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Background: The hippocampus, entorhinal cortex, and basal forebrain are among the first brain structures affected by Alzheimer's disease (AD). They play an essential role in spatial pattern separation, a process critical for accurate encoding of similar spatial information.Objective: Our aim was to examine spatial pattern separation and its association with volumetric changes of the hippocampus, entorhinal cortex, and basal forebrain nuclei projecting to the hippocampus (the medial septal nuclei and vertical limb of the diagonal band of Broca - Ch1-2 nuclei) in the biomarker-defined early clinical stages of AD.Methods: A total of 98 older adults were recruited from the Czech Brain Aging Study cohort. The participants with amnestic mild cognitive impairment (aMCI) due to AD (n = 44), mild AD dementia (n = 31), and cognitively normal older adults (CN; n = 23) underwent spatial pattern separation testing, comprehensive cognitive assessment, and MRI brain volumetry.Results: Spatial pattern separation accuracy was lower in the early clinical stages of AD compared to the CN group (p < 0.001) and decreased with disease severity (CN > aMCI due to AD > AD dementia). Controlling for general memory and cognitive performance, demographic characteristics and psychological factors did not change the results. Hippocampal and Ch1-2 volumes were directly associated with spatial pattern separation performance while the entorhinal cortex operated on pattern separation indirectly through the hippocampus.Conclusion: Smaller volumes of the hippocampus, entorhinal cortex, and basal forebrain Ch1-2 nuclei are linked to spatial pattern separation impairment in biomarker-defined early clinical AD and may contribute to AD-related spatial memory deficits. [ABSTRACT FROM AUTHOR]

The goal was to provide an overview of main issues relevant to aging in the Czech Republic. The Czech Republic is a former Eastern Bloc nation of about 10.5 million. Older adults are overrepresented relative to those under age 15. Life expectancy currently hovers around 78 years (75 for men/81 for women), a number slightly higher than most of Eastern Europe but lower than most of Western Europe. Cardiovascular diseases account for about 50% of all mortality, which is one of the highest rates in Europe and therefore of particular concern. Lifestyle habits, especially high alcohol consumption, a high rate of smokers, and high-fat diet relative to most other European countries and the United States, combined with relatively low expenditures for health promotion, appear important in the context of high cardiovascular mortality. Long-term care is funded mostly by state and local governments. The country has tried to address issues associated with insufficient capacity and low quality in long-term care, a particularly prominent problem in the Czech Republic compared with other European countries. The recently established International Clinical Research Center brings new possibilities for collaborative research in the Czech Republic, including research specific to aging. Improving long-term care and establishing methodologically sound longitudinal data sets are among the most pressing issues, although sustaining the pension system strained by increasing life expectancy, low retirement age, and extensive government-sponsored benefits has also recently emerged as a critical issue. [ABSTRACT FROM PUBLISHER]

Background Depressive symptoms are common among older adults, particularly those living in long-term care facilities. However, little is known about factors associated with depressive symptoms among long-term care residents in the Czech Republic and in other Eastern European countries. Moreover, the role of mobility and pain in depressive symptoms among long-term care residents is relatively understudied. Objective We examined the relationship between functional status and depressive symptoms in 308 older adults from residential care facilities (RCFs) in the Czech Republic. Method We used baseline data from two randomized controlled trials testing the effects of dance and reminiscence therapies on quality of life in older RCF residents. Functional status was measured as cognitive function, general ability to perform basic Activities of Daily Living (ADLs), mobility, and functional limitation by pain. Depressive symptoms were measured using the 15-item Geriatric Depression Scale. Results In multiple regression analyses adjusted for sociodemographic factors and taking antidepressants, we found that cognitive function and functional limitation by pain were most strongly associated with depressive symptoms. The ability to perform basic ADLs and mobility were also related to depressive symptoms. Conclusion Our findings suggest factors that may be important in efforts to improve psychological well-being in this population. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To compare cognitive phenotypes of participants with subjective cognitive decline (SCD) and amnestic mild cognitive impairment (aMCI), estimate progression to MCI/dementia by phenotype and assess classification error with machine learning., Method: Dataset consisted of 163 participants with SCD and 282 participants with aMCI from the Czech Brain Aging Study. Cognitive assessment included the Uniform Data Set battery and additional tests to ascertain executive function, language, immediate and delayed memory, visuospatial skills, and processing speed. Latent profile analyses were used to develop cognitive profiles, and Cox proportional hazards models were used to estimate risk of progression. Random forest machine learning algorithms reported cognitive phenotype classification error., Results: Latent profile analysis identified three phenotypes for SCD, with one phenotype performing worse across all domains but not progressing more quickly to MCI/dementia after controlling for age, sex, and education. Three aMCI phenotypes were characterized by mild deficits, memory and language impairment (dysnomic aMCI), and severe multi-domain aMCI (i.e., deficits across all domains). A dose-response relationship between baseline level of impairment and subsequent risk of progression to dementia was evident for aMCI profiles after controlling for age, sex, and education. Machine learning more easily classified participants with aMCI in comparison to SCD (8% vs. 21% misclassified)., Conclusions: Cognitive performance follows distinct patterns, especially within aMCI. The patterns map onto risk of progression to dementia.

