The pattern of cognitive performance in CADASIL: A monogenic condition leading to subcortical ischemic vascular dementia
ABSTRACT Subcortical ischemic vascular lesions, which are closely related to small vessel disease, are a common substrate of cognitive impairment and dementia. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic variant of small vessel disease resulting from mutations in NOTCH3. Mutation carriers almost invariably develop cognitive deficits and eventually dementia. The current study describes the profile of cognitive abnormalities in CADASIL subjects.
A cross-sectional study of 65 mutation carriers (mean age=47.3 years, SD=10.5) and 30 matched comparison subjects (mean age=47.2 years, SD=14.0) was conducted. Participants underwent a series of assessments that included ratings of global cognition, the cognitive portion of the Vascular Dementia Assessment Scale, and specific tests of executive function and attention with measures of processing speed and error monitoring.
CADASIL subjects had pronounced impairments of the timed measures (Stroop II and III, Trail Making Test, symbol digit, digit cancellation). Measures of error monitoring (Stroop III, Trail Making Test, symbol digit, maze task) were also significantly affected but to a lesser extent. Prominent deficits further included verbal fluency and ideational praxis. Recall, orientation, and receptive language skills were largely preserved. Subgroup analyses indicated a similar profile in subjects with early and advanced impairment of global cognitive performance.
The findings highlight processing speed as the most substantial area of cognitive impairment in CADASIL subjects, with less pronounced yet significant deficits in other aspects of executive performance and attention. This profile of cognitive impairment is present at an early stage and enables the construction of targeted test batteries for clinical trials. It is hypothesized that the profile of dysfunction described here represents the core of the cognitive syndrome associated with small vessel disease and subcortical ischemic vascular lesions.
Article: CADASIL and CARASIL[Show abstract] [Hide abstract]
ABSTRACT: CADASIL and CARASIL are hereditary small vessel diseases leading to vascular dementia. CADASIL commonly begins with migraine followed by minor strokes in mid-adulthood. Dominantly inherited CADASIL is caused by mutations (n > 230) in NOTCH3 gene, which encodes Notch3 receptor expressed in vascular smooth muscle cells (VSMC). Notch3 extracellular domain (N3ECD) accumulates in arterial walls followed by VSMC degeneration and subsequent fibrosis and stenosis of arterioles, predominantly in cerebral white matter, where characteristic ischemic MRI changes and lacunar infarcts emerge. The likely pathogenesis of CADASIL is toxic gain of function related to mutation-induced unpaired cysteine in N3ECD. Definite diagnosis is made by molecular genetics but is also possible by electron microscopic demonstration of pathognomonic granular osmiophilic material at VSMCs or by positive immunohistochemistry for N3ECD in dermal arteries.In rare, recessively inherited CARASIL the clinical picture and white matter changes are similar as in CADASIL, but cognitive decline begins earlier. In addition, gait disturbance, low back pain and alopecia are characteristic features. CARASIL is caused by mutations (presently n = 10) in high-temperature requirement. A serine peptidase 1 (HTRA1) gene, which result in reduced function of HTRA1 as repressor of transforming growth factor-β (TGF β) -signaling. Cerebral arteries show loss of VSMCs and marked hyalinosis, but not stenosis.Brain Pathology 09/2014; 24(5). DOI:10.1111/bpa.12181 · 4.35 Impact Factor
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ABSTRACT: Patients with unilateral occlusive processes of the internal carotid artery (ICA) show subtle cognitive deficits. Decline in cerebral autoregulation and in functional and structural integrity of brain networks have previously been reported in the affected hemisphere (AH). However, the association between cerebral autoregulation, brain networks, and cognition remains to be elucidated. Fourteen neurologically asymptomatic patients (65±11 years) with either ICA occlusion or high-grade ICA stenosis and 11 age-matched healthy controls (HC) (67±6 years) received neuropsychologic testing, transcranial Doppler sonography to assess cerebral autoregulation using vasomotor reactivity (VMR), and magnetic resonance imaging to probe white matter microstructure and resting-state functional connectivity (RSFC). Patients performed worse on memory and executive tasks when compared with controls. Vasomotor reactivity, white matter microstructure, and RSFC were lower in the AH of the patients when compared with the unaffected hemisphere and with controls. Lower VMR of the AH was associated with several ipsilateral clusters of lower white matter microstructure and lower bilateral RSFC in patients. No correlations were found between VMR and cognitive scores. In sum, impaired cerebral autoregulation was associated with reduced structural and functional connectivity in cerebral networks, indicating possible mechanisms by which severe unilateral occlusive processes of the ICA lead to cognitive decline.Journal of Cerebral Blood Flow & Metabolism advance online publication, 12 November 2014; doi:10.1038/jcbfm.2014.190.Journal of Cerebral Blood Flow & Metabolism 11/2014; 35(2). DOI:10.1038/jcbfm.2014.190 · 5.34 Impact Factor
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ABSTRACT: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is an autosomal dominant vascular disorder. Diagnosis and follow-up in patients with CADASIL are based mainly on magnetic resonance imaging (MRI). MRI shows white matter hyperintensities (WMHs), lacunar infarcts and cerebral microbleeds (CMBs). WMHs lesions tend to be symmetrical and bilateral, distributed in the periventricular and deep white matter. The anterior temporal lobe and external capsules are predilection sites for WMHs, with higher specificity and sensitivity of anterior temporal lobe involvement compared to an external capsule involvement. Lacunar infarcts are presented by an imaging signal that has intensity of cerebrospinal fluid in all MRI sequences. They are localized within the semioval center, thalamus, basal ganglia and pons. CMBs are depicted as focal areas of signal loss on T2 images which increases in size on the T2*-weighted gradient echo planar images ("blooming effect").Bosnian journal of basic medical sciences / Udruzenje basicnih mediciniskih znanosti = Association of Basic Medical Sciences 01/2015; 15(1):1-8. DOI:10.17305/bjbms.2015.1.247 · 0.41 Impact Factor