers of circulating endothelial progenitor cells are associated with cognitive impairment in patients with CAD, suggesting a protective effect of repair/regeneration processes in the maintenance of cognitive status. Impairment of verbal memory function was more strongly associated with lower CPC counts in Black compared to non-Black participants with CAD. Whether strategies designed to improve regenerative capacity will improve cognition needs further study.

Incident cerebral lacunes: A review

Lacunes on magnetic resonance imaging (MRI) are considered as a key hallmark for evaluating the progression and severity of cerebral small vessel diseases. We aimed to review the MRI diagnostic criteria, frequency, predictors and clinical impact of incident lacunes in the largest longitudinal studies. Analyses were restricted to cohort studies of more than 50 individuals that investigated incident lacunes over a duration of at least one year. We observed that: (1) MRI parameters and definition of lacunes are inconsistent across studies, (2) the frequency of incident lacunes is strongly related to the previous clinical and MRI status at individual level, (3) both age and hypertension diagnosed at onset predict incident lacunes but the exact impact of blood pressure level during follow-up remains undetermined, (4) the clinical correlates of these lesions on cognition are repeatedly observed but the exact consequences on motor or gait performances are not always evaluated. Homogenization of imaging techniques, the use of strict diagnostic criteria and a broader clinical assessment considering motor and gait performances should be recommended in future longitudinal studies of incident lacunes including clinical trials testing preventative treatments in cerebral small vessel diseases.

Hippocampal sulcal cavities: prevalence, risk factors and association with cognitive performance. The SMART-Medea study and PREDICT-MR study

Hippocampal sulcal cavities (HSCs) are frequently observed on MRI, but their etiology and relevance is unclear. HSCs may be anatomical variations, or result from pathology. We assessed the presence of HSCs, and their cross-sectional association with demographics, vascular risk factors and cognitive functioning in two study samples. Within a random sample of 92 patients with vascular disease from the SMART-Medea study (mean age = 62, SD = 9 years) and 83 primary care patients from the PREDICT-MR study (mean age = 62, SD = 12 years) one rater manually scored HSCs at 1.5 T 3D T1-weighted coronal images blind to patient information. We estimated relative risks of age, sex and vascular risk factors with presence of HSCs using Poisson regression with log-link function and robust standard errors adjusted for age and sex. Using ANCOVA adjusted for age, sex, and education we estimated the association of the number of HSCs with memory, executive functioning, speed, and working memory. In the SMART-Medea study HSCs were present in 65% and in 52% in the PREDICT-MR study (χ2 = 2.99, df = 1, p = 0.08). In both samples, no significant associations were observed between presence of HSCs and age (SMART-Medea: RR = 1.00; 95%CI 0.98-1.01; PREDICT-MR: RR = 1.01; 95%CI 0.99-1.03), sex, or vascular risk factors. Also, no associations between HSCs and cognitive functioning were found in either sample. HSCs are frequently observed on 1.5 T MRI. Our findings suggest that, in patients with a history of vascular disease and primary care attendees, HSCs are part of normal anatomic variation of the human hippocampus rather than markers of pathology.

Small Vessel Cerebrovascular Pathology Identified by Magnetic Resonance Imaging Is Prevalent in Alzheimer's Disease and Mild Cognitive Impairment: A Potential Target for Intervention

BACKGROUND

There is evidence that Alzheimer's disease (AD) has significant cerebrovascular etiopathogenesis. Understanding potentially modifiable risk factors for vascular disease can help design long-term intervention strategies for controlling or preventing cognitive dysfunction attributable to cerebrovascular disease.

OBJECTIVE

To evaluate the presence and severity of markers of cerebrovascular pathology, its relationship to diagnostic categories of dementia, including AD, and association with the metabolic biomarker homocysteine.

METHODS

In a cross-sectional observational study, 340 community-dwelling elders received a clinical evaluation including brain MRI and neuropsychological tests. Dementia and mild cognitive impairment (MCI) were diagnosed by consensus committee. Fasting total plasma homocysteine was measured. Statistical analyses were adjusted for demographics and cerebrovascular risk factors.

RESULTS

Nearly 25% of those diagnosed with AD had small vessel infarcts (SVI). Periventricular white matter hyperintensity (pvWMHI) was prevalent in participants with AD (61%) or MCI (amnesic 61% and non-amnesic 54%, respectively). Participants with SVI and/or pvWMHI also had greater brain atrophy. Homocysteine concentrations were higher in individuals with cerebrovascular findings than in those without. In individuals with cerebrovascular disease, homocysteine was inversely related to executive function (p = 0.022) and directly related to degree of brain atrophy (p = 0.009).

CONCLUSIONS

We demonstrated a significant prevalence of small vessel markers of cerebrovascular pathology in individuals diagnosed with AD, with a significant concurrence between cerebrovascular disease and brain and ventricular atrophy. While current research on AD has focused on amyloid-βpeptide deposition, tau-pathology, and microglial activation and inflammation, greater attention to the cerebrovascular contribution to this neurodegenerative disease presents an additional target for therapeutic prevention and intervention.

Subjective cognitive decline, brain imaging biomarkers, and cognitive functioning in patients with a history of vascular disease: the SMART-Medea study

We estimated associations of subjective cognitive decline (SCD) with neuroimaging markers of dementia and cognitive functioning in patients with a history of vascular disease without objective cognitive impairment. Within the Second Manifestations of ARTerial disease-Memory, depression and aging study, 599 patients (62 ± 9 years) had 1.5 T brain magnetic resonance imaging and cognitive testing at the baseline and after 8 years of follow-up. Using multiple regression analyses, we estimated cross-sectional and longitudinal associations of SCD according to research criteria with volumes of total brain, hippocampus, white matter hyperintensities, and presence of lacunes and with memory, executive functioning, information processing speed, and working memory. SCD was associated with increased risk of lacunes at the baseline (relative risk = 1.48, 95% confidence interval: 1.03; 2.12) but not during follow-up. No significant associations with volumes of white matter hyperintensities, total brain, or hippocampus were observed. SCD was cross-sectionally associated with poorer executive functioning and speed but not during follow-up. More prospective studies are needed to further elucidate the relationship between SCD, brain imaging markers, and cognitive decline and the role of SCD in the preclinical stage of Alzheimer's disease.

