Decreased hemoglobin levels, cerebral small-vessel disease, and cortical atrophy: among cognitively normal elderly women and men.

BACKGROUND: Decreased hemoglobin levels increase the risk of developing dementia among the elderly. However, the underlying mechanisms that link decreased hemoglobin levels to incident dementia still remain unclear, possibly due to the fact that few studies have reported on the relationship between low hemoglobin levels and neuroimaging markers. We, therefore, investigated the relationships between decreased hemoglobin levels, cerebral small-vessel disease (CSVD), and cortical atrophy in cognitively healthy women and men. METHODS: Cognitively normal women (n = 1,022) and men (n = 1,018) who underwent medical check-ups and magnetic resonance imaging (MRI) were enrolled at a health promotion center. We measured hemoglobin levels, white matter hyperintensities (WMH) scales, lacunes, and microbleeds. Cortical thickness was automatically measured using surface based methods. Multivariate regression analyses were performed after controlling for possible confounders. RESULTS: Decreased hemoglobin levels were not associated with the presence of WMH, lacunes, or microbleeds in women and men. Among women, decreased hemoglobin levels were associated with decreased cortical thickness in the frontal (Estimates, 95% confidence interval, -0.007, (-0.013, -0.001)), temporal (-0.010, (-0.018, -0.002)), parietal (-0.009, (-0.015, -0.003)), and occipital regions (-0.011, (-0.019, -0.003)). Among men, however, no associations were observed between hemoglobin levels and cortical thickness. CONCLUSION: Our findings suggested that decreased hemoglobin levels affected cortical atrophy, but not increased CSVD, among women, although the association is modest. Given the paucity of modifiable risk factors for age-related cognitive decline, our results have important public health implications.

Neovascularization precedes occlusion in moyamoya disease: angiographic findings in 172 pediatric patients.

BACKGROUND: Both basal collaterals (BC) and cortical microvascularization (CM) on angiography have been suggested as moyamoya disease (MMD)-specific findings; however, it is unknown whether the vascular network represents compensatory mechanisms for vascular occlusion or aberrant active neovascularization. METHODS: We investigated the grade of antegrade MCA flow, the degree of BC, and the presence of CM on conventional angiography in relation to disease severity in pediatric MMD. CM was defined as enlarged and winding distal cortical arteries and categorized into anterior or posterior CM depending on their sources. Findings from basal and acetazolamide stress brain perfusion SPECT studies were also evaluated. RESULTS: A total of 172 pediatric patients with MMD were enrolled in this study. As the severity of MMD increased, the grade of antegrade MCA flow gradually diminished. While the degree of BC peaked at Suzuki stage 3-4, CM was frequently observed at early MMD stages. About two-thirds of hemispheres with normal antegrade MCA flow on angiography and normal perfusion status on SPECT had anterior and/or posterior CM. Both anterior and posterior CM gradually decreased with the advancement of MMD. CONCLUSION: Our findings from a large cohort of angiographically confirmed pediatric MMD patients indicate that neovascularization may occur before significant hemodynamic impairment in MMD.

Psychiatric symptoms in myoclonus-dystonia syndrome are just concomitant features regardless of the SGCE gene mutation.

INTRODUCTION: Among myoclonus-dystonia syndrome (MD) patients, psychiatric disorders including depression, anxiety, alcohol dependence, obsessive-compulsive disorder (OCD) and panic disorder have been frequently reported to be related with the epsilon-sarcoglycan gene (SGCE) mutation. However, the rate of psychiatric disorders has not been compared between MD patients with the SGCE mutation (SGCE (+)) and without the SGCE mutation (SGCE (-)). We analyzed the psychiatric data in both SGCE (+) and SGCE (-) MD patients to determine the association of the SGCE mutation with psychiatric disorders in MD. METHODS: Twenty-six MD patients who fulfilled the Grunewald's criteria and underwent a SGCE gene study were enrolled. Patients were divided into two groups according to their SGCE status (SGCE (+) and SGCE (-) group). They were systematically assessed using a standardized protocol including motor severity scales and psychiatric questionnaires for depression, anxiety, alcohol dependence, OCD and panic disorder. RESULTS: Fifteen SGCE (+) and eleven SGCE (-) patients were enrolled. Mean age at onset, disease duration, family history, alcohol responsiveness and motor severity were not different between the SGCE (+) and SGCE (-) group. Although more than half (53.8%) of all the MD patients had psychiatric symptoms, there were no significant differences between the SGCE (+) and SGCE (-) group in terms of their psychiatric questionnaire scores and rate of psychiatric disorders. CONCLUSIONS: Psychiatric features are not likely to be related with the SGCE mutation itself but just bespeak disability in clinical MD syndrome regardless of the SGCE mutation.

Alterations of mean diffusivity of pedunculopontine nucleus pathway in Parkinson's disease patients with freezing of gait.

BACKGROUND: Although freezing of gait (FOG) is a common and disabling symptom in Parkinson's disease (PD), the underlying mechanism of FOG has not been clearly elucidated. Using analysis of diffusion tensor imaging (DTI), we investigated anatomic structures associated with FOG in PD patients. METHODS: We enrolled 33 controls and 42 PD patients (19 patients with FOG and 23 without FOG). DTI data were compared between PD patients and controls, and also between PD patients with and without FOG. Whole brain voxel-based analysis and regions of interest analysis in the pedunculopontine nucleus were used for DTI analysis. RESULTS: Compared with normal controls, PD patients showed microstructural changes in various subcortical structures (substantia nigra, globus pallidum and thalamus), frontal and insula cortex. PD patients with FOG demonstrated altered mean diffusivities in subcortical structures connected with pedunculopontine nucleus, such as basal ganglia, thalamus and cerebellum in voxel-based analysis. Using region of interest analysis of pedunculopontine nucleus, fractional anisotropy values were reduced and mean diffusivity values were increased bilaterally in PD patients with FOG. In correlation analysis, the fractional anisotropy value of the right pedunculopontine nucleus was moderately correlated with the severity of FOG. CONCLUSIONS: Based on our results, microstructural changes of pedunculopontine nucleus and connected subcortical structures are closely related with FOG in PD patients.

Non-Ataxic Phenotypes of SCA8 Mimicking Amyotrophic Lateral Sclerosis and Parkinson Disease.

BACKGROUND: Spinocerebellar ataxia (SCA) type 8 (SCA8) is an inherited neurodegenerative disorder caused by the expansion of untranslated CTA/CTG triplet repeats on 13q21. The phenomenology of SCA8 is relatively varied when compared to the other types of SCAs and its spectrum is not well established. CASE REPORT: Two newly detected cases of SCA8 with the nonataxic phenotype and unusual clinical manifestations such as dopaminergic-treatment-responsive parkinsonism and amyotrophic lateral sclerosis (ALS) are described herein. Family A expressed good dopaminergic treatment-responsive parkinsonism as an initial manifestation and developed mild cerebellar ataxia with additional movements, including dystonic gait and unusual oscillatory movement of the trunk, during the disease course. The proband of family B presented as probable ALS with cerebellar atrophy on brain MRI, with a positive family history (a brother with typical cerebellar ataxia) and genetic confirmation for SCA8. CONCLUSIONS: Our findings support that the non-ataxic phenotypes could be caused by a mutation of the SCA8 locus which might affect neurons other than the cerebellum.