Early Symptoms Of Dementia Research Articles

Pilot Study of Reticular Activating System (RAS) in Mild Dementia

AbstractBackgroundClinically, the common early symptoms of dementia include memory problems, reduced concentration, behaviour changes, apathy and withdrawal, loss of ability to do everyday tasks. These cognitive functions are mediated by the reticular activating system (RAS) that is a collection of interconnected brain nuclei that regulates wakefulness, alertness and modulate behaviors. The RAS degenerates early during Alzheimer’s disease progression in association with abnormal tau build‐up.MethodThis study aimed to explore the relationship between the RAS functioning and older people with mild grade dementia. The Kendrick Object Learning Test (KOLT) is a test of recall of everyday objects after viewing for a brief period, an immediate recall of briefly perceived visual data. The Kendrick Digit Copying Test (KDCT) is a test of speed in processing and recording information. These tests suggested cortical excitation mediated by both the RAS and the hypothalamic limbic network which deteriorate in older people with mild grade dementia.ResultIn this pilot study, 25 demented patients with mild grade dementia and 20 participants with known depression were recruited. They are matched in age (mean age 72 with sd 4.89) and shared similar demographic background. The participants were tested with the Kendrick Object Learning Test (KOLT) and the Kendrick Digit Copying Test (KDCT). To observe the short term longitudinal change of their RAS functioning, these tests were administered again 4 weeks following baseline. With regular day activity treatment, the depressive group showed improvement in KOLT (p < 0.1), but not on KDCT (p = .82). However, in the dementia group, there were no significant difference noted in both KOLT and KDCT (p < 0.5).ConclusionThe present findings echo some findings of RAS does not function properly as in the older people with dementia. The reticular system is not compromised in group of depressive participants, there would be improvement in object learning, but no significant difference on speed in processing and recording information as measured by speed‐performance tests (KDCT). Proper and targeted rehabilitation trainings and care giving techniques could be arranged in meeting the specific patients’ needs.

Evaluation of Brain Perfusion with Radionuclide Imaging in Dementia Patients

Objective: This study aims to evaluate the perfusion in the affected brain lobes with radionuclide imaging in patients with dementia and to contribute to the literature by determining the relationship between the degree of dementia. Methods: In this retrospective study, 44 adult patients were included. The mean age of the patients was 73 (57-87). Twenty-three (52.3%) of these were female. All patients underwent mini-mental state test, neurological examinations and radionuclide brain perfusion imaging. The areas of interest of the frontal, parietal, temporal, and occipital lobes and the cerebellum were drawn, respectively, and the cerebellum ratios of the relevant lobes were compared. In this way, brain perfusion index values of lobes were obtained. Results: Brain perfusion in group 1 was higher than in other groups. Groups were also compared in pairs. There was no significant difference in perfusion values in the occipital lobe. There was a significant difference in perfusion between groups 1 and 2 in lobes other than the occipital lobe. This was also the case for Groups 1 and 3. When group 2 with early dementia symptoms, and group 3 with moderate dementia were compared, there was a significant difference between the perfusion values of only the right and left frontal lobes. Conclusion: Early diagnosis is very important in progressive dementia. Clinical tests are successfully applied to categorize patients. Evaluation of brain perfusion and metabolism with functional radionuclide imaging is significant in guiding the treatment and evaluating the success of the treatment.

Recognition and assessment of dementia in a primary care setting

Receiving a timely and accurate diagnosis of dementia is essential to enable people to access vital treatment and support, reduce the risk of premature deterioration, and empower families to live well and plan. However, there are several challenges associated with obtaining a timely diagnosis, which have been exacerbated by the coronavirus disease 2019 (COVID-19) pandemic. This article outlines some of these challenges, describes the similarities between early symptoms of dementia and other health conditions and details the dementia diagnosis pathway in primary care. The authors use a case study to demonstrate this pathway.

