Fatigue in Alzheimer's disease: biological basis and clinical management-a narrative review

BACKGROUND

Fatigue is a common symptom in neurodegenerative diseases and is associated with decreased cognitive performances. A full knowledge of the causes and physiopathological pathways leading to fatigue in Alzheimer's disease could help treating this symptom and obtain positive effects on cognitive functions.

OBJECTIVES

To provide an overview of the clinical conditions and the biological mechanisms leading to fatigue in Alzheimer's disease patients. To review the recent advances on fatigue management and describe the landscape of future possibilities.

METHODS

We performed a narrative review including all type of studies (e.g. cross-sectional and longitudinal analysis, reviews, clinical trials).

RESULTS

We found very few studies considering the symptom fatigue in Alzheimer's disease patients. Populations, designs, and objectives varied across studies rendering comparability across studies difficult to perform. Results from cross-sectional and longitudinal analysis suggest that the amyloid cascade may be involved in the pathogenesis of fatigue and that fatigue may be a prodromal manifestation of Alzheimer's disease. Fatigue and neurodegeneration of Alzheimer's disease could share common brain signatures (i.e. hippocampal atrophy and periventricular leukoaraiosis). Some mechanisms of aging (i.e. inflammation, mitochondrial dysfunction, telomere shortening) may be proposed to play a common underlying role in Alzheimer's disease neurodegeneration and muscle fatigability. Considering treatments, donepezil has been found to reduce cognitive fatigue in a 6-week randomized controlled study. Fatigue is frequently reported as an adverse event in patients treated by anti-amyloid agents in clinical trials.

CONCLUSION

The literature is actually inconclusive about the main causes of fatigue in Alzheimer's disease individuals and its potential treatments. Further research is needed to disentangle the role of several components such as comorbidities, depressive symptoms, iatrogenic factors, physical decline and neurodegeneration itself. Given the clinical relevance of this symptom, it seems to be important to systematically assess fatigue by validated tools in Alzheimer's disease clinical trials.

Validity and Performance of Blood Biomarkers for Alzheimer Disease to Predict Dementia Risk in a Large Clinic-Based Cohort

BACKGROUND AND OBJECTIVE

Blood biomarkers for Alzheimer disease (AD) have consistently proven to be associated with CSF or PET biomarkers and effectively discriminate AD from other neurodegenerative diseases. Our aim was to test their utility in clinical practice, from a multicentric unselected prospective cohort where patients presented with a large spectrum of cognitive deficits or complaints.

METHODS

The MEMENTO cohort enrolled 2,323 outpatients with subjective cognitive complaint (SCC) or mild cognitive impairment (MCI) consulting in 26 French memory clinics. Participants had neuropsychological assessments, MRI, and blood sampling at baseline. CSF sampling and amyloid PET were optional. Baseline blood Aβ42/40 ratio, total tau, p181-tau, and neurofilament light chain (NfL) were measured using a Simoa HD-X analyzer. An expert committee validated incident dementia cases during a 5-year follow-up period.

RESULTS

Overall, 2,277 individuals had at least 1 baseline blood biomarker available (n = 357 for CSF subsample, n = 649 for PET subsample), among whom 257 were diagnosed with clinical AD/mixed dementia during follow-up. All blood biomarkers but total tau were mildly correlated with their equivalence in the CSF (r = 0.33 to 0.46, p < 0.0001) and were associated with amyloid-PET status (p < 0.0001). Blood p181-tau was the best blood biomarker to identify amyloid-PET positivity (area under the curve = 0.74 [95% CI = 0.69; 0.79]). Higher blood and CSF p181-tau and NfL concentrations were associated with accelerated time to AD dementia onset with similar incidence rates, whereas blood Aβ42/40 was less efficient than CSF Aβ42/40. Blood p181-tau alone was the best blood predictor of 5-year AD/mixed dementia risk (c-index = 0.73 [95% CI = 0.69; 0.77]); its accuracy was higher in patients with clinical dementia rating (CDR) = 0 (c-index = 0.83 [95% CI = 0.69; 0.97]) than in patients with CDR = 0.5 (c-index = 0.70 [95% CI = 0.66; 0.74]). A "clinical" reference model (combining demographics and neuropsychological assessment) predicted AD/mixed dementia risk with a c-index = 0.88 [95% CI = 0.86-0.91] and performance increased to 0.90 [95% CI = 0.88; 0.92] when adding blood p181-tau + Aβ42/40. A "research" reference model (clinical model + apolipoprotein E genotype and AD signature on MRI) had a c-index = 0.91 [95% CI = 0.89-0.93] increasing to 0.92 [95% CI = 0.90; 0.93] when adding blood p181-tau + Aβ42/40. Chronic kidney disease and vascular comorbidities did not affect predictive performances.

