Mobile technologies in the early detection of cognitive decline.

The identification of biological and pathophysiological processes implicated in different forms of dementia is itself dependent on reliable descriptions of cognitive performance and capacities. However, traditional instruments are often unable to detect subtle declines in cognitive functions due to natural variation at the time of testing. Mobile technologies permit the repeated assessment of cognitive functions and may thereby provide more reliable descriptions of early cognitive difficulties that are inaccessible to clinic or hospital-based instruments.

Carotid plaque as a predictor of dementia in older adults: the Three-City Study.

Background: The contribution of carotid atherosclerosis to incident dementia remains unclear. We examined the association between carotid plaques (CP) and common carotid intima media thickness (CCA-IMT) with incident dementia and its subtypes, and their added value for dementia risk prediction.

Methods: At baseline, 6025 dementia-free subjects aged 65-86 years underwent bilateral carotid ultrasonography measures of CP and plaque-free CCA-IMT.

Target risk factors for dementia prevention: a systematic review and Delphi consensus study on the evidence from observational studies.

Objective: Dementia has a multifactorial etiology, but the importance of individual health and lifestyle related risk factors is often uncertain or based on few studies. The goal of this paper is to identify the major modifiable risk factors for dementia as a first step in developing an effective preventive strategy and promoting healthy late life cognitive functioning.

Methods: A mixed-method approach combined findings from a systematic literature review and a Delphi consensus study.

Change in leisure and social activities and risk of dementia in elderly cohort.

Objective: To investigate the association of the change in practice of leisure and social activities with dementia risk taking into account the evolution of cognitive performances.

Design, Setting, And Participants: From the PAQUID prospective cohort re-examined every 2 years until the 20-year follow-up since 1988, 1461 subjects were seen at 10th year of follow-up. Engagement in 10 leisure and social activities was collected at baseline and at the 10-year follow-up visit for 805 subjects.

Lifetime exposure to ambient ultraviolet radiation and the risk for cataract extraction and age-related macular degeneration: the Alienor Study.

Purpose: While exposure to ultraviolet radiation (UVR) is a recognized risk factor for cataract, its association is more controversial with age-related macular degeneration (AMD). We report the associations of lifetime exposure to ambient UVR with cataract extraction and AMD.

Methods: The Alienor Study is a population-based study of 963 residents of Bordeaux (France), aged 73 years or more.

Quantifying and comparing dynamic predictive accuracy of joint models for longitudinal marker and time-to-event in presence of censoring and competing risks.

Thanks to the growing interest in personalized medicine, joint modeling of longitudinal marker and time-to-event data has recently started to be used to derive dynamic individual risk predictions. Individual predictions are called dynamic because they are updated when information on the subject's health profile grows with time. We focus in this work on statistical methods for quantifying and comparing dynamic predictive accuracy of this kind of prognostic models, accounting for right censoring and possibly competing events.

Association between frailty and carotid central structure changes: the Three-City Study.

Objectives: To demonstrate the association between carotid central structure changes and frailty.

Design: Cross-sectional study.

Setting: The Three-City Study, a French prospective cohort designed to evaluate the risk of cognitive decline attributable to vascular risk factors.

Normalized Mini-Mental State Examination for assessing cognitive change in population-based brain aging studies.

Background: The Mini-Mental State Examination (MMSE) is widely used in population-based longitudinal studies to quantify cognitive change. However, its poor metrological properties, mainly ceiling/floor effects and varying sensitivity to change, have largely restricted its usefulness. We propose a normalizing transformation that corrects these properties, and makes possible the use of standard statistical methods to analyze change in MMSE scores.

[The DMS 48: norms and diagnostic proprieties for Alzheimer's disease in elderly population from the AMI cohort study].

Unlabelled: The DMS 48 is a visual recognition memory test designed to detect memory changes in early Alzheimer's disease (AD). The aim of this study was to produce normative scores for this test and to assess its psychometric properties in the detection of AD by comparison with a widely used test of verbal episodic memory: the story recall task of the Wechsler memory scale. Methods.

