Alzheimer's Disease is a complex, multifactorial, and comorbid condition. The asymptomatic behavior in the early stages makes the identification of the disease onset particularly challenging. Mild ...cognitive impairment (MCI) is an intermediary stage between the expected decline of normal aging and the pathological decline associated with dementia. The identification of risk factors for MCI is thus sorely needed. Self-reported personal information such as age, education, income level, sleep, diet, physical exercise, etc. is called to play a key role not only in the early identification of MCI but also in the design of personalized interventions and the promotion of patients empowerment. In this study, we leverage a large longitudinal study on healthy aging in Spain, to identify the most important self-reported features for future conversion to MCI. Using machine learning (random forest) and permutation-based methods we select the set of most important self-reported variables for MCI conversion which includes among others, subjective cognitive decline, educational level, working experience, social life, and diet. Subjective cognitive decline stands as the most important feature for future conversion to MCI across different feature selection techniques.
Cognitive neuropsychology seeks a potential alignment between structural and functional brain features to explain physiological or pathological processes, such as Alzheimer’s disease (AD). Several ...structural and functional brain changes occurring during the disease, including cognitive impairment, are found at the end of the patient’s life, but we need to know more about what happens before its onset. In order to do that, we need earlier biomarkers at preclinical stages, defined by those biomarkers, to prevent the cognitive impairment. In this minireview, we have tried to describe the structural and functional changes found at different stages during AD, focusing on those features taking place before clinical diagnosis.
Introduction
The theoretical framework of the Alzheimer's disease continuum considers transition between stages in a unidirectional manner. Here we examine the rate of reversion from mild cognitive ...impairment (MCI) to normal cognition (NC) and explore a set of potential variables associated with this phenomenon.
Methods
A total of 985 Spanish community‐dwelling individuals aged 70 years and over at baseline were monitored for 5 years. During this time, 173 MCI and 36 dementia cases were identified. Multi‐state Markov models were performed to characterize transitions between states through the dementia continuum.
Results
The rate of reversion from MCI to NC was 11%. There were significant non‐modifiable (age, socioeconomic status, or apolipoprotein E) and modifiable factors (cognitive training or absence of affective symptoms) associated with reversion.
Discussion
Overall, our results highlight that the likelihood of progression from MCI to dementia is very similar to that of reversion from MCI to NC.
Alzheimer's disease (AD) is a silent disorder that needs the earliest possible intervention in order to reduce its high economic and social impact. It has been recently suggested that subjective ...cognitive decline (SCD) appears at preclinical stages many years before the onset of AD. Therefore, SCD could become an ideal target for early therapeutic intervention.
The goal of this study was to evaluate the clinical significance of SCD on the conversion from a cognitively healthy stage to a mild cognitive impairment (MCI) in one-year follow-up.
A total of 608 cognitively intact individuals from the Vallecas Project's cohort, a community-based prospective study to identify early markers of AD, were enrolled in this study. Participants were classified in three groups: i) No Complaints (NCg), ii) Subjects with complaints in one or more cognitive domains (SCDg), and iii) Subjects who, besides complaints, fulfilled the features of SCD Plus proposed by the International Working Group of SCD (SCD-Pg).
Individuals were followed up for a mean of 13.1 months (range 10.7-22.4). During this time, 41 volunteers developed MCI (6.7% of total sample). The conversion rate for SCD-Pg (18.9%) was significantly higher than SCDg (5.6%) and NCg (4.9%).
Specific features associated with SCD may help to identify individuals at high risk of fast conversion to MCI. These results highlight the importance of a close follow-up of subjects with SCD-P and include them in early intervention programs because of their increased risk for the development of MCI.
...the concerns on SCD in clinical samples may be higher than in community-dwelling individuals. ...it would be suitable to rely on tools with adequate psychometric properties for the reference ...population. ...another critical point is to determine the reference period of time in which we want to examine the SCD. In psychometric terms, when we are measuring subjective variables like SCD we are actually obtaining two different types of information: (i) the construct of interest (i.e., SCD in our case); and (ii) errors of measurement which comprise the error variance and include information regarding other irrelevant constructs (e.g., depressive symptoms associated with a particular complaint, personality traits, etc.) as well as short-term fluctuations due to shifts in self-perception itself. ...when repeated subjective measurements are collected from an individual the scores on two different occasions may be quite different (Nesselroade and Salthouse, 2004). ...neuropsychiatric variables should be collected as well because of their mediator role between SCD and cognitive decline.
In recent years, many efforts are being made to produce tef-based food for its nutritive and health-promoting advantages. Tef grain is always whole milled because of its tiny grain size and whole ...flours contain bran (pericarp, aleurone, and germ) where major non-starch lipids could be deposited along with the lipid-degrading enzymes: lipase and lipoxygenase. As lipoxygenase shows little activity in low moisture, the inactivation of lipase is the common objective for most heat treatments to extend the shelf life of flours. In this study, tef flour lipase inactivation kinetics via hydrothermal treatments assisted using microwaves (MW) were studied. The effects of tef flour moisture level (12%, 15%, 20%, and 25%) and MW treatment time (1, 2, 4, 6, and 8 min) on flour lipase activity (LA) and free fatty acid (FFA) content were evaluated. The effects of MW treatment on flour pasting characteristics and the rheological properties of gels prepared from the treated flours were also explored. The inactivation process followed a first-order kinetic response and the apparent rate constant of thermal inactivation increased exponentially with the moisture content of the flour (
) according to the equation 0.048·exp (0.073·
) (R
= 0.97). The LA of the flours decreased up to 90% under the studied conditions. MW treatment also significantly reduced (up to 20%) the FFA level in the flours. The rheological study confirmed the presence of significant modifications induced by the treatment, as a lateral effect of the flour stabilization process.
