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White matter hyperintensities (WMH) are the most common brain-imaging feature of cerebral small vessel disease (SVD), hypertension being the main known risk factor. Here, we identify 27 genome-wide loci for WMH-volume in a cohort of 50,970 older individuals, accounting for modification/confounding by hypertension. Aggregated WMH risk variants were associated with altered white matter integrity (p=2.5x10-7) in brain images from 1,738 young healthy adults, providing insight into the lifetime impact of SVD genetic risk. Mendelian randomization suggested causal association of increasing WMH-volume with stroke, Alzheimer-type dementia, and of increasing blood pressure (BP) with larger WMH-volume, notably also in persons without clinical hypertension. Transcriptome-wide colocalization analyses showed association of WMH-volume with expression of 39 genes, of which four encode known drug targets. Finally, we provide insight into BP-independent biological pathways underlying SVD and suggest potential for genetic stratification of high-risk individuals and for genetically-informed prioritization of drug targets for prevention trials. White matter hyperintensities (WMH) are a common brain-imaging feature of cerebral small vessel disease. Here, the authors carry out a GWAS and followup analyses for WMH-volume, implicating several variants with potential for risk stratification and drug targeting.

Although white matter lesions are frequently detected in migraine patients, underlying mechanisms remain unclear. Low carotid artery endothelial shear stress has been associated with white matter lesions. We aimed to investigate the association between carotid artery endothelial shear stress and white matter lesions in migraine. In 40 elderly migraine patients ( n = 29 females, 75 years [SD 3]) and 219 controls ( n = 80 females, 74 years [SD 3]) from the PROSPER-MRI study, carotid artery endothelial shear stress was estimated on 1.5 T gradient-echo phase contrast MRI. White matter lesion volumes were calculated from structural MRI scans. Analyses were adjusted for age, sex, cardiovascular risk factors and cardiovascular disease. Migraine patients had lower mean endothelial shear stress compared to controls (0.90 [SD 0.15] vs. 0.98 [SD 0.16] Pa; P = 0.03). The association between mean endothelial shear stress and white matter lesion volume was greater for the migraine group than control group ( P for interaction = 0.05). Within the migraine group, white matter lesion volume increased with decreasing endothelial shear stress (β-0.421; P = 0.01). In conclusion, migraine patients had lower endothelial shear stress which was associated with higher white matter lesion volume.

Objectives: Previous research has demonstrated an association between emotion recognition and apathy in several neurological conditions involving fronto-striatal pathology, including Parkinson’s disease and brain injury. In line with these findings, we aimed to determine whether apathetic participants with early Huntington’s disease (HD) were more impaired on an emotion recognition task compared to non-apathetic participants and healthy controls. Methods: We included 43 participants from the TRACK-HD study who reported apathy on the Problem Behaviours Assessment – short version (PBA-S), 67 participants who reported no apathy, and 107 controls matched for age, sex, and level of education. During their baseline TRACK-HD visit, participants completed a battery of cognitive and psychological tests including an emotion recognition task, the Hospital Depression and Anxiety Scale (HADS) and were assessed on the PBA-S. Results: Compared to the non-apathetic group and the control group, the apathetic group were impaired on the recognition of happy facial expressions, after controlling for depression symptomology on the HADS and general disease progression (Unified Huntington’s Disease Rating Scale total motor score). This was despite no difference between the apathetic and non-apathetic group on overall cognitive functioning assessed by a cognitive composite score. Conclusions: Impairment of the recognition of happy expressions may be part of the clinical picture of apathy in HD. While shared reliance on frontostriatal pathways may broadly explain associations between emotion recognition and apathy found across several patient groups, further work is needed to determine what relationships exist between recognition of specific emotions, distinct subtypes of apathy and underlying neuropathology. (JINS, 2019, 25, 453–461)