DISCUSSION

In a clinic-based cohort of patients with SCC or MCI, blood biomarkers may be good hallmarks of underlying pathology but add little to 5-year dementia risk prediction models including traditional predictors.

Different Trajectories of Apathy and Depression Among Subjective Cognitive Impairment Individuals with or without Conversion to Dementia: Results from the Memento Cohort in France

BACKGROUND

Apathy and depression are two early behavioral symptoms in Alzheimer's disease (AD) and related disorders that often occur prior to the onset of cognitive decline and memory disturbances. Both have been associated with an increased risk of conversion to dementia, with a distinct neuropathology.

OBJECTIVE

The assessment of the trajectories of apathy and depression and their independent impact on dementia conversion.

METHODS

Apathy and Depression were measured using the Neuropsychiatric Inventory for caregiver (NPI) and clinician (NPI-C), among the nondemented individuals reporting subjective cognitive decline (SCD) at baseline. They were followed up over a 60-month period. Some converted to dementia, according to the methodology carried out by the French Memento Cohort.

RESULTS

Among individuals with SCD (n = 2,323), the levels of apathy and depression were low and did not evolve significantly over the 60-month period, despite a trend in apathy increasing as of month 24. Regarding SCD individuals who converted to dementia within the 60-month period (n = 27), the prevalence of depression remained globally steady, while the levels of apathy increased over time.

CONCLUSION

Apathy and depression have different trajectories among individuals with SCD and apathy alone is more likely-compared to depression-to be associated with conversion to dementia.

Plasma MCP-1 and changes on cognitive function in community-dwelling older adults

Background

Monocyte Chemoattractant Protein-1 (MCP-1), a glial-derived chemokine, mediates neuroinflammation and may regulate memory outcomes among older adults. We aimed to explore the associations of plasma MCP-1 levels (alone and in combination with β-amyloid deposition—Aβ_42/40) with overall and domain-specific cognitive evolution among older adults.

Methods

Secondary analyses including 1097 subjects (mean age = 75.3 years ± 4.4; 63.8% women) from the Multidomain Alzheimer Preventive Trial (MAPT). MCP-1 (higher is worse) and Aβ_42/40 (lower is worse) were measured in plasma collected at year 1. MCP-1 in continuous and as a dichotomy (values in the highest quartile (MCP-1⁺)) were used, as well as a dichotomy of Aβ_42/40. Outcomes were measured annually over 4 years and included the following: cognitive composite z-score (CCS), the Mini-Mental State Examination (MMSE), and Clinical Dementia Rating (CDR) sum of boxes (overall cognitive function); composite executive function z-score, composite attention z-score, Free and Cued Selective Reminding Test (FCSRT - memory).