Smart Home Technologies to Facilitate Ageing-in-Place: Professionals Perception

An ageing population is a global phenomenon. Like other developed economies, Hong Kong Special Administrative Region (HKSAR), China, also faces a severe ageing problem. One initiative to enhance the safe living and well-being of the growing elderly population is to assist them by building ageing-friendly living environments with the application of smart home technologies (SHTs). Therefore, this study focused on investigating the perception of professionals on the use of SHTs to improve and enhance the “ageing-in-place” (AIP) of elderly residents in HKSAR, China. A questionnaire survey was employed to obtain the perception of professionals with requisite knowledge of the older people facility needs regarding SHTs in achieving AIP for the elderly. The data retrieved were analysed with different statistical analyses. Based on the results of the analyses, all the professionals had similar perceptions of the use of SHTs for the safety and well-being of the elderly, except for the incongruence observed between the government employees, contractors and academic regarding how SHTs may not help to better monitor elderly daily activities. The possible reasons for the inconsistent opinions of the academics with other groups were linked to the knowledge of human behaviours and early dementia symptoms in gerontology. The findings will help care receivers, healthcare professionals, social workers, policymakers, smart home designers and developers to improve and enhance AIP in elderly residences in HKSAR, China.

Sleep disorders and incident dementia: a nationwide observational cohort study

AbstractBackgroundIn recent years, significant research efforts have focused on identifying modifiable risk factors to be leveraged for dementia prevention. Sleep is required for memory consolidation and normal brain functioning, and various mechanisms are proposed between poor sleep quality and cognitive impairment. Several studies have examined the role of sleep disturbances as a risk factor for dementia; however, most of these studies have involved smaller cohorts and short time intervals, and often rely on retrospective surveys and self‐reported exposure data. Our aim was to examine the association between sleep disorders and late‐onset dementia in an entire population.MethodIn a nationwide cohort with a 40‐year follow up, we linked nationwide population data with information on hospital‐based sleep disorder diagnoses and late‐onset dementia from the extensive Danish health registers. Incidence rate ratios (IRR) were calculated using Poisson regression analysis. Analyses were adjusted for age, sex, calendar year, education, and somatic and psychiatric comorbidities.ResultThe cohort consisted of 1,491,276 people. Those with any hospital‐diagnosed sleep disorder had a 17% higher risk of dementia (IRR 1.17, 95% CI 1.11‐1.24) compared to people with no sleep disorder diagnosis. The highest risk was found for men with ‘other specific disorders’ (e.g. insomnia, hypersomnia, non‐organic sleep disorders) with an IRR of 2.00 (95% CI 1.71‐2.32). The risk of dementia was significantly increased 0 to 5 years after sleep disorder diagnosis (IRR 1.35, 95% CI 1.25‐1.47), while the association after 5 years or more was non‐significant (1.05, 95% CI 0.97‐1.13).ConclusionOur findings indicate an increased short‐term risk of dementia following a hospital‐based sleep disorder diagnosis, while we found weaker evidence of a long‐term risk. While this may indicate that sleep disorders could be early symptoms of dementia as well as a risk factor, further research is needed to evaluate sleep disorders as potential early symptoms of dementia, risk factors for dementia, or both, and characterize how this may change at different points along the dementia course. Increased knowledge of the role of sleep disorders in dementia could help inform efforts towards diagnosing dementia in the early stages of the disease or even in dementia prevention.

Preeclampsia, gestational hypertension and incident dementia: A systematic review and meta-analysis of published evidence.

Novel data support a possible correlation between preeclampsia and congenital dysfunction. A systematic review of the literature and a meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and meta-Analyses (PRISMA) guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. To investigate the association between the risk of future of dementia (vascular dementia, AD and dementia of any type) in women with a history of preeclampsia, based on current literature. Overall, three studies and 2.309.946 women were included in the present meta-analysis. There was no statistically significant association between history of preeclampsia or pregnancy hypertension disease and any type of dementia (p=0.14 and p=0.29, respectively). In contrast, there was a statistically significant difference between history of preeclampsia and vascular dementia (HR: 2.60; 95%CI: 2.03-3.33; p<0.001). Furthermore, history of preeclampsia does not increase the risk for Alzheimer disease (Fixed Effects pooled-HR: 1.17; 95%CI: 0.98-1.40; p=0.08). Similarly, women with hypertensive disorder of pregnancy (HDP) had no statistically significant increased risk for later onset of any dementia (Fixed Effects pooled-HR: 1.08; 95%CI: 0.93-1.25; p=0.29). History of preeclampsia increases the risk of vascular dementia. These patients are expected to benefit from screening for early symptoms of dementia, allowing early diagnosis and treatment. However, due to several limitations, further studies with large cohorts are required to elucidate the association between preeclampsia and dementia.