Hierarchical structure of the activities of daily living scale in dementia.

Objectives: To describe the sequence of basic activities of daily living (ADL) loss to determine whether there is a hierarchical structure of ADL in dementia in two epidemiological prospective studies: the Paquid study and the Three City Study (3C).

Design: Two prospective population-based cohort studies: Paquid (over 22 years of follow-up) and 3C (over 10 years of follow-up).

Setting: Paquid Study, Gironde, Dordogne, France; The Three Cities Study, Bordeaux, Montpellier, Dijon, France.

Prognostic score for predicting risk of dementia over 10 years while accounting for competing risk of death.

Early detection of subjects at high risk of developing dementia is essential. By dealing with censoring and competing risk of death, we developed a score for predicting 10-year dementia risk by combining cognitive tests, and we assessed whether inclusion of cognitive change over the previous year increased its discrimination. Data came from the French prospective cohort study Personnes Agées QUID (PAQUID) and included 3,777 subjects aged 65 years or older (1988-1998).

Is dependent personality disorder associated with mild cognitive impairment and dementia in Central Africa? A result from the EPIDEMCA programme.

Background: To date, no studies have examined the relationship between cognitive disorders and personality disorders. Our aim was to investigate the association between dependent personality disorder (DPD) and cognitive disorders in Central Africa.

Methods: Between 2011 and 2012, a cross-sectional multicenter population-based study was carried out in rural and urban areas of the Central African Republic (CAR) and the Republic of Congo (ROC).

The use of biomarkers for the etiologic diagnosis of MCI in Europe: an EADC survey.

We investigated the use of Alzheimer's disease (AD) biomarkers in European Alzheimer's Disease Consortium centers and assessed their perceived usefulness for the etiologic diagnosis of mild cognitive impairment (MCI). We surveyed availability, frequency of use, and confidence in diagnostic usefulness of markers of brain amyloidosis (amyloid positron emission tomography [PET], cerebrospinal fluid [CSF] Aβ42) and neurodegeneration (medial temporal atrophy [MTA] on MR, fluorodeoxyglucose positron emission tomography [FDG-PET], CSF tau). The most frequently used biomarker is visually rated MTA (75% of the 37 responders reported using it "always/frequently") followed by CSF markers (22%), FDG-PET (16%), and amyloid-PET (3%).

Survival and early recourse to care for dementia: A population based study.

Background: A large proportion of dementia cases are still undiagnosed. Although early dementia care has been hypothesized to benefit both patients and families, evidence-based benefits are lacking. Thus, investigating the benefits for newly demented persons according to their recourse to care in the "real life" appears critical.

Epidemiology of dementia in Central Africa (EPIDEMCA): protocol for a multicentre population-based study in rural and urban areas of the Central African Republic and the Republic of Congo.

Background: The worldwide population is ageing and the proportion of elderly aged 60 and over is expected to dramatically rise in Low and Middle Income Countries (LMIC). The epidemic of dementia will not spare those countries, where the largest increases in numbers of people affected are estimated. Besides, dementia is still understudied in sub-Saharan Africa (SSA) compared to other regions.

MAPT STUDY: A MULTIDOMAIN APPROACH FOR PREVENTING ALZHEIMER'S DISEASE: DESIGN AND BASELINE DATA.

Objective: The Multidomain Alzheimer Preventive Trial (MAPT study) was designed to assess the efficacy of isolated supplementation with omega-3 fatty acid, an isolated multidomain intervention (consisting of nutritional counseling, physical exercise, cognitive stimulation) or a combination of the two interventions on the change of cognitive functions in frail subjects aged 70 years and older for a period of 3 years. Ancillary neuroimaging studies were additionally implemented to evaluate the impact of interventions on cerebral metabolism (FDG PET scans) and atrophy rate (MRIs), as well as brain amyloïd deposit (AV45 PET scans).

Design Patients: 1680 subjects (mean age: 75.