Assessment of Explicitly Stated Interval Change on Noncontrast Head CT Radiology Reports

BACKGROUND AND PURPOSE

Consistent and standardized reporting of interval change for certain diagnoses may improve the clinical utility of radiology reports. The purpose of this study was to assess explicitly stated interval change of various findings in noncontrast head CT reports.

MATERIALS AND METHODS

A retrospective review was performed on successive noncontrast head CT radiology reports from the first 2 weeks of January 2014. Reports with at least 1 prior comparison CT scan were included. Reports with normal examination findings and those that made comparison with only other types of examinations (eg, MR imaging) were excluded. Descriptive and subgroup statistical analyses were performed.

RESULTS

In total, 200 patients with 230 reports and 979 radiographic findings were identified. The average interval between reports was 344.9 ± 695.9 days (range, 0-3556 days). Interval change was mentioned 67.3% (n = 659) of the time for all findings (n = 979). Explicitly stated interval change was significantly associated with nonremote findings (P < .001) and generalized statements of interval change (P < .001). The proportion of interval change reported ranged from 95.3% of the time for hemorrhagic to 36.4% for soft-tissue/osseous categorizations.

CONCLUSIONS

Interval change reporting was variable, mentioned for 67.3% of noncontrast head CT report findings with a prior comparison CT scan. Structured radiology reports may improve the consistent and clear reporting of interval change for certain findings.

Characterization of White Matter Hyperintensities in Large-Scale MRI-Studies

Background: White matter hyperintensities of presumed vascular origin (WMH) are a common finding in elderly people and a growing social malady in the aging western societies. As a manifestation of cerebral small vessel disease, WMH are considered to be a vascular contributor to various sequelae such as cognitive decline, dementia, depression, stroke as well as gait and balance problems. While pathophysiology and therapeutical options remain unclear, large-scale studies have improved the understanding of WMH, particularly by quantitative assessment of WMH. In this review, we aimed to provide an overview of the characteristics, research subjects and segmentation techniques of these studies.

Methods: We performed a systematic review according to the PRISMA statement. One thousand one hundred and ninety-six potentially relevant articles were identified via PubMed search. Six further articles classified as relevant were added manually. After applying a catalog of exclusion criteria, remaining articles were read full-text and the following information was extracted into a standardized form: year of publication, sample size, mean age of subjects in the study, the cohort included, and segmentation details like the definition of WMH, the segmentation method, reference to methods papers as well as validation measurements.

Results: Our search resulted in the inclusion and full-text review of 137 articles. One hundred and thirty-four of them belonged to 37 prospective cohort studies. Median sample size was 1,030 with no increase over the covered years. Eighty studies investigated in the association of WMH and risk factors. Most of them focussed on arterial hypertension, diabetes mellitus type II and Apo E genotype and inflammatory markers. Sixty-three studies analyzed the association of WMH and secondary conditions like cognitive decline, mood disorder and brain atrophy. Studies applied various methods based on manual (3), semi-automated (57), and automated segmentation techniques (75). Only 18% of the articles referred to an explicit definition of WMH.

Discussion: The review yielded a large number of studies engaged in WMH research. A remarkable variety of segmentation techniques was applied, and only a minority referred to a clear definition of WMH. Most addressed topics were risk factors and secondary clinical conditions. In conclusion, WMH research is a vivid field with a need for further standardization regarding definitions and used methods.

Cognitive functions and white matter lesions on magnetic resonance images in a sample of normal Iranian population with cardiovascular risk factors

PURPOSE

Due to a suggestive three-way relationship between brain structural disorders, microvascular lesions, and cognitive impairments, we aimed to examine the association of the volume and number of white matter hyperintensity lesions and lacunar infarcts with cognitive impairment among patients with cardiovascular risk factors in a sample of the Iranian population.

MATERIALS AND METHODS

This study was conducted on a total number of 156 normal subjects aged 30-74 years with cardiovascular risk factors. We used the Framingham general cardiovascular risk factors prediction model to calculate the likelihood of each risk factor. The total number of lacunar infarcts and the volume of white matter hyperintensity lesion were calculated in brain magnetic resonance imaging. Cognition status was assessed using the Montreal Cognitive Assessment questionnaire.

RESULTS

An adverse association was revealed between Montreal Cognitive Assessment score and different cardiovascular risk profiles including the Framingham body mass index score ( p < 0.001) and the Framingham lipid score ( p < 0.001). The total volume of white matter hyperintensity was negatively associated with total Montreal Cognitive Assessment cognition score ( p < 0.001). Our study also showed an adverse association between total number of lacunar infarcts and total Montreal Cognitive Assessment cognition score ( p = 0.038) and with some cognition components including memory ( p = 0.013), attention ( p = 0.037), abstraction ( p = 0.046), and orientation ( p = 0.002).

CONCLUSION

Periventricular lesions are associated with impaired memory, language, and visuoconstruction while subcortical lesions are associated with impairment in naming, attention, language, and abstraction functions in normal subjects with cardiovascular risk factors but without cardiovascular or cerebrovascular disorders.