Results

Plasma MCP-1 as a continuous variable was associated with the worsening of episodic memory over 4 years of follow-up, specifically in measures of free and cued delayed recall. MCP-1⁺ was associated with worse evolution in the CCS (4-year between-group difference: β = −0.14, 95%CI = −0.26, −0.02) and the CDR sum of boxes (2-year: β = 0.19, 95%CI = 0.06, 0.32). In domain-specific analyses, MCP-1⁺ was associated with declines in the FCSRT delayed recall sub-domains. In the presence of low Aβ_42/40, MCP-1⁺ was not associated with greater declines in cognitive functions. The interaction with continuous biomarker values Aβ_42/40× MCP-1 × time was significant in models with CDR sum of boxes and FCSRT DTR as dependent variables.

Conclusions

Baseline plasma MCP-1 levels were associated with longitudinal declines in overall cognitive and episodic memory performance in older adults over a 4-year follow-up. How plasma MCP-1 interacts with Aβ_42/40 to determine cognitive decline at different stages of cognitive decline/dementia should be clarified by further research. The MCP-1 association on cognitive decline was strongest in those with amyloid plaques, as measured by blood plasma Aβ_42/40.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00940-2.

Biomarkers of mitochondrial dysfunction and inflammaging in older adults and blood pressure variability

Most physiopathological mechanisms underlying blood pressure variability (BPV) are implicated in aging. Vascular aging is associated with chronic low-grade inflammation occurring in late life, known as "inflammaging" and the hallmark "mitochondrial dysfunction" due to age-related stress. We aimed to determine whether plasma levels of the pleiotropic stress-related mitokine growth/differentiation factor 15 (GDF-15) and two inflammatory biomarkers, interleukin 6 (IL-6) and tumor necrosis factor receptor 1 (TNFR-1), are associated with visit-to-visit BPV in a population of community-dwelling older adults. The study population consisted of 1096 community-dwelling participants [median age 75 (72-78) years; 699 females, 63.7%] aged ≥ 70 years from the MAPT study. Plasma blood sample was collected 12 months after enrolment and BP was assessed up to seven times over a 4-year period. Systolic (SBPV) and diastolic BPV (DBPV) were determined through several indicators taking into account BP change over time, the order of measurements and formulas independent of mean BP levels. Higher values of GDF-15 were significantly associated with increased SBPV (all indicators) after adjustment for relevant covariates [adjusted 1-SD increase in GDF-15: β (SE) = 0.07 (0.04), p < 0.044, for coefficient of variation%]. GDF-15 levels were not associated with DBPV. No significant associations were found between IL-6 and BPV, whereas TNFR1 was only partially related to DBPV. Unlike inflammation biomarkers, higher GDF-15 levels were associated with greater SBPV. Our findings support the age-related process of mitochondrial dysfunction underlying BP instability, suggesting that BPV might be a potential marker of aging.

Cognitive decline as an outcome and marker of progression toward dementia, in early preventive trials

INTRODUCTION

Recent Food and Drug Administration guidance endorses cognitive assessment as a possible primary endpoint for early trials for Alzheimer's disease but emphasizes the need for certainty regarding the relationship with progression to dementia.

METHODS

We compared the validity of the 2-year change (Y0-Y2) of 11 markers of neuropsychological and functional abilities for the prediction of incident dementia over the following 3 years (Y2-Y5), in 860 subjects aged 70 years or older, who consulted for memory loss and were included in the "GuidAge" prevention trial.

RESULTS

The Free and Cued Selective Reminding Test-Free Recall (FCSRT-FR) score showed the most predictive 2-year change (area under the curve = 0.72 95% confidence interval = 0.64;0.81). Changes in other subscores of the FCSRT, verbal fluencies tasks, and composite cognitive score were also significantly predictive. Conversely, 2-year change of Mini-Mental State Examination, Trail Making test (TMT)-A, TMT-B, Clinical Dementia Rating Sum of Boxes, and Instrumental Activities of Daily Living scores did not significantly predict occurrence of dementia.

CONCLUSION

The FCSRT, the Fluency Task, and the composite cognitive score appear to be good cognitive markers of progression toward dementia in early prevention trials.