Exploring electrophysiological markers of auditory predictive processes and pathological ageing in adults with Down's syndrome.

Down's syndrome is associated with pathological ageing and a propensity for early-onset Alzheimer's disease. The early symptoms of dementia in people with Down's syndrome may reflect frontal lobe vulnerability to amyloid deposition. Auditory predictive processes rely on the bilateral auditory cortices with the recruitment of frontal cortices and appear to be impaired in pathologies characterized by compromised frontal lobe. Hence, auditory predictive processes were investigated to assess Down's syndrome pathology and its relationship with pathological ageing. An auditory electroencephalography (EEG) global-local paradigm was presented to the participants, in which oddball stimuli could either violate local or higher level global rules. We characterised predictive processes in individuals with Down's syndrome and their relationship with pathological ageing, with a focus on the EEG event-related potential called Mismatch Negativity (MMN) and the P300. In Down's syndrome, we also evaluated the EEG components as predictor of cognitive decline 1 year later. We found that predictive processes of detection of auditory violations are overall preserved in Down's syndrome but also that the amplitude of the MMN to local deviancies decreases with age. However, the 1-year follow-up of Down's syndrome found that none of the ERPs measures predicted subsequent cognitive decline. The present study provides a novel characterization of electrophysiological markers of local and global predictive processes in Down's syndrome.

A Study to Evaluate the Effectiveness of Structured Cognitive Stimulation on Cognitive Functioning Among Women with Early Symptoms of Dementia in Selected Areas of Panipat, Haryana

Background of the study: The stressful life of women is gaining more attention and has come into limelight as a prominent cause of dementia. Dementia is a concern for many women. The women in menopausal transition also seem to be most fearful of developing breast cancer, closely followed by Alzheimer’s dementia. Dementia is one of the leading problems faced by the people worldwide now a days and a matter of worry too.Objective of the Study: To evaluate the effectiveness of structured cognitive stimulation on cognitive functioning among women.Research Methodology: True experimental research design was used in this study; sampling size was 60 mothers. Sampling technique used was simple random sampling method. Data were collected in Babarpur and Dadlana Villages in Panipat District. Haryana. Mini Mental Status Examination were used for data collection. Structured Cognitive Stimulation Program were given for 14 days to the mothers in experimental group. For the mothers in control group no special programs were administered. Data collected were analysed through descriptive and inferential statistics.Results: In experimental group the post-test mean and standard deviation dementia score was 24.47 + 2.389. the control group post-test mean and standard deviation dementia score was 18.00 + 3.129. the mean difference value was 6.47 Paired ‘t’ test score was 8.997 for the degree of freedom 58. The ‘P’ value was 0.000, it was statistically significant at the level of significance &lt; than 0.05.Conclusion: This research demonstrated the cognitive function score on cognitive functioning. However, the subjects with moderately cognitive score were positively benefitted and shifted towards questionably significant level of cognition. This provides a set of baseline data that can be cited for further studies. The Structured Cognitive Stimulation could be incorporated into pre-services or in-service education program in order to evaluate its effectiveness in different populations and settings.