Deep cerebral microbleeds are associated with the severity of lacunar infarcts and hypertension: A retrospective analysis

Cerebral microbleeds (CMBs) and lacunar infarcts are common manifestations of cerebral small vessel disease. However, the association between the location of CMBs and lacunar infarcts is unclear. Our study aimed to clarify the relationship between the location of CMBs and lacunar infarcts.This study retrospectively analyzed 166 patients with ischemic stroke or transient ischemic attacks admitted in the Geriatric Neurology Department of Chinese PLA General Hospital between February 2010 and December 2012. We collected clinical characteristics and risk factors of CMBs. The location of CMBs on T2*-weighted angiography was assessed by the Microbleed Anatomical Rating Scale. The number of lacunar infarcts and the severity of white matter hyperintensities were also recorded. The association between the location of CMBs and lacunar infarcts parameters was examined.CMBs were present in 77 (46.4%) patients. The presence [odds ratios (OR), 2.14; 95% confidence interval (CI), 1.02-4.48], number (OR, 1.17; 95% CI, 1.02-1.36 per lesion), severity (OR, 1.61; 95% CI, 1.07-2.42) of lacunar infarcts, and hypertension (OR, 5.76; 95% CI, 2.01-16.55) were independent risk factors for CMBs. Stratified by the location of CMBs, lobar CMBs and infratentorial CMBs did not show significant association with lacunar infarcts. Deep CMBs were significantly associated with the number (OR 1.18, 95% CI 1.03-1.36) and severity (OR 1.71, 95% CI 1.11-2.63) of lacunar infarcts. Moreover, the percentage of deep CMBs increased with the increased severity of lacunar infarcts (P = .003).Deep CMBs rather than lobar and infratentorial CMBs are associated with lacunar infarcts.

Associations between lesions and domain-specific cognitive decline in poststroke dementia

Objective

To investigate whether the effect of prestroke and stroke-related lesions on incident poststroke dementia (PSD) is mediated by a unique pattern of domain-specific cognitive impairment, and the relative strength of these anatomical–cognitive associations in predicting incident PSD.

Methods

In this incident case-control study (n = 150), we defined incident cases as acute stroke patients who developed PSD and controls as acute stroke patients who remained free from dementia at a 6 month follow-up, matched on age, prestroke cognitive status, and number of stroke-related lesions. MRI was performed at initial clinical presentation; neuropsychological assessments and clinical diagnosis of PSD was performed 6 months poststroke. Moderated mediation analysis evaluated the interactions among PSD, anatomical lesions, cognitive domains, and individual demographic and medical characteristics.

Results

Compared to stroke-related lesions, prestroke lesions were associated with the widest range of cognitive domain impairments and had stronger clinical utility in predicting incident PSD. Specifically, global cortical atrophy (GCA) and deep white matter hyperintensities (WMH) were indirectly associated with PSD by disrupting executive functions, memory, and language. Acute infarcts were indirectly associated with PSD by disrupting executive functions and language. The strongest mediator was executive dysfunction, increasing risk of PSD in patients with deep WMH, GCA, and large infarcts by more than 9 times, with sex and educational attainment moderating the magnitude of association. Periventricular WMH were directly associated with incident PSD but not mediated by deficits in cognitive domains.

Conclusion

We provide an anatomical–cognitive framework that can be applied to stratify patients at highest risk of PSD and to guide personalized interventions.

Cerebral changes and cognitive impairment after an ischemic heart disease: a multimodal MRI study

Three to 6 months after an acute coronary syndrome (ACS), cognitive impairment is observed in more than 30 % of the patients, mainly in executive functioning. The aim of this study was to investigate, using multimodal MRI, cerebral anatomo-functional substratum of executive dysfunction. Thirty-three patients were recruited 4 ± 1 months after a first ACS. Executive functions were evaluated with the Trail-Making-Test-B (TMTB) at baseline (ie 4 ± 1 months after ACS) and 6 months later (ie 10 ± 1 months after ACS). Using both time-points, we identified 3 groups of patients according to normative data based on age, gender and education level: 15 'cognitively normal' patients without impairment at each follow-up, 10 'transient impaired' patients with an impairment only at baseline and 8 'impairing' patients with an impairment only at follow-up. We explored, in the whole-brain, the structural integrity using Voxel-Based Morphometry and Tract-Based Spatial Statistics and the resting-state functional connectivity using Network-Based Statistics. No structural difference was observed between impaired and cognitively normal patients. At the functional level, compared to the 'cognitively normal' group, the 'transient impaired' patients presented an increased functional connectivity in a network centered on middle-orbito-frontal regions, whereas the 'impairing' patients presented only a non-significant decrease of functional connectivity. Executive dysfunction in ACS patients is associated to functional but no structural characteristics, particularly to an increased functional connectivity in cognitive networks in transient impaired patients. Further studies with larger sample size are needed to confirm these results and to determine if these patients could be at higher risk for developing permanent cognitive disorders.

Cerebral white matter lesion burden is associated with the degree of aortic valve calcification and predicts peri-procedural cerebrovascular events in patients undergoing transcatheter aortic valve implantation (TAVI)

OBJECTIVES

To investigate the impact of aortic valve calcification and brain morphology on acute peri-procedural cerebrovascular events (CVEs) in patients undergoing transcatheter aortic valve implantation (TAVI).

BACKGROUND

Aortic valve calcification and stenosis can be assessed with echocardiography. Cerebral magnetic resonance imaging (MRI) depicts and quantifies morphological signs of hypoperfusion and vascular embolism, which is of special interest in patients with severe aortic stenosis. Furthermore, subjects who undergo TAVI are prone to suffer of clinically silent peri-procedural CVEs.

METHODS

A total of 119 patients referred to TAVI were investigated for aortic valve calcification using trans-esophageal echocardiography. Cerebral MRI prior to and immediate after implantation was performed in all patients using a dedicated scan protocol. Prior to TAVI, brain morphology was characterized. Post TAVI, brains were investigated for the onset of acute peri-procedural CVEs using diffusion weighted imaging (DWI).

RESULTS

Seventy-eight patients (65.5%) revealed acute peri-procedural CVEs on MRI after TAVI with a favor of the left hemisphere (57.5%). The degree of valve calcification was associated with peri-procedural CVEs. Patients with a high WML burden had an increased risk for CVEs ((OR) 2.36 (95% CI: 1.09-5.15; P = 0.037)), especially when distributed periventricular ((OR: 3.27; 95% CI: 1.47-7.26; P = 0.0038)).

CONCLUSION

In patients undergoing TAVI, the degree of aortic valve calcification and periventricular WML burden were correlated with acute peri-procedural CVEs. Future studies are needed to evaluate their independent value for the long-term clinical outcome.