Purpose: Identification of demographic, physical/physiological, lifestyle and genetic factors contributing to the onset of dementia, specifically Alzheimer disease (AD), and implementation of novel methods for early diagnosis are important to alleviate prevalence of dementia globally. The Czech Brain Aging Study (CBAS) is the first large, prospective study to address these issues in Central/Eastern Europe by enrolling non-demented adults aged 55+ years, collecting a variety of personal and biological measures and tracking cognitive function over time., Participants: The CBAS recruitment was initiated in 2011 from memory clinics at Brno and Prague University Hospitals, and by the end of 2018, the study included 1228 participants. Annual follow-ups include collection of socioeconomic, lifestyle and personal history information, neurology, neuropsychology, laboratory, vital sign and brain MRI data. In a subset, biomarker assessment (cerebrospinal fluid (CSF) and amyloid positron emission tomography) and spatial navigation were performed. Participants were 69.7±8.1 years old and had 14.6±3.3 years of education at baseline, and 59% were women. By the end of 2018, 31% finished three and more years of follow-up; 9% converted to dementia. Apolipoprotein E status is available from 95% of the participants. The biological sample bank linked to CBAS database contained CSF, serum and DNA., Findings to Date: Overall, the findings, mainly from cross-sectional analyses, indicate that spatial navigation is a promising marker of early AD and that it can be distinguished from other cognitive functions. Specificity of several standard memory tests for early AD pathology was assessed with implications for clinical practice. The relationship of various lifestyle factors to cognition and brain atrophy was reported., Future Plans: Recruitment is ongoing with secured funding. Longitudinal data analyses are currently being conducted. Proposals for collaboration on specific data from the database or biospecimen, as well as collaborations with similar cohort studies to increase sample size, are welcome. Study details are available online (www.cbas.cz)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Identifying protective factors that promote healthy cognitive aging is of importance due to the growing older adult population. Preventing chronic hyperglycemia may be one such way to preserve cognitive abilities, as high blood glucose levels have been associated with cognitive impairment and decline., Objective: To evaluate the influence of blood glucose levels on cognition among older adults using common neuropsychological tests and a spatial navigation task., Methods: The association between cognitive performance and blood glucose levels was assessed among 117 older adults classified as cognitively healthy, subjective cognitive decline, amnestic mild cognitive impairment, or Alzheimer's disease dementia from the Czech Brain Aging Study. Cognitive abilities were measured by tests of verbal memory, nonverbal memory, working memory, visuospatial skills, and executive function. A test of spatial navigation known as the Hidden Goal Task was also used. Blood glucose levels were measured by glycosylated hemoglobin A1c (HbA1c). Analyses were performed using multiple linear regression controlling for age, gender, education, depressive symptoms, diabetes, and cognitive status., Results: A significant relationship was observed for HbA1c and executive function performance (beta = -2.46, SE = 0.92, p = 0.008). Following moderation analysis, this relationship was significant only among those with cognitive impairment (beta = -4.37, SE = 1.28, p = 0.001, 95% CI [-6.91, -1.83]). Associations between HbA1c and other cognitive domains were not significant (ps > 0.05)., Conclusions: Higher HbA1c was associated with poorer executive function among persons with cognitive impairment, but not with performance on other cognitive domains. Maintaining proper glucoregulation may help preserve executive function performance among cognitively impaired older adults.