The auditory mismatch negativity reflects accelerated aging in adults with Down’s syndrome

AbstractBackgroundAlzheimer’s disease (AD) affects nearly the entirety of the Down’s Syndrome population (DS) with a prevalence of 75% by the time they reach their 60s. The early symptoms of dementia in DS may reflect frontal lobe vulnerability to amyloid deposition. The Mismatch Negativity (MMN) is a frontocentral event‐related potential (ERP) component elicited by auditory violations. Predictive coding postulates that the brain creates neural predictions about future events by compiling statistical regularities from incoming stimuli. Within the MMN network, the MMN results from the failure of higher frontotemporal nodes to predict the incoming sensory input, which results in changes of coupling between the sensory and the frontotemporal cortices. In the typically developing (TD) population, the MMN response has been found to decrease with age. With a cross‐sectional and longitudinal study, we assessed whether the MMN reflects premature neurological aging in DS and whether it predicts cognitive decline one year later.MethodThe MMN ERP and the MMN Global‐Field Power (GFP) were elicited with an auditory global‐local task and recorded with high‐density EEG in 36 DS adults and in 39 age‐matched TD controls. Cognitive impairment was measured in DS with the neuropsychological battery CAMCOG‐DS. One year later, 34 adults with DS underwent a follow‐up administration of the CAMCOG‐DS. Linear models tested whether the MMN predicted age in the two groups. Linear and curvilinear models tested whether the MMN obtained at the first time‐point was predictive of cognitive decline one year later as measured by changes in CAMCOG‐DS scores.ResultIn the cross sectional phase, an interaction between the MMN amplitude, both expressed in ERP and GFP, and group was found. In particular, MMN amplitude predicted age in DS but not in TD. On the other hand, neither amplitude nor latency of the MMN predicted cognitive decline one year later.ConclusionOur study shows that in our cohort the MMN amplitude reflects accelerated aging in DS but not in TD, suggesting that MMN amplitude may be a sensitive marker of early onset AD in the DS population. On the other hand, neither MMN amplitude or latency predicts cognitive decline one year later.

“We’re Walking Around Blindfolded”: Diverse caregiver reflections on dementia diagnosis and care

AbstractBackgroundPrevalence of dementia is highest in African Americans and Hispanics. Yet, many minorities experience missed or delayed dementia diagnoses and disparities in quality of dementia care. The objective of this study was to understand racial and ethnic minority experiences of dementia diagnosis and develop recommendations for clinicians and health systems to improve diagnosis and early care for diverse populations from the caregiver perspective.MethodMinority dementia caregivers in the Baltimore, Maryland region were recruited from specialty clinics, prior studies, and the Alzheimer’s Association to participate in semi‐structured, in‐depth, qualitative interviews. Interviews topics included early dementia symptoms, diagnosis experiences, healthcare system interactions, and recommendations for clinicians. Interviews were coded and analyzed by three investigators using qualitative content analysis methods.ResultEighteen family caregivers (11 African American, 4 Asian and 3 Hispanic), mostly adult children (n=15) of the person with dementia, participated. Four themes emerged around recommendations for clinicians and health systems throughout the diagnosis process. 1) Involve family: Recommendations pertaining to family involvement included listening to family concerns, sharing patient information including diagnosis, recommending family counseling or meetings, and understanding family and culture specific care plans. 2) Knowledge is power: Information was felt to be essential. Caregivers desired clear or written diagnosis, guidance on what to expect (roadmap), and concrete resources. 3) Provide proactive care: Caregivers likened the need for cognitive screening to cancer screening. They felt clinicians should proactively detect early signs of dementia, educate caregivers on potential challenges (safety, finances), and offer support to both patient and caregivers. 4) Mind your (bedside) manners: Caregivers shared both positive and off‐putting interactions. They appreciated clinicians who were straightforward, demonstrated compassion rather than nihilism or negativity, and were readily available for questions.ConclusionMinority dementia caregivers shared recommendations for clinicians related to four themes, which included involving family, offering knowledge and information, providing proactive care, and being mindful of bedside manner and language in dementia detection, diagnosis, and early care processes. Caregiver perspectives and recommendations should be incorporated into clinical practice and dementia care interventions for diverse aging populations.