Hippocampal volume and the course of depressive symptoms over eight years of follow-up

OBJECTIVE

To estimate the association between hippocampal and total brain volume and the course of depressive symptoms over eight years of follow-up in patients with a history of vascular disease.

METHOD

Within the SMART-Medea study, 636 participants (62 ± 10 years) had a 1.5-tesla brain MRI obtaining hippocampal and total brain volumes. Depressive symptoms were assessed with the Patient Health Questionnaire-9 biannually during eight-year follow-up. Generalized estimating equation models with robust standard errors were used to assess the associations of hippocampal and total brain volumes with depressive symptoms during follow-up adjusting for age, sex, education, and intracranial volume. An interaction term between volume and time (6-month intervals) was included to examine whether the course of depressive symptoms differed according to hippocampal and total brain volume.

RESULTS

The mean PHQ-9 score was 2.8 ± 3.5. Smaller hippocampal volumes were associated with an increasing course of depressive symptom levels, while larger volumes were associated with decreasing levels (P-value interaction = 0.07). Smaller total brain volume was associated with consistently higher levels of depressive symptoms, but not with change in course of depressive symptoms (P-value interaction = 0.45).

CONCLUSION

Smaller hippocampal volume but not total brain volume is associated with poorer course of depressive symptoms over eight years of follow-up.

The natural course of elevated levels of depressive symptoms in patients with vascular disease over eight years of follow-up. The SMART-Medea study

BACKGROUND

Patients with cardiovascular disease have an increased risk for depression, and depression predicts poor prognosis in these patients, but the long-term course of depression is not known. We studied the natural course of elevated levels of depressive symptoms in patients with cardiovascular disease over eight years follow-up.

METHODS

Within the Second Manifestations of ARTerial disease - Memory, depression and aging (SMART-Medea) study, depressive symptoms were assessed with the Patient Health Questionnaire-9 (PHQ-9) in 690 patients (62±10 years) at baseline and bi-annually during 8 years follow-up. Natural course was described for symptom severity and course type (never, single episode, intermittent, and chronic) based on the cut-off point of ≥6 on the PHQ-9. Using multinomial regression analysis (reference: never depressed) we estimated age- and sex-adjusted odds ratios (OR) for the associations of demographic factors and vascular disease categories with course type.

RESULTS

Of the 690 patients, 60% was never depressed, 10% had a single episode, 19% had an intermittent and 11% a chronic course of depression. Increased risk for chronic course was observed for women (OR=3.42; 95% CI=1.98-5.90), those with younger age (OR=3.20; 95% CI=1.73-5.94), and for patients with cerebrovascular disease when compared to patients with coronary artery disease (OR=2.50; 95% CI=1.31-4.78).

LIMITATIONS

No information was available on clinical diagnosed major depressive disorder and/or clinical events during follow-up.

CONCLUSIONS

In patients with cardiovascular disease, an intermittent or chronic course of elevated levels of depressive symptoms is very common. Patients with cardiovascular disease may require more careful clinical monitoring and management of depressive symptoms.

Childhood maltreatment modifies the relationship of depression with hippocampal volume

BACKGROUND

Childhood maltreatment (CM) may modify the relationship between major depressive disorder (MDD) and hippocampal volume reduction. To disentangle the impact of MDD and CM on hippocampal volume we investigated the association between MDD and hippocampal volume in persons with and without a history of CM in two independent cohorts.

METHOD

We used data of 262 participants from the Netherlands Study of Depression and Anxiety (NESDA) (mean age 37 years, 32% male) and 636 participants from the SMART-Medea study (mean age 61 years, 81% male). In both studies a 12-month diagnosis of MDD and CM were assessed using a diagnostic interview. Hippocampal volume was measured in NESDA using FreeSurfer software on 3-T magnetic resonance (MR) images and in SMART it was manually outlined on 1.5-T MR images. With analysis of covariance adjusted for intracranial volume, age, gender and lifestyle factors we estimated the effects of MDD and CM on hippocampal volume.

RESULTS

In both cohorts CM was not significantly associated with hippocampal volume. After pooling the data MDD was associated with smaller hippocampal volume (B = -138.90 mm(3), p = 0.05) and the interaction between MDD and CM reached significance (p = 0.04); in participants with CM, MDD was related to smaller hippocampal volume (NESDA: B = -316.8 mm(3), p = 0.02; SMART: B = -407.6, p = 0.046), but not in participants without CM (p > 0.05).

CONCLUSIONS

Our study shows that in two independent cohorts, particularly in individuals with CM, a diagnosis of MDD is related to smaller hippocampal volume. Prospective studies are needed to further determine through which mechanism CM may amplify the relationship between MDD and hippocampal volume.

Cerebellar Cortical Infarct Cavities

Background and Purpose—

Small cerebellar infarct cavities have been recently found on magnetic resonance imaging (MRI) to preferentially involve the cerebellar cortex, but epidemiological studies are lacking. We aimed to determine the prevalence and risk factor profiles of cerebellar cortical infarct cavities (≤1.5 cm) as well as their association with MRI markers of cerebrovascular disease and functioning.

Methods—

We analyzed the 1.5 Tesla MRI of 636 patients (mean age, 62±9 years; 81% men) from the Second Manifestations of Arterial Disease-Memory, Depression and Aging (SMART-Medea) study. Logistic regression analyses were performed to estimate the associations of age, sex, vascular risk factors, MRI markers of cerebrovascular disease, and functioning with cerebellar cortical cavities, adjusted for age and sex.

Results—

Cerebellar cortical infarct cavities occurred on MRI in 10% of patients and were significantly associated with age, intima-media thickness (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.1–3.7), high levels of homocysteinemia (OR, 1.8; 95% CI, 1.0–3.3), cortical infarcts (OR, 2.9; 95% CI, 1.6–5.4), gray matter lacunes of presumed vascular origin (OR, 3.0; 95% CI, 1.6–5.8), brain stem infarcts (OR, 5.1; 95% CI, 1.9–13.6), and decreased brain parenchymal fraction (OR, 0.84; 95% CI, 0.74–0.94), but not with white matter hyperintensities (OR, 1.2; 95% CI, 0.8–1.8) or white matter lacunes of presumed vascular origin (OR, 1.1; 95% CI, 0.5–2.5). They were also associated with worse physical functioning (OR 0.96; 95% CI, 0.94 to 0.99) but not with mental functioning.