Background and Purpose— Low wall shear stress (WSS) is an early marker in the development of vascular lesions. The present study aims to assess the relationship between diastolic and systolic WSS in the internal carotid artery and periventricular (PWML), deep white matter lesions, and cerebral infarcts (CI). Methods— Early, mid, and late diastolic and peak systolic WSS were derived from shear rate obtained by gradient echo phase contrast magnetic resonance sequences multiplied by individually modeled viscosity. PWML, deep white matter lesions, and CI were derived from proton density (PD), T2, and fluid attenuated inversion recovery (FLAIR) MRI in 329 participants (70–82 years; PROSPER baseline). Analyses were adjusted, if appropriate, for age, gender, intracranial volume, and multiple cardiovascular risk factors. Results— Mid-diastolic WSS was significantly correlated with the presence of PWML (B=−10.15; P =0.006) and CI (B=−2.06; P =0.044), but not with deep white matter lesions (B=−1.30; P =0.050; adjusted for age, gender, WML, and intracranial volume). After adjustment for cardiovascular risk factors, these correlations weakened but remained significant. Systolic WSS was not correlated with any of the cerebrovascular parameters. Conclusions— This study is the first to our knowledge to present a cross-sectional correlation between carotid artery WSS and cerebrovascular pathology such as PWML and CI in a large population. Furthermore, it shows that diastolic hemodynamics may be more important than systolic or mean hemodynamics. Future studies exploring vascular hemodynamic damage should focus on diastolic WSS.

Background and Purpose— Migraine is a risk factor for clinical stroke and for subclinical white matter hyperintensities and infratentorial infarcts. These subclinical lesions are linked to small-vessel pathology. Cerebral microbleeds (CMBs) are another biomarker of small-vessel disease but have not yet been studied in migraine. Methods— Identification of CMBs in 63 migraineurs (25 with aura/35 without aura/3 unknown aura status) and 359 controls (aged, 73–85 years) from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) magnetic resonance imaging study. We assessed the modifying role of migraine in the co-occurrence of CMBs, infarcts, and white matter hyperintensity-load. Results— Infratentorial microbleeds were more prevalent in migraine without aura patients than controls (14% versus 4%). Prevalence of other CMBs, infarcts, and white matter hyperintensities did not differ between groups. Migraineurs with CMBs had more often infarcts than controls with CMBs (65% versus 43%). In comparison with controls with infarcts, migraineurs with infarcts had more commonly CMBs (55% versus 30%). Conclusions— Migraine, notably without aura, is associated with infratentorial CMBs at older age. CMBs and infarcts co-occur more often in migraine than in controls. This supports the hypothesis of small-vessel involvement in migraine pathophysiology.

Objectives: Cerebral microbleeds (MBs) are an important indicator of cerebral small-vessel disease, and their prevalence increases with increasing age. Little is known about the functional consequences of MBs in the aging population. In this study we investigated whether the presence and location of MBs are associated with cognition in the PROSPER study. Methods: For 439 subjects the number and location (cortico-subcortical, deep white matter, basal ganglia, and infratentorial) of the MBs was recorded. Difference in cognitive performance between subjects with and without MBs was calculated by entering the variables sex, age, white matter hyperintensity volume, infarction, and MBs in a linear mixed model. Differences in cognition between subjects with and without one or more MBs at different anatomic locations were assessed using the same model. Results: We found that after correction for sex, age, white matter hyperintensity volume, and infarction, subjects with infratentorial MBs had a significantly lower score on the Immediate Picture-Word Learning test, Delayed Picture-Word Learning, and Instrumental Activities of Daily Living. Conclusions: Our data demonstrate that in elderly individuals at increased vascular risk, infratentorial MBs are associated with loss in cognitive functioning.