Diabetes Mellitus and Cognition: Pathway Analysis in the MEMENTO Cohort

OBJECTIVE

To assess the role of biomarkers of Alzheimer disease (AD), neurodegeneration, and small vessel disease (SVD) as mediators in the association between diabetes mellitus and cognition.

METHODS

The study sample was derived from MEMENTO, a cohort of French adults recruited in memory clinics and screened for either isolated subjective cognitive complaints or mild cognitive impairment. Diabetes was defined based on blood glucose assessment, use of antidiabetic agent, or self-report. We used structural equation modeling to assess whether latent variables of AD pathology (PET mean amyloid uptake, Aβ42/Aβ40 ratio, and CSF phosphorylated tau), SVD (white matter hyperintensities volume and visual grading), and neurodegeneration (mean cortical thickness, brain parenchymal fraction, hippocampal volume, and mean fluorodeoxyglucose uptake) mediate the association between diabetes and a latent variable of cognition (5 neuropsychological tests), adjusting for potential confounders.

RESULTS

There were 254 (11.1%) participants with diabetes among 2,288 participants (median age 71.6 years; 61.8% women). The association between diabetes and lower cognition was significantly mediated by higher neurodegeneration (standardized indirect effect: -0.061, 95% confidence interval: -0.089, -0.032), but not mediated by SVD and AD markers. Results were similar when considering latent variables of memory or executive functioning.

CONCLUSION

In a large clinical cohort in the elderly, diabetes is associated with lower cognition through neurodegeneration, independently of SVD and AD biomarkers.

Development and Validation of a Model to Identify Alzheimer's Disease and Related Syndromes in Administrative Data

BACKGROUND

Administrative data are used in the field of Alzheimer's Disease and Related Syndromes (ADRS), however their performance to identify ADRS is unknown.

OBJECTIVE

i) To develop and validate a model to identify ADRS prevalent cases in French administrative data (SNDS), ii) to identify factors associated with false negatives.

METHODS

Retrospective cohort of subjects ≥ 65 years, living in South-Western France, who attended a memory clinic between April and December 2013. Gold standard for ADRS diagnosis was the memory clinic specialized diagnosis. Memory clinics' data were matched to administrative data (drug reimbursements, diagnoses during hospitalizations, registration with costly chronic conditions). Prediction models were developed for 1-year and 3-year periods of administrative data using multivariable logistic regression models. Overall model performance, discrimination, and calibration were estimated and corrected for optimism by resampling. Youden index was used to define ADRS positivity and to estimate sensitivity, specificity, positive predictive and negative probabilities. Factors associated with false negatives were identified using multivariable logistic regressions.

RESULTS

3360 subjects were studied, 52% diagnosed with ADRS by memory clinics. Prediction model based on age, all-cause hospitalization, registration with ADRS as a chronic condition, number of anti-dementia drugs, mention of ADRS during hospitalizations had good discriminative performance (c-statistic: 0.814, sensitivity: 76.0%, specificity: 74.2% for 2013 data). 419 false negatives (24.0%) were younger, had more often ADRS types other than Alzheimer's disease, moderate forms of ADRS, recent diagnosis, and suffered from other comorbidities than true positives.

CONCLUSION

Administrative data presented acceptable performance for detecting ADRS. External validation studies should be encouraged.

Cognitive Function and Amyloid Marker in Frail Older Adults: The COGFRAIL Cohort Study

BACKGROUND

Frailty and cognitive impairment are common manifestations of the ageing process and are closely related. But the mechanisms linking aging, physical frailty, and cognitive disorders, are complex and remain unclear.

OBJECTIVES

We aim to explore the role of cerebral amyloid pathology, but also a range of nutritional, physical, biological or brain-aging marker in the development of cognitive frailty.