Conclusions—

Cerebellar cortical infarct cavities are far more common than previously assumed based on symptomatic case series and are associated with markers of atherothromboembolic cerebrovascular disease.

Hypertensive Target Organ Damage and Longitudinal Changes in Brain Structure and Function: The Second Manifestations of Arterial Disease-Magnetic Resonance Study

Hypertension has been related to structural and functional brain changes. In high-risk populations, hypertensive target organ damage might better represent exposure to high blood pressure than the blood pressure measurement itself. We examined the association of hypertensive target organ damage with longitudinal changes in brain structure and function within the Second Manifestations of Arterial Disease-Magnetic Resonance (SMART-MR) study. Renal function, albuminuria, and left ventricular hypertrophy on electrocardiography were measured in 663 patients with manifest arterial disease (mean age, 57±9 years; 81% men). Automated brain segmentation was used to quantify progression of global brain atrophy (change in brain parenchymal fraction) and progression of cerebral small vessel disease on 1.5T magnetic resonance imaging, and memory and executive functioning were assessed at baseline and after on average 3.9 years of follow-up. Regression analyses showed that an increasing number of signs of target organ damage was associated with more progression of global brain atrophy and more rapid decline in memory performance. Compared with no target organ damage, mean differences in change in brain parenchymal fraction (95% confidence interval) for 1 and ≥2 signs of organ damage were -0.12 (-0.30; 0.06) and -0.41 (-0.77; -0.05) % intracranial volume, and mean (95% confidence interval) differences in change in memory performance (z score) were -0.15 (-0.29; -0.00) and -0.27 (-0.54; -0.01). Results were independent of blood pressure, antihypertensive treatment, and other confounders. Hypertension target organ damage was not associated with progression of cerebral small vessel disease or change in executive functioning. Routinely assessed signs of hypertensive target organ damage, and in particular impaired renal function, could be used to identify patients at the highest risk of cognitive decline.

Cerebellar infarct patterns: The SMART-Medea study

OBJECTIVE

Previous studies on cerebellar infarcts have been largely restricted to acute infarcts in patients with clinical symptoms, and cerebellar infarcts have been evaluated with the almost exclusive use of transversal MR images. We aimed to document the occurrence and 3D-imaging patterns of cerebellar infarcts presenting as an incidental finding on MRI.

METHODS

We analysed the 1.5 Tesla MRI, including 3D T1-weighted datasets, of 636 patients (mean age 62 ± 9 years, 81% male) from the SMART-Medea study. Cerebellar infarct analyses included an assessment of size, cavitation and gliosis, of grey and white matter involvement, and of infarct topography.

RESULTS

One or more cerebellar infarcts (mean 1.97; range 1-11) were detected in 70 out of 636 patients (11%), with a total amount of 138 infarcts identified, 135 of which showed evidence of cavitation. The average mean axial diameter was 7 mm (range 2-54 mm), and 131 infarcts (95%) were smaller than 20 mm. Hundred-thirty-four infarcts (97%) involved the cortex, of which 12 in combination with subcortical white matter. No infarcts were restricted to subcortical branches of white matter. Small cortical infarcts involved the apex of a deep (pattern 1) or shallow fissure (pattern 2), or occurred alongside one (pattern 3) or opposite sides (pattern 4) of a fissure. Most (87%) cerebellar infarcts were situated in the posterior lobe.

CONCLUSIONS

Small cerebellar infarcts proved to be much more common than larger infarcts, and preferentially involved the cortex. Small cortical infarcts predominantly involved the posterior lobes, showed sparing of subcortical white matter and occurred in characteristic topographic patterns.

Shape abnormalities of the caudate nucleus correlate with poorer gait and balance: results from a subset of the LADIS study

OBJECTIVE

Functional deficits seen in several neurodegenerative disorders have been linked with dysfunction in frontostriatal circuits and with associated shape alterations in striatal structures. The severity of visible white matter hyperintensities (WMHs) on magnetic resonance imaging has been found to correlate with poorer performance on measures of gait and balance. This study aimed to determine whether striatal volume and shape changes were correlated with gait dysfunction.

METHODS

Magnetic resonance imaging scans and clinical gait/balance data (scores from the Short Physical Performance Battery [SPPB]) were sourced from 66 subjects in the previously published LADIS trial, performed in nondisabled individuals older than age 65 years with WMHs at study entry. Data were obtained at study entry and at 3-year follow-up. Caudate nuclei and putamina were manually traced using a previously published method and volumes calculated. The relationships between volume and physical performance on the SPPB were investigated with shape analysis using the spherical harmonic shape description toolkit.

RESULTS

There was no correlation between the severity of WMHs and striatal volumes. Caudate nuclei volume correlated with performance on the SPPB at baseline but not at follow-up, with subsequent shape analysis showing left caudate changes occurred in areas corresponding to inputs of the dorsolateral prefrontal, premotor, and motor cortex. There was no correlation between putamen volumes and performance on the SPPB.

CONCLUSION

Disruption in frontostriatal circuits may play a role in mediating poorer physical performance in individuals with WMHs. Striatal volume and shape changes may be suitable biomarkers for functional changes in this population.

Cerebral microbleeds are associated with worse cognitive function in the nondemented elderly with small vessel disease

Background

Cerebral small vessel disease (SVD) is a leading cause of cognitive decline in the elderly. Cerebral microbleeds (CMBs) have emerged as an important manifestation of cerebral SVD, in addition to lacunar infarcts and white matter lesions (WMLs). We investigated whether the presence and location of CMBs in elderly subjects were associated with cognitive function, independent of lacunar infarcts and WMLs.