Receiver operating characteristic curve estimation for time to event with semicompeting risks and interval censoring.

Semicompeting risks and interval censoring are frequent in medical studies, for instance when a disease may be diagnosed only at times of visit and disease onset is in competition with death. To evaluate the ability of markers to predict disease onset in this context, estimators of discrimination measures must account for these two issues. In recent years, methods for estimating the time-dependent receiver operating characteristic curve and the associated area under the ROC curve have been extended to account for right censored data and competing risks.

Cognitive decline after entering a nursing home: a 22-year follow-up study of institutionalized and noninstitutionalized elderly people.

Objective: The objective of this study is to compare cognitive decline of elderly people after entering an institution with that of elders living in the community with similar clinical conditions.

Design: The Personnes Agées QUID (PAQUID) cohort is a prospective population-based study which included, at baseline, 3777 community-dwelling people aged 65 years and older. Participants were followed-up for 22 years.

Estimating long-term multivariate progression from short-term data.

Motivation: Diseases that progress slowly are often studied by observing cohorts at different stages of disease for short periods of time. The Alzheimer's Disease Neuroimaging Initiative (ADNI) follows elders with various degrees of cognitive impairment, from normal to impaired. The study includes a rich panel of novel cognitive tests, biomarkers, and brain images collected every 6 months for as long as 6 years.

Elevated high-density lipoprotein cholesterol and age-related macular degeneration: the Alienor study.

Background: Lipid metabolism and particularly high-density lipoprotein (HDL) may be involved in the pathogenic mechanism of age-related macular degeneration (AMD). However, conflicting results have been reported in the associations of AMD with plasma HDL and other lipids, which may be confounded by the recently reported associations of AMD with HDL-related genes. We explored the association of AMD with plasma lipid levels and lipid-lowering medication use, taking into account most of HDL-related genes associated with AMD.

Compensatory mechanisms in higher-educated subjects with Alzheimer's disease: a study of 20 years of cognitive decline.

A better knowledge of long-term trajectories of cognitive decline is a central feature of the study of the process leading to Alzheimer's dementia. Several factors may mitigate such decline, among which is education, a major risk factor for Alzheimer's disease. The aim of our work was to compare the pattern and duration of clinical trajectories before Alzheimer's dementia in individuals with low and high education within the PAQUID cohort involving 20 years of follow-up.

Cognitive lifestyle jointly predicts longitudinal cognitive decline and mortality risk.

Cognitive lifestyle measures such as education, occupation, and social engagement are commonly associated with late-life cognitive ability although their associations with cognitive decline tend to be mixed. However, longitudinal analyses of cognition rarely account for death and dropout, measurement error of the cognitive phenotype, and differing trajectories for different population sub-groups. This paper applies a joint latent class mixed model (and a multi-state model in a sensitivity analysis) that accounts for these issues to a large (n = 3,653), population-based cohort, Paquid, to model the relationship between cognitive lifestyle and cognitive decline.

Restriction in instrumental activities of daily living in older persons: association with preferences for routines and psychological vulnerability.

Disabilities in the Instrumental Activities of Daily Living (IADL) are frequently observed in older adults. A restriction in the daily life activities in the elderly may be related to a process of routinization induced by homogenization of activities, in addition to its association with emotional states. The relationship between level of functional disability for IADLs and preferences for routines was explored in 207 non-demented French participants (Mage = 84.

A genome-wide association meta-analysis of plasma Aβ peptides concentrations in the elderly.

Amyloid beta (Aβ) peptides are the major components of senile plaques, one of the main pathological hallmarks of Alzheimer disease (AD). However, Aβ peptides' functions are not fully understood and seem to be highly pleiotropic. We hypothesized that plasma Aβ peptides concentrations could be a suitable endophenotype for a genome-wide association study (GWAS) designed to (i) identify novel genetic factors involved in amyloid precursor protein metabolism and (ii) highlight relevant Aβ-related physiological and pathophysiological processes.