Community-Based Best Practices for Early Identification and Referrals for Dementia

Context: The purpose of this article is to describe the typical aging process and compare this to mild cognitive impairment and early symptoms of dementia, specifically cognitive-communicative and swallowing deficits, to help professionals better identify dementia in the care of community-based adults. Objective: To evaluate the role and importance of the speech-language pathologist in early identification and management of dementia. Suggested interprofessional considerations for best practice for early identification, management, and referral are also addressed. Conclusion: Speech-language pathologists are critical for assessing and treating those with early stages of dementia and mild cognitive impairment. It is critical for medical professionals to recognize the speech pathologist's role in treating those with cognitive impairments and swallowing disorders.

Association of cerebral microbleeds with cerebrospinal fluid Alzheimer-biomarkers and clinical symptoms in early dementia with Lewy bodies.

To determine the prevalence, localization and associations of cerebral microbleeds (CMB) in dementia with Lewy bodies (DLB) with its core clinical symptoms and cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD). We hypothesize DLB patients with CMB have increased amyloid burden compared to those without CMB, which could also translate into clinical differences. Retrospective cross-sectional analysis from the AlphaLewyMA study (https://clinicaltrials.gov/ct2/show/NCT01876459). Patients underwent a standardized protocol of brain MRI including 3D T1, 3D FLAIR and T2* sequences, and CSF analysis of AD biomarkers. CMB and white matter hyperintensities (WMHs) were visually assessed in prodromal and mild demented (DLB, N=91) and AD (AD, N=67) patients. CMB prevalence did not differ among DLB and AD (24.2% vs. 37.3%; p=0.081). CMB were mainly distributed in lobar topographies in both DLB (74%) and AD (89%). CMB in DLB was not associated with global cognitive performance, executive functioning, speed of information processing, or AD CSF biomarkers. Similarly, there was no difference regarding specific clinical symptoms: fluctuations, psychotic phenomena, sleep behavior disorder and Parkinsonism between DLB patients with and without CMB. AD patients with CMB had increased burden of WMH compared to those without (2.1±0.86 vs. 1.4±0.89; p=0.005), according to Fazekas scale, whereas no significant difference was observed in DLB patients (1.68±0.95 vs. 1.42±0.91; p=0.25). CMB were equally prevalent with similar topographic distribution in both DLB and AD patients. CMB was not associated with CSF AD biomarkers or core clinical symptoms in DLB.

Being in the Past and Perform the Future in a Virtual World: VR Applications to Assess and Enhance Episodic and Prospective Memory in Normal and Pathological Aging.

The process of aging commonly features a gradual deterioration in cognitive performance and, in particular, the decline of memory. Despite the increased longevity of the world’s population, the prevalence of neurodegenerative conditions, such as dementia, continues to be a major burden on public health, and consequently, the latest research has been focused on memory and aging. Currently, the failure of episodic and Prospective memory (PM) is one of the main complaints in the elderly, considered among the early symptoms of dementia. It is therefore increasingly important to define more clearly the boundaries between normal and pathological aging. Recently, researchers have begun to build and apply Virtual Environments (VE) to the explicit purpose of better understanding the performance of episodic and PM in complex and realistic contexts, with the perspective of further developing effective training procedures that depend on reliable cognitive assessment methods. Virtual technology offers higher levels of realism than “pen and paper” testing and at the same time more experimental control than naturalistic settings. In this mini-review article, we examine the outcomes of recently available studies on virtual reality technology applications developed for the assessment and improvement of episodic and/or PM. To consider the latest technology, we selected 29 articles that have been published in the last 10 years. These documents show that VR-based technologies can provide a valid basis for screening and treatment and, through increased sensory stimulation and enriched environments reproducing the scenarios of everyday life, could represent effective stimulating experiences even in pathological aging.

Pathological verbal repetition by Chinese elders with Dementia of Alzheimer’s Type

Verbal repetition has been acknowledged as one of the most common symptoms in early Dementia of Alzheimer's Type (DAT). Despite previous attempts, the applicability of verbal repetition as an essential linguistic marker indicating this disease remains unexplored for Chinese DAT patients. This study collects Chinese DAT patients' daily conversation data to investigate both structural and functional aspects of pathological verbal repetition. Three major types are set regarding the cases of pathological repetition, respectively ‘unconscious concept repetition', ‘perseveration', and ‘involuntary word repetition'. The analysis focuses on what features these repetitions have from the perspective of ‘ideational function', ‘interpersonal function', and ‘textual function' within the framework of Systemic Functional Linguistics. A better understanding of pathological verbal repetition by DAT elders as the linguistic markers of cognitive impairment promotes effective communication between patients, nursing staff, and family members.