Methods

One hundred and forty-eight nondemented elderly with SVD, defined as the presence of lacunar infarcts and/or WMLs on magnetic resonance imaging (MRI), were studied. Executive function and global cognition were assessed by the Frontal Assessment Battery (FAB) and Mini-Mental State Examination (MMSE), respectively. The differences in the scores for the FAB and MMSE between CMB-positive and CMB-negative subjects were calculated after adjusting for possible confounders.

Results

The mean age of the subjects was 72.4 ± 8.6 years. CMBs were detected in 48 subjects (32%), with a mean number of CMBs per subject of 1.6 (range 0-31). Among CMB-positive subjects, 42 (87.5%) had CMBs in deep or infratentorial regions with or without lobar CMBs, and 6 (12.5%) had CMBs in strictly lobar regions. The presence of CMBs was significantly associated with FAB and MMSE scores after adjustment for age, years of education, brain volume and the presence of lacunar infarcts (for the FAB) or severe WMLs (for the MMSE). The presence of CMBs in the basal ganglia, in the thalamus or in the lobar regions was associated with FAB scores, while that in the lobar regions was associated with MMSE scores. However, there was no association between CMBs in the infratentorial regions and cognitive parameters.

Conclusions

In nondemented elderly with SVD on MRI, the presence of CMBs was independently associated with worse executive and global cognitive functions. CMBs seemed to reflect hypertensive microangiopathy in this population, and CMBs in specific areas may play an important role in cognitive function.

Alteraciones neuropsicológicas asociadas en pacientes con infarto lacunar

Existe poca evidencia del deterioro cognoscitivo que defina el perfil del paciente con Infarto Lacunar (IL). El propósito de este estudio fue identificar las alteraciones neuropsicológicas en este tipo de pacientes. La muestra estuvo compuesta por 16 pacientes con IL y 16 participantes sanos con una edad promedio de 63 ± 9.41 y 64.75 ± 9.06 años y una escolaridad de 7.55 ± 4.34 y 7.94 ± 3.51, respectivamente. Se valoró la función cognoscitiva mediante un instrumento de tamizaje y una batería neuropsicológica. El análisis estadístico se llevó a cabo a través de la prueba Kruskal-Wallis y la U de Man-Whitney. Los pacientes con IL se caracterizan por la alteración de dominios como planeación, fluidez verbal, cambio atencional, habilidad visoconstructiva y velocidad de procesamiento de la información (p < 0.050). El IL se relaciona con el deterioro del funcionamiento ejecutivo y de velocidad de procesamiento, debido a la interrupción de circuitos frontocortico-subcorticales asociados con su correcto desempeño.

Cognitive impairments associated with medial temporal atrophy and white matter hyperintensities: an MRI study in memory clinic patients

In this retrospective study, we investigated the independent effects of white matter hyperintensities (WMH) and hippocampal atrophy on cognitive functions in a broad sample of patients seen in a memory clinic. To ensure generalizability, these associations were examined irrespective of diagnosis and with minimal exclusion criteria. Next to these independent effects, interactions between WMH and hippocampal atrophy were examined. Between January 2006 and September 2011 a total of 500 patients visited the memory clinic, 397 of whom were included. Magnetic resonance images of 397 patients were visually analyzed for WMH, medial temporal atrophy (MTA), and global atrophy. We evaluated the association of WMH and MTA with the following cognitive domains: global cognition, episodic memory, working memory, executive function and psychomotor speed. Main effects and interaction effects were examined by means of correlation and regression analyses. In the regression analyses, we controlled for potential confounding effects of global atrophy. The correlational results revealed that WMH were associated with global cognition, executive function and psychomotor speed, whereas a trend was found for episodic memory. MTA was associated with all these four cognitive domains; an additional trend was observed for working memory. Hierarchical regression analyses revealed main independent effects of MTA for episodic memory, executive function, psychomotor speed and global cognition; WMH were only associated with global cognition. The interaction between MTA and WMH was significant for episodic memory only. This study demonstrates that predominantly MTA is an independent predictor not only for memory function, with which is it classically associated, but also for global cognition and executive function. Taken together, MTA may be an important correlate of cognitive deficits found in people attending the memory clinic.

Executive dysfunction correlates with caudate nucleus atrophy in patients with white matter changes on MRI: a subset of LADIS

White matter changes (WMC) are common magnetic resonance imaging (MRI) findings, particularly in the elderly. Recent studies such as the Leukoaraiosis and Disability Study (LADIS) have found that WMC relate to adverse outcomes including cognitive impairment, depression, disability, unsteadiness and falls in cross-sectional and follow-up studies. Frontostriatal (or frontosubcortical) brain circuits may serve many of these functions, with the caudate nuclei playing a role in convergence of cognitive functions. This study aimed to determine whether reduced caudate volume relates to cognitive functions (executive functions, memory functions and speed of processing) and WMC. We determined caudate nuclei volumes, through manual tracing, on a subgroup of the LADIS study (n=66) from four centres with baseline and 3-year follow-up MRI scans. Regression analysis was used to assess relationships between caudate volume, cognitive function and WMC. Severity of WMC did not relate to caudate volume. Smaller caudate volumes were significantly associated with poorer executive functioning at baseline and at 3 years, but were not associated with scores of memory or speed of processing. Thus, in patients with WMC, a surrogate of small vessel disease, caudate atrophy relates to the dysexecutive syndrome, supporting the role of caudate as an important part of the frontostriatal circuit.

Microbleeds and silent brain infarctions are differently associated with cognitive dysfunction in patients with advanced periventricular leukoaraiosis

BACKGROUND

Leukoaraiosis, microbleeds, and silent brain infarctions are phenotypes of small vessel disease. Leukoaraiosis is the most prevalent, and advanced periventricular leukoaraiosis is regarded as a strong predictor of cognitive dysfunction. Microbleeds and silent brain infarctions sometimes coexist with leukoaraiosis. This study aims to analyze the effects of microbleeds and silent brain infarctions on cognitive function of patients with advanced periventricular leukoaraiosis.