METHOD

COGFRAIL study is a monocentric prospective study of frail older patients with an objective cognitive impairment (Clinical Dementia Rating Scale global score at 0.5 or 1). Three-hundred-and-twenty-one patients are followed up every 6 months, for 2 years. Clinical assessment at baseline and during follow-up included frailty, physical, mood, sensory, nutritional, and cognitive assessment (with a set of neuropsychological tests). Cerebral amyloid pathology is measured by amyloid Positron Emission Tomography (PET) or amyloid-β-1-42 level in cerebrospinal fluid. Brain magnetic resonance imaging, measurement of body composition using Dual X Ray Absorptiometry and blood sampling are performed. The main outcome of the study is to assess the prevalence of positive cerebral amyloid status according to amyloid PET or amyloid-β-1-42 level CSF. Secondary outcomes included biological, nutritional, MRI imaging, cognitive, clinical, physical and body composition markers to better understand the mechanisms of cognitive frailty.

PERSPECTIVE

COGFRAIL study will give the opportunity to better understand the link between Gerosciences, frailty, cognitive impairment, and Alzheimer's disease, and to better characterize the physical and cognitive trajectories of frail older adults according to their amyloid status. Understanding the relationship between physical frailty and cognitive impairment is a prerequisite for the development of new interventions that could prevent and treat both conditions.

Biomarker counseling, disclosure of diagnosis and follow-up in patients with mild cognitive impairment: A European Alzheimer's disease consortium survey

OBJECTIVES

Mild cognitive impairment (MCI) is associated with an increased risk of further cognitive decline, partly depending on demographics and biomarker status. The aim of the present study was to survey the clinical practices of physicians in terms of biomarker counseling, management, and follow-up in European expert centers diagnosing patients with MCI.

METHODS

An online email survey was distributed to physicians affiliated with European Alzheimer's disease Consortium centers (Northern Europe: 10 centers; Eastern and Central Europe: 9 centers; and Southern Europe: 15 centers) with questions on attitudes toward biomarkers and biomarker counseling in MCI and dementia. This included postbiomarker counseling and the process of diagnostic disclosure of MCI, as well as treatment and follow-up in MCI.

RESULTS

The response rate for the survey was 80.9% (34 of 42 centers) across 20 countries. A large majority of physicians had access to biomarkers and found them useful. Pre- and postbiomarker counseling varied across centers, as did practices for referral to support groups and advice on preventive strategies. Less than half reported discussing driving and advance care planning with patients with MCI.

CONCLUSIONS

The variability in clinical practices across centers calls for better biomarker counseling and better training to improve communication skills. Future initiatives should address the importance of communicating preventive strategies and advance planning.

Kidney Function and Cognitive Decline in Older Adults: Examining the Role of Neurodegeneration

BACKGROUND/OBJECTIVES

Cognitive decline associated with impaired kidney function might involve neurodegeneration. Our objectives were to evaluate the longitudinal association between kidney function and cognitive decline in older adults and to assess the involvement of cortical beta-amyloid and hippocampal atrophy (features of Alzheimer's disease (AD)) in this association.

DESIGN

Secondary analysis of the randomized controlled Multidomain Alzheimer Preventive Trial (MAPT).

SETTINGS

Thirteen memory centers (France and Monaco, 2008-2016).

PARTICIPANTS

A total of 1,334 community-dwellers >70 years old without dementia at baseline.

MEASUREMENTS

We estimated glomerular filtration rate (eGFR) from serum creatinine using CKD-Epi equation. Cognition was assessed at baseline, 6, 12, 24, 36, 48, and 60 months using a composite Z-score designed for MAPT. The Clinical Dementia Rating (CDR) score was used to assess cognition and functional independence. We examined the association between eGFR and (1) evolution of the composite cognitive Z-score using mixed-effect models and (2) progression on CDR using Cox models and mixed-effect models. Adjustments were made for age, sex, education, ApoE genotype, cardiovascular risk factors and disease, hippocampal volume (measured with magnetic resonance), and cortical beta-amyloid (measured with positron emission tomography).