Bilingualism Delays Expression of Alzheimer’s Clinical Syndrome

Objective: To evaluate the effects of bilingualism on the emergence of Alzheimer’s clinical syndrome. Background: Studies have proposed an increase in cognitive and neural reserve from the management and control of two languages, with a consequent delayed expression of dementia. Methods: In a clinic with a large immigrant population, we identified 253 patients with probable Alzheimer’s disease (AD) with intermediate or high evidence of AD pathophysiological process. These patients were reviewed for demographic variables, native language (L1) other than English, ages of onset and presentation, Mini-Mental State Examination (MMSE), digit spans, word fluencies, naming, and memory. Results: Among these patients, 74 (29.2%) were bilinguals with various L1s (Farsi, Spanish, Chinese, Tagalog, Arabic, others). When compared to the 179 monolingual AD patients, those who were bilingual had significant delays in ages of onset and presentation of approximately 4 years (p = 0.003). These delays persisted despite bilinguals having worse MMSE scores on presentation. There were no significant group differences on other variables except for worse naming in English among bilinguals versus monolinguals. Caregiver/informants reported that 66 (89.2%) of the 74 bilingual AD patients had gradually regressed to the predominant use of their L1. Conclusions: In line with published reports worldwide, we found that bilingualism delays the expression of Alzheimer’s clinical syndrome. We also found frequent reversion to the first learned language. These findings suggest that, among bilinguals, the availability of an L1 “back-up” either facilitates compensation or masks emergence of the early symptoms of dementia.

Human Activity Prediction using Long Short Term Memory

Early symptoms of dementia is one of the causes decrease in quality of life. Human activity recognition (HAR) system is proposed to recognize the daily routines which has an important role in detecting early symptoms of dementia. Long Short Term Memory (LSTM) is very useful for sequence analysis that can find the pattern of activities that carried out in daily routines. However, the LSTM model is slow to achieving convergence and take a long time during training. In this paper, we investigated the sequence of actions recorded in smart home sensors data using LSTM model, then the model will be optimized using several optimization methods. The optimization methods were Stochastic Gradient Descent (SGD), Adagrad, Adadelta, RMSProp, and Adam. The results showed that using Adam to optimized LSTM is better than other optimization methods.

Early Dementia Diagnosis Based on DNN Based Correlational Analysis and Fisher Criterion Based LDA using Morphological Brain Multiplexes

The expanding recurrence of dementia happening is a disturbing patterning that has incited dire research intending to avert the improvement of the sickness. Diagnosing dementia in its beginning periods is an urgent advance in averting the improvement of the ailment into exacerbated side effects. Early mild cognitive impairment (EMCI) is the early symptom of dementia. This can be analyzed using mapping mind associations utilizing Magnetic Resonance Imaging (MRI). In the approach, for improving the correlational block, we presented an enhanced classifier also, for improving the performance of discriminative block, an optimized LDA is to be proposed. For correlational analysis, Deep Neural Network (DNN) is presented in this work. Besides, for discriminative analysis, a novel and efficient feature selection method is presented. Fisher criterion is used to select the most discriminatory and appropriate features to ensure consistent feature selection and classifier learning goals and to improve the classifier's performance. In the Mat lab framework this proposed method is implemented. The performance of this proposed approach is evaluated concerning Accuracy, Sensitivity, and Specificity.