METHODS

227 patients with advanced periventricular leukoaraiosis were divided into control, MB, SBI, and MB&SBI groups. The presence and locations of microbleeds and silent brain infarctions were evaluated. Mini-Mental State Examination, Montreal Cognitive Assessment, Clock Drawing Test and Verbal Fluency Test were performed. Chi-square test and ANOVA to compare the characteristics of four groups, multiple linear regressions to identify the risk factors for cognitive dysfunction.

RESULTS

The scores in all four tests were lower in the MB and MB&SBI groups while only the scores in Clock Drawing Test and Verbal Fluency Test were lower in the SBI group than in the control group. Age and the presence of microbleeds were independent risk factors for the lower scores in all four tests, whereas the presence of silent brain infarctions was the only independent risk factor for the lower scores in Clock Drawing Test and Verbal Fluency Test. Lobar microbleeds had the most significant effect on cognitive function.

CONCLUSION

Microbleeds and silent brain infarctions were associated differently with cognitive impairment of patients with advanced periventricular leukoaraiosis. The effect of lobar microbleeds was the most significant.

Vascular brain lesions, brain atrophy, and cognitive decline. The Second Manifestations of ARTerial disease--Magnetic Resonance (SMART-MR) study

We examined the association between brain atrophy and vascular brain lesions (i.e., white matter lesions [WMLs] or brain infarcts), alone or in combination, with decline in memory and executive functioning over 4 years of follow-up in 448 patients (57 ± 9.5 years) with symptomatic atherosclerotic disease from the Second Manifestations of ARTerial disease--Magnetic Resonance SMART-MR study. Automated brain segmentation was used to quantify volumes of total brain, ventricles, cortical gray matter, and WMLs on 1.5-T magnetic resonance imaging (MRI). Brain infarcts were rated visually. WML volume was associated with significant decline in z score of executive functioning. No independent associations between MRI measures and memory decline were found. Significant declines in z scores of memory performance and of executive functioning were observed in patients with a combination of severe atrophy (upper quartile) and most vascular brain lesions (upper quartile) compared with those with minimal atrophy (lowest quartile) and fewest vascular brain lesions (lowest quartile). Our findings suggest that in patients with symptomatic atherosclerotic disease, the combination of brain atrophy and WMLs or brain infarcts accelerates cognitive decline over 4 years.

Are empirically-derived subtypes of mild cognitive impairment consistent with conventional subtypes?

Given the importance of identifying dementia prodromes for future treatment efforts, we examined two methods of diagnosing mild cognitive impairment (MCI) and determined whether empirically-derived MCI subtypes of these diagnostic methods were consistent with one another as well as with conventional MCI subtypes (i.e., amnestic, non-amnestic, single-domain, multi-domain). Participants were diagnosed with MCI using either conventional Petersen/Winblad criteria (n = 134; >1.5 SDs below normal on one test within a cognitive domain) or comprehensive neuropsychological criteria developed by Jak et al. (2009) (n = 80; >1 SD below normal on two tests within a domain), and the resulting samples were examined via hierarchical cluster and discriminant function analyses. Results showed that neuropsychological profiles varied depending on the criteria used to define MCI. Both criteria revealed an Amnestic subtype, consistent with prodromal Alzheimer's disease (AD), and a Mixed subtype that may capture individuals in advanced stages of MCI. The comprehensive criteria uniquely yielded Dysexecutive and Visuospatial subtypes, whereas the conventional criteria produced a subtype that performed within normal limits, suggesting its susceptibility to false positive diagnostic errors. Whether these empirically-derived MCI subtypes correspond to dissociable neuropathologic substrates and represent reliable prodromes of dementia will require additional follow-up.

Loss of entorhinal cortex and hippocampal volumes compared to whole brain volume in normal aging: the SMART-Medea study

In non-demented elderly age-related decline in hippocampal volume has often been observed, but it is not clear if this loss is disproportionate relative to other brain tissue. Few studies examined age-related volume loss of the entorhinal cortex. We investigated the association of age with hippocampal and entorhinal cortex (ERC) volumes in a large sample of middle-aged and older persons without dementia. Within the SMART-Medea study, cross-sectional analyses were performed in 453 non-demented subjects (mean age 62±9 years, 81% male) with a history of arterial disease. Hippocampal and ERC volumes were assessed by manual segmentation on three-dimensional fast field-echo sequence T1-weighted magnetic resonance images. Automated segmentation was used to quantify volumes of BV and ICV. Hippocampal and ERC volumes were divided by intracranial volume (ICV) as well as total brain volume (BV) to determine whether age-related differences were disproportionate relative to other brain tissue. Total crude hippocampal volume was 5.96±0.7 ml and total crude ERC volume was 0.34±0.06 ml. Linear regression analyses adjusted for sex showed that with increasing age, hippocampal volume divided by ICV decreased (B per year older=-0.01 ml; 95% CI -0.02 to -0.004). However, no age-related decline in hippocampal volume relative to BV was observed (B per year older=0.005 ml; 95% CI -0.002 to 0.01). No age-related decline in ERC volume relative to ICV or BV was observed. In this population of nondemented patients with a history of vascular disease no age-related decline in entorhinal cortex volume was observed and although hippocampal volume decreased with age, it was not disproportionate relative to total brain volume.

Mood problems increase the risk of mortality in patients with lacunar infarcts: the SMART-MR study

OBJECTIVE

A relationship between depression and mortality has been well established, but underlying mechanisms remain unclear. We investigated the influence of cerebral small vessel disease (CSVD), characterized by white matter lesions (WMLs) and lacunar infarcts, on the relationship between mood mortality during 6 years follow-up.

METHODS

Mood problems were assessed with the mental component summary of the 36-item Short-Form Medical Outcomes Study in 1110 patients with symptomatic atherosclerotic disease (mean age 59 years). Volumetric WML estimates were obtained with 1.5-T magnetic resonance imaging; lacunar infarcts were scored visually. Cox regression models were adjusted for age, sex, vascular risk, physical functioning, antidepressants and infarcts. We adjusted for CSVD to examine whether it may be an intermediate or confounding factor. Second, we added interaction terms to investigate whether associations differed between patients with CSVD (absent/present).