Background: The basal ganglia, hippocampus, and thalamus are involved in the regulation of human feeding behavior. Recent studies have shown that obesity [body mass index (BMI; in kg/m(2)) > 30] is associated with loss of gray and white matter. Objective: It is unknown whether the subcortical brain structures that are actually involved in feeding behavior also show volume changes in obesity. Therefore, the purpose of this study was to evaluate the volumes of the basal ganglia, hippocampus, and thalamus in obesity. Design: Three-dimensional T1-weighted magnetic resonance imaging scans of the brain were analyzed by using automatic segmentation to measure volumes of the nucleus accumbens, globus pallidus, amygdala, putamen, caudate nucleus, thalamus, and hippocampus in 471 subjects (mean age: 74.4 y; 56% men). Results: Obese subjects had larger left (P = 0.013) and right (P = 0.003) amygdalar volumes and a larger left hippocampal volume (P = 0.040) than did normal-weight subjects (BMI, 25). None of the other subcortical structures differed in size between these groups. After correction for age, sex, smoking, hypertension, and pravastatin use, BMI was associated with left (beta = 0.175, P = 0.001) and right (beta = 0.157, P = 0.001) amygdalar volumes and with left hippocampal volume (beta = 0.121, P = 0.016). Conclusions: This study showed that the amygdala and hippocampus are enlarged in obesity. In consideration of the function of these structures, this finding may indicate that hedonic memories could be of major importance in the regulation of feeding. Because of the cross-sectional design, cause and effect could not be discriminated in this study. Am J Clin Nutr 2011;93:1190-5.

In Huntington’s disease (HD) atrophy of the caudate nucleus and putamen has been described many years before clinical manifestation. Volume changes of the pallidum, thalamus, brainstem, accumbens nucleus, hippocampus, and amygdala are less well investigated, or reported with contradicting results. The aim of our study is to provide a more precise view of the specific atrophy of the subcortical grey matter structures in different stages of Huntington’s disease, and secondly to investigate how this influences the clinical manifestations. All TRACK-HD subjects underwent standardised T1-weighted 3T MRI scans encompassing 123 manifest HD (stage 1, n = 77; stage 2, n = 46), 120 premanifest HD (close to onset n = 58, far from onset n = 62) and 123 controls. Using FMRIB’s FIRST and SIENAX tools the accumbens nucleus, amygdala, brainstem, caudate nucleus, hippocampus, pallidum, putamen, thalamus and whole brain volume were extracted. Results showed that volumes of the caudate nucleus and putamen were reduced in premanifest HD far from predicted onset (>10.8 years). Atrophy of accumbens nucleus and pallidum was apparent in premanifest HD in the close to onset group (0–10.8 years). All other structures were affected to some degree in the manifest group, although brainstem, thalamus and amygdala were relatively spared. The accumbens nucleus, putamen, pallidum and hippocampus had a strong significant correlation with functional and motor scores. We conclude that volume changes may be a sensitive and reliable measure for early disease detection and in this way serve as a biomarker for Huntington’s disease. Besides the caudate nucleus and putamen, the pallidum and the accumbens nucleus show great potential in this respect. Electronic supplementary material The online version of this article (doi:10.1007/s00415-010-5768-0) contains supplementary material, which is available to authorized users.

BACKGROUND AND PURPOSE: Although total cerebral blood flow (tCBF) is known to be related to age, less is known regarding the associations between tCBF and the morphologic changes of the brain accompanying cerebral aging. The purpose of this study was to investigate whether total cerebral blood flow (tCBF) is related to white matter hyperintensity (WMH) volume and/or cerebral atrophy. Furthermore, we investigate whether tCBF should be expressed in mL/min, as was done in all previous MR studies, or in mL/100 mL/min, which yielded good results in precious SPECT, PET and perfusion MRI studies investigating regional cerebral blood flow. MATERIALS AND METHODS: Patients were included from the nested MRI sub-study of the PROSPER study. Dual fast spin echo and FLAIR images were obtained in all patients. In addition, single slice phase contrast MR angiography was used for flow measurements in the internal carotids and vertebral arteries. tCBF was expressed in both mL/min and mL/100 mL/min. RESULTS: We found a significant correlation between tCBF in mL/min and both age (r = -.124; p = p