RESULTS

Median (IQR) eGFR was 73(60-84) mL/min/1.73 m² . Two hundred sixty-nine participants experienced progression on CDR score during follow-up. eGFR<60 was significantly associated with progression on CDR score (adjusted hazard ratio (aHR) = 1.35, 95% CI 1.01-1.80) and with both the cognitive and functional independence components of CDR, but not with the evolution of the composite cognitive Z-score (adjusted β-coefficient -0.004, 95% CI -0.014; 0.006). Associations were not modified after further adjustment for beta-amyloid (subsample: n = 252) and hippocampal volume (subsample: n = 270).

CONCLUSIONS

We did not find a mild to moderate renal insufficiency to be associated with brain imaging features of AD, and our results do not support the involvement of AD mechanisms in the incidence of cognitive impairment and functional decline associated with chronic kidney disease.

Viewpoint: Impact of the Covid-19 Outbreak on the Clinical and Research Activities of Memory Clinics: An Alzheimer's Disease Center Facing the Covid-19 Crisis

The 2020 Coronavirus pandemic is the greatest global health crisis we have had in recent decades, both by its own consequences and by the impact of the measures that have been taken by various countries to deal with it (1). The effect is major on Western health systems, affecting all areas of care and research, including research on Alzheimer’s disease and cognitive aging.

Prescreening for European Prevention of Alzheimer Dementia (EPAD) trial-ready cohort: impact of AD risk factors and recruitment settings

BACKGROUND

Recruitment is often a bottleneck in secondary prevention trials in Alzheimer disease (AD). Furthermore, screen-failure rates in these trials are typically high due to relatively low prevalence of AD pathology in individuals without dementia, especially among cognitively unimpaired. Prescreening on AD risk factors may facilitate recruitment, but the efficiency will depend on how these factors link to participation rates and AD pathology. We investigated whether common AD-related factors predict trial-ready cohort participation and amyloid status across different prescreen settings.

METHODS

We monitored the prescreening in four cohorts linked to the European Prevention of Alzheimer Dementia (EPAD) Registry (n = 16,877; mean ± SD age = 64 ± 8 years). These included a clinical cohort, a research in-person cohort, a research online cohort, and a population-based cohort. Individuals were asked to participate in the EPAD longitudinal cohort study (EPAD-LCS), which serves as a trial-ready cohort for secondary prevention trials. Amyloid positivity was measured in cerebrospinal fluid as part of the EPAD-LCS assessment. We calculated participation rates and numbers needed to prescreen (NNPS) per participant that was amyloid-positive. We tested if age, sex, education level, APOE status, family history for dementia, memory complaints or memory scores, previously collected in these cohorts, could predict participation and amyloid status.

RESULTS

A total of 2595 participants were contacted for participation in the EPAD-LCS. Participation rates varied by setting between 3 and 59%. The NNPS were 6.9 (clinical cohort), 7.5 (research in-person cohort), 8.4 (research online cohort), and 88.5 (population-based cohort). Participation in the EPAD-LCS (n = 413 (16%)) was associated with lower age (odds ratio (OR) age = 0.97 [0.95-0.99]), high education (OR = 1.64 [1.23-2.17]), male sex (OR = 1.56 [1.19-2.04]), and positive family history of dementia (OR = 1.66 [1.19-2.31]). Among participants in the EPAD-LCS, amyloid positivity (33%) was associated with higher age (OR = 1.06 [1.02-1.10]) and APOE ɛ4 allele carriership (OR = 2.99 [1.81-4.94]). These results were similar across prescreen settings.

CONCLUSIONS

Numbers needed to prescreen varied greatly between settings. Understanding how common AD risk factors link to study participation and amyloid positivity is informative for recruitment strategy of studies on secondary prevention of AD.

Duration of preclinical, prodromal, and dementia stages of Alzheimer's disease in relation to age, sex, and APOE genotype

INTRODUCTION

We estimated the age-specific duration of the preclinical, prodromal