RESULTS

Patients in the lowest quartile of mental functioning, representing most severe mood problems, were at higher, although not significant, risk of death (hazard ratio [HR] = 1.47, 95% confidence interval [CI] = 0.94-2.30) compared with patients in higher quartiles. Adjustment for CSVD did not change this association. Lacunar infarcts, not WML, modified the association of mood problems with mortality (p value for interaction = .01); mood problems strongly increased the risk of mortality in patients with lacunar infarcts (HR = 2.75, 95% CI = 1.41-5.38) but not in those without it (HR = 0.78, 95% CI = 0.39-1.57).

CONCLUSIONS

Patients with lacunar infarcts may be especially vulnerable for the effect of mood problems on mortality.

Cortical plasticity is preserved in nondemented older individuals with severe ischemic small vessel disease

Ischemic small vessel disease (SVD) is a common finding on routine scans in older people, but cognitive sequelae vary considerably. To improve understanding of mechanisms underlying decline or preservation of cognitive function in this condition, we assessed cognition and cortical plasticity in 20 elderly subjects with severe SVD and 20 age-matched controls without SVD, as rated on conventional MRI. Cognitive status was determined with a neuropsychological test battery, cortical plasticity induced with a paired associative stimulation protocol. Microstructural white matter changes were further analyzed for fractional anisotrophy using diffusion tensor imaging. We found that cortical plasticity as well as memory functions were preserved in severe SVD, while executive functions showed trendwise or significant decreases. Within the SVD group, lower white matter integrity in parahippocampal regions and posterior parts of the corpus callosum was associated with larger cortical plasticity, an association not seen for prefrontal white matter tracts. Enhanced cortical plasticity in subjects with lower white matter integrity in memory-relevant areas might thus indicate a compensatory mechanism to counteract memory decline in severe SVD.

Depression, hypothalamic pituitary adrenal axis, and hippocampal and entorhinal cortex volumes--the SMART Medea study

BACKGROUND

Structural brain changes have often been found in major depressive disorder (MDD), and it is thought that hypothalamic-pituitary-adrenal (HPA) axis hyperactivity may explain this relation. We investigated the association of MDD and history of depression with hippocampal and entorhinal cortex volumes and whether HPA axis activity explained this association.

METHODS

In 636 participants with a history of atherosclerotic disease (mean age 62 ± 9 years, 81% male) from the second Manifestation of ARTerial disease-Memory depression and aging (SMART-Medea) study, a 12-month diagnosis of MDD and history of depression were assessed. Age of first depressive episode was classified into early-onset depression (< 50 years) and late-onset depression (≥ 50 years). HPA axis regulation was assessed by four morning saliva samples, two evening samples, and one awakening sample after .5 mg dexamethasone. Hippocampus and entorhinal cortex volume were manually outlined on three-dimensional T1-weighted magnetic resonance images.

RESULTS

General linear models adjusted for demographics, vascular risk, antidepressant use, and white matter lesions showed that ever having had MDD was associated with smaller hippocampal volumes but not with entorhinal cortex volumes. Remitted MDD was related to smaller entorhinal cortex volumes (p < .05). Participants with early-onset depression had smaller hippocampal volumes than those who were never depressed (p < .05), whereas participants with late-onset depression had smaller entorhinal cortex volumes (p < .05). HPA axis activity did not explain these differences.

CONCLUSIONS

We found differential associations of age of onset of depression on hippocampal and entorhinal cortex volumes, which could not be explained by alterations in HPA axis regulation.

An MRI-based semiquantitative index for the evaluation of brain atrophy and lesions in Alzheimer's disease, mild cognitive impairment and normal aging

BACKGROUND

This study investigates how T(1)-weighted MRI can be used to evaluate brain anatomical changes. We investigated these changes in Alzheimer's disease (AD) and normal aging.

METHODS

A semiquantitative brain atrophy and lesion index (BALI) was constructed by adapting existing visual rating scales and validated in 3 datasets.

RESULTS

The T(1)- and T(2)-weighted-imaging-based scores were highly correlated. They were both closely associated with age and with cognitive test scores.

CONCLUSION

The T(1)-based BALI helps describe brain structural variability in AD, mild cognitive impairment and normal aging.

Hepatocyte growth factor is a significant risk factor for white matter lesions in Japanese type 2 diabetic patients

BACKGROUND

The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. Elevated hepatocyte growth factor (HGF) levels are associated with a high mortality rate in type 2 diabetic patients. The preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with HGF and insulin resistance in type 2 diabetic patients not receiving insulin treatment.

MATERIAL AND METHODS

Based on brain magnetic resonance imaging, 92 type 2 diabetic patients were divided into two groups: WML-positive group (age 60 +/- 5 years, mean +/- SD, n = 35) and WML-negative group (age 59 +/- 6 years, mean +/- SD, n = 57. The level of blood glucose was assessed by fasting plasma glucose, fasting immunoreactive insulin, homeostasis model assessment (HOMA) index and haemoglobin A1c (HbA1c).

RESULTS

The body mass index was higher in the WML-positive group than that in the WML-negative group (P < 0.005). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol was lower in the WML-positive group than in the WML-negative group (P < 0.01 and P < 0.0001 respectively). Fasting plasma glucose (P < 0.0001), insulin concentrations (P < 0.0001), HOMA index (P < 0.0001) and HGF (< 0.0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the high HGF and insulin resistance (P < 0.0001 and P < 0.0001 respectively).

CONCLUSION

The results of this preliminary study indicate that the presence of WML was associated with the high HGF and insulin resistance in Japanese patients with type 2 diabetes mellitus.

Advances in imaging 2009

Imaging remains a mainstay of stroke diagnosis and treatment. 2009 brought much that was new: increased scrutiny of the safety of imaging; evidence of improved technical capabilities of imaging; new findings based on imaging; and as a result of the above, evidence that the field has definite needs. We will briefly cover each of these in turn.