Background: Great effort has been put into developing simple and feasible tools capable to detect Alzheimer's disease (AD) in its early clinical stage. Spatial navigation impairment occurs very early in AD and is detectable even in the stage of mild cognitive impairment (MCI)., Objective: The aim was to describe the frequency of self-reported spatial navigation complaints in patients with subjective cognitive decline (SCD), amnestic and non-amnestic MCI (aMCI, naMCI) and AD dementia and to assess whether a simple questionnaire based on these complaints may be used to detect early AD., Method: In total 184 subjects: patients with aMCI (n=61), naMCI (n=27), SCD (n=63), dementia due to AD (n=20) and normal controls (n=13) were recruited. The subjects underwent neuropsychological examination and were administered a questionnaire addressing spatial navigation complaints. Responses to the 15 items questionnaire were scaled into four categories (no, minor, moderate and major complaints)., Results: 55% of patients with aMCI, 64% with naMCI, 68% with SCD and 72% with AD complained about their spatial navigation. 38-61% of these complaints were moderate or major. Only 33% normal controls expressed complaints and none was ranked as moderate or major. The SCD, aMCI and AD dementia patients were more likely to express complaints than normal controls (p's<0.050) after adjusting for age, education, sex, depressive symptoms (OR for SCD=4.00, aMCI=3.90, AD dementia=7.02) or anxiety (OR for SCD=3.59, aMCI=3.64, AD dementia=6.41)., Conclusion: Spatial navigation complaints are a frequent symptom not only in AD, but also in SCD and aMCI and can potentially be detected by a simple and inexpensive questionnaire., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Research shows that lipid levels may be associated with cognitive function, particularly among women. We aimed to examine total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), high-density lipoprotein (HDL), and HDL/LDL ratio in relation to cognitive performance, measured with six well-established cognitive domains and a composite cognitive score (CCS)., Methods: In this cross-sectional study, biomarkers and neuropsychological assessment were available for 141 adults with MMSE scores ≥ 24 (mean age = 69 years, 47% female, mean education = 14.4 years) attending a neuropsychological evaluation. Ordinary least squares regressions were adjusted for age, gender, education, and depressive symptoms in Model 1 and also for apolipoprotein E4 (APOE4) status in Model 2., Results: High-density lipoprotein cholesterol (HDL-C) was associated with better CCS (β = 0.24; p = 0.014). This association was significant among women (β = 0.30; p = 0.026) and not among men (β = 0.20; p = 0.124). HDL-C was also related to attention/working memory (β = 0.24; p = 0.021), again only among women (β = 0.37; p = 0.012) and not men (β = 0.15; p = 0.271). Adjusting for APOE4 yielded significance for high HDL-C and CCS (β = 0.24; p = 0.022)., Conclusions: HDL-C was the main lipoprotein affecting cognitive function, with results somewhat more pronounced among women. Research should investigate the possibility of finding ways to boost HDL-C levels to potentially promote cognitive function.

Objective: The authors conducted a randomized control trial to examine the effect of the Exercise Dance for Seniors (EXDASE) program on lower-body functioning among older individuals from residential care facilities in the Czech Republic., Method: Participants were randomly assigned into an experimental or control group. The experimental group completed a 3-month EXDASE program. Lower-body functioning was assessed using four performance-based measures. A 2 (group) x 2 (test) general linear model for repeated measures was used to explore whether differences in performance could be attributed to the intervention., Results: The authors found Group x Test interactions for the chair stand test, F(1, 50) = 14.37, p < .001, the 2-minute step test, F(1, 50) = 7.33, p = .009, the chair sit-and-reach test, F(1, 50) = 5.28, p = .026, and the timed up-and-go test, F (1, 44) = 6.59, p = .014, indicating that the experimental group outperformed the control group from pretest to posttest., Discussion: A relatively simple dance-based exercise can support lower-body functioning in previously sedentary, frail older adults.