Long-Term Occupational Sleep Loss and Post-Retirement Cognitive Decline or Dementia

Introduction: Recent evidence suggests that poor sleep is a risk factor that contributes to the development of Alzheimer’s disease (AD). Most studies have focused on short-term effects of sleep deprivation on cognitive function, whereas longitudinal studies are limited to self-reported sleep and the risk of later-life dementia. Because sleep loss could be an early manifestation of neurodegenerative disease, reverse causality in these studies cannot be excluded. Objective: In this explorative, observational study, we investigated the effects of extended periods of extrinsically (work-related) caused sleep loss on later-life cognitive function, early dementia symptoms, and current sleep quality. Methods: We approached a community of retired male maritime pilots (approx. n = 500) through a newsletter. We investigated 50 respondents (mean age 71.7 years ± 7.7), with a history of >25 years of work on irregular schedules, which resulted in extended periods of sleep loss. Validated questionnaires on cognitive complaints (Cognitive Failure Questionnaire [CFQ]), early dementia symptoms (Early Dementia Questionnaire [EDQ]), current sleep quality (Pittsburgh Sleep Quality Index [PSQI] and sleep-wake diaries), quality of life (QoL, EQ-5D), and mood (Hospital Anxiety and Depression Scale [HADS]) were administered by a single investigator (J.T.), who also completed an observer rating of cognitive function. Results: Scores on the CFQ, EDQ, PSQI, EQ-5D, and HADS were within normal ranges adjusted for age, sex, and education. The observer rating was not indicative of cognitive decline. Conclusion: We found no evidence that long-term exposure to work-related sleep loss had resulted in cognitive decline or early dementia symptoms in this sample of retired maritime pilots.

Bilingualism and Dementia: Cognitive Reserve to Linguistic Competency.

Despite the large number of elderly bilinguals at risk for Alzheimer's disease (AD) and dementia worldwide, significant questions remain about the relationship between speaking more than one language and later cognitive decline. Bilingualism may impact on cognitive and neural reserve, time of onset of dementia symptoms and neuropathology, and linguistic competency in dementia. This review indicates increased cognitive reserve from executive (monitoring, selecting, inhibiting) control of two languages and increased neural reserve involving left frontal and related areas for language control. Many, but not all, studies indicate a delay in dementia symptom onset but worse hippocampal and mesiotemporal atrophy among bilinguals versus monolinguals with AD. In contrast, bilinguals do worse on language measures, and bilinguals with AD or dementia have difficulty maintaining and monitoring their second language. Together, these studies suggest that early-acquired and proficient bilingualism increases reserve through frontal-predominant executive control, and these executive abilities compensate for early dementia symptoms, delaying their onset but not the neuropathology of their disease. Finally, as executive control decreases further with advancing dementia, there is increasing difficulty inhibiting the dominant first language and staying in the second language. These conclusions must be interpreted with caution, given the problems inherent in this type of research; however, they do recommend more work on the pre-dementia neuroprotective effects and the dementia-related language impairments of bilingualism.

Epidemiology of neurocognitive disorders in France

Neurocognitive disorders are common: every year, any physician or health professional comes into contact with patients or relatives with early symptoms of dementia. Nevertheless, their epidemiology remains difficult to estimate, due to real differences in risk factors within a country or region (average age, genetics, level of education, socio-economic level, etc.), differences in data collection, in the interpretation of these data with regard to scientific findings and changes in diagnostic criteria. In this review, we present a state of knowledge of the epidemiology of dementia in France. Epidemiological data on neurocognitive disorders in France come mainly from 3 sources: two prospective cohorts (PAQUID and 3C) and large databases (SNIIRAM, RSI data, PMSI). Neurocognitive disorders are estimated to directly affect more than 1.2 million people in France and about 2 out of 3 cases are attributed to Alzheimer's disease. The prevalence rate is estimated at about 40/1,000 people after 60 years of age and gradually increases to 180/1,000 after 75 years of age, reaching almost one in two people after 90 years of age. The incidence rate is estimated at between 13 and 19/1,000 person-years, and seems to decrease slightly over the decades. The PAQUID and 3C cohorts are coming to an end; despite the development of large databases (SNIIRAM, PMSI, etc.), it seems necessary to continue to set up new prospective cohorts in the general population to monitor the epidemiology of neurocognitive disorders in France.