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Growing evidence suggests that neuroinflammation plays a critical role in the pathogenesis of neurodegenerative diseases. Peripheral markers of inflammation, including blood cell counts and their ratios, such as the neutrophil-to-lymphocyte ratio (NLR), have been reported as an easily accessible and reliable proxy of central nervous system inflammation. However, the role of peripheral inflammation in dementia and Mild Cognitive Impairment (MCI) still needs to be clarified. In the current study, we aimed to assess the prognostic role of the NLR and other peripheral markers of inflammation in a sample of 130 amnestic MCI, followed up for two to five years. The Mini-Mental state examination (MMSE) score at baseline and follow-up visits was used to assess global cognitive status at each visit and the degree of cognitive decline over time. Baseline peripheral markers of inflammation included blood cell counts and ratios, specifically the NLR, the platelet-to-lymphocyte ratio (PLR), the monocyte-to-lymphocyte ratio (MLR), and the systemic immune inflammation index (SII). After classifying subjects into CONVERTERS and non-CONVERTERS (respectively, patients converting to dementia and subjects showing stability at the last available follow-up), we compared peripheral markers of inflammation among groups ed correlated them with cognitive measures, testing the ability of significant factors to predict conversion to dementia. In our cohort, CONVERTERS showed lower baseline MMSE scores (p-value = 0.004) than non-CONVERTERS. In addition, CONVERTERS had statistically elevated NLR (p-value = 0.005), PLR (p-value = 0.002), and SII levels (p-value = 0.015), besides a lower number of lymphocytes (p-value = 0.004) compared with non-CONVERTERS. In a logistic regression analysis, baseline MMSE scores and NLR predicted conversion to dementia. Tertiles analysis showed that MCI with the highest NLR values had a higher conversion risk. Our study supports the hypothesis that a dysregulation of peripheral inflammation involving both lymphocytes and neutrophils may play a role in the pathogenesis of dementia, even at the early stages of neurodegeneration, as in the MCI condition. [ABSTRACT FROM AUTHOR]

Background: Non-invasive biomarkers of cognitive impairment are needed. We aim to evaluate transcranial sonographic markers as predictors of cognitive impairment in a prospective cohort.Objective: To study the changes in the third ventricle diameter and the SN echogenicity between the baseline and the control visit, as well as its association with cognitive performance and the diagnosis of cognitive impairment in a prospective cohort.Methods: From the longitudinal population-based Asymptomatic Intracranial Atherosclerosis Study, we selected those subjects that received a complete transcranial sonography (TCS) and extensive cognitive testing, both at baseline and follow-up. We evaluated third ventricle (IIIv) width, echogenicity of substantia nigra (SN), and temporal changes of these parameters.Results: We included 289 participants with a median follow-up time of 7.16 years. Those subjects who developed cognitive decline (n = 23, 7.96%) had a larger IIIv at baseline than those who did not (0.54±0.14 cm versus 0.41±0.15 cm; p = 0.001). A cut-off point of 0.465 cm for the IIIv width was identified as an independent predictor of long-term cognitive impairment after adjustment for age, gender, educational level, and vascular risk score. Change in IIIv diameter after follow-up was not associated with diagnosis of cognitive impairment. The area of SN and the presence of hyperechogenicity of the SN remained stable over time and was not associated with the diagnosis of cognitive impairment.Conclusion: IIIv width assessed by TCS emerged as an independent predictor of long-term cognitive impairment. [ABSTRACT FROM AUTHOR]

The association of cerebral white matter lesions (WMLs) with cognitive status is not well understood in middle-aged individuals. Our aim was to determine the specific contribution of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) to cognitive function in a community sample of asymptomatic participants aged 50 to 65 years. One hundred stroke- and dementia-free adults completed a comprehensive neuropsychological battery and brain MRI protocol. Participants were classified according to PVH and DWMH scores (Fazekas scale). We dichotomized our sample into low grade WMLs (participants without or with mild lesions) and high grade WMLs (participants with moderate or severe lesions). Analyses were performed separately in PVH and DWMH groups. High grade DWMHs were associated with significantly lower scores in executive functioning (−0.45 standard deviations [SD]), attention (−0.42 SD), verbal fluency (−0.68 SD), visual memory (−0.52 SD), visuospatial skills (−0.79 SD), and psychomotor speed (−0.46 SD). Further analyses revealed that high grade DWMHs were also associated with a three- to fourfold increased risk of impaired scores (i.e.,<1.5 SD) in executive functioning, verbal fluency, visuospatial skills, and psychomotor speed. Our findings suggest that only DWMHs, not PVHs, are related to diminished cognitive function in middle-aged individuals. (JINS, 2012, 18, 1–12) [ABSTRACT FROM PUBLISHER]