The progressive aging of the population represents a challenge for society. In particular, a strong increase in the number of people over 90 is expected in the next two decades. As this phenomenon ...will lead to an increase in illness and age-related dependency, the study of long-lived people represents an opportunity to explore which lifestyle factors are associated with healthy aging and which with the emergence of age-related diseases, especially Alzheimer's type dementia. The project "Factors associated with healthy and pathologically aging in a sample of elderly people over 90 in the city of Madrid" (MADRID+90) brings together a multidisciplinary research team in neurodegenerative diseases that includes experts in epidemiology, neurology, neuropsychology, neuroimaging and computational neuroscience. In the first phase of the project, a stratified random sampling was carried out according to the census of the city of Madrid followed by a survey conducted on 191 people aged 90 and over. This survey gathered information on demographics, clinical data, lifestyles and cognitive status. Here, the main results of that survey are showed. The second phase of the project aims to characterize individual trajectories in the course of either healthy and pathological aging, from a group of 50 subjects over 90 who will undergo a comprehensive clinical examination comprised of neurological and cognitive testing, MRI and EEG. The ultimate goal of the project is to characterize the biophysical and clinical profiles of a population that tends to receive little attention in the literature. A better understanding of the rapidly increasing group of nonagenarians will also help to design new policies that minimize the impact and future social and economic consequences of rapidly aging societies.
Objectives: There is strong evidence about the association between low socioeconomic status (SES) and higher risk of dementia. However, it has not been conveniently addressed so far the role of SES ...on the incidence of mild cognitive impairment (MCI). This study examines the impact of individual and neighbourhood dimensions of SES, as well as their interaction, on the risk of developing MCI in a sample of older adults.
Method: Data from the Vallecas Project cohort, an ongoing community-based longitudinal study for early detection of cognitive impairment and dementia, were used to build two indices of SES namely individual and neighbourhood, as well as a global SES as a combination of both, and to investigate their effects on MCI conversion by means of a multivariate-adjusted Cox proportional hazard model.
Results: A total of 1180 participants aged 70 years and older were enrolled in this study. Of these, 199 cases of MCI (16.9%) were diagnosed at any point of the follow-up. The individual and neighbourhood dimensions of SES played different roles in the dynamics of the MCI occurrence through aging. Most importantly, the risk of developing MCI was almost double for lower SES quartiles when compared to the highest one.
Conclusion: The incidence of MCI in older adults was related to both individual characteristics and socioeconomic context. Public health strategies should be holistic and focus not only on promoting the classical individual preventive measures, but also on reducing social inequalities to foster healthy aging and reduce dementia burden.
...prior to the onset of dementia, it appears a prodromal stage called mild cognitive impairment (MCI) which is characterized by the presence of cognitive deficits, but not severe enough to ...significantly affect everyday activities (Petersen et al., 1999). ...chronic stress have been reported to accelerate AD pathogenesis in mouse models for AD, including extracellular beta-amyloid plaque deposition and intracellular tau hyperphosphorylation (Carroll et al., 2011; Sotiropoulos et al., 2011; Justice et al., 2015). Other animal studies have provided direct evidencet of the deleterous effects of glucocorticoids on hippocampal morphology. ...sustained exposure to elevated corticosteroid levels has been found to alter dendritic morphology and reduce hippocampal volume in different hippocampal subfields (Woolley et al., 1990; Sousa et al., 1998, 2000). In humans, although the evidence in older adults is somehow inconclusive (Cox et al., 2017), a similar pattern of hippocampal atrophy largely consistent with animal models has been described. ...older adults with persistently high cortisol levels over a 5-year period, or even with higher levels of perceived chronic stress, show a preferential volume loss in CA4/dentate gyrus and CA2/CA3 subfields (Lupien et al., 1998, 2007; Zimmerman et al., 2016).
Ultrasonic (USC) treatments have been applied to starches, flours and grains to modify their physicochemical properties and improve their industrial applicability. The extent of the modification ...caused by USC treatment depends on the treatment conditions and the natural characteristics of the treated matter. Cavitation leads to structural damage and fragmentation and partial depolymerization of starch components. The amorphous regions are more susceptible to being disrupted by ultrasonication, while the crystalline regions require extended USC exposure to be affected. The increased surface area in USC-treated samples has a higher interaction with water, resulting in modification of the swelling power, solubility, apparent viscosity, pasting properties and gel rheological and textural properties. Starch digestibility has been reported to be modified by ultrasonication to different extents depending on the power applied. The most important treatment variables leading to more pronounced modifications in USC treatments are the botanical origin of the treated matter, USC power, time, concentration and temperature. The interaction between these factors also has a significant impact on the damage caused by the treatment. The molecular rearrangement and destruction of starch structures occur simultaneously during the USC treatment and the final properties of the modified matrix will depend on the array of treatment parameters. This review summarizes the known effects of ultrasonic treatments in modifying starches, flours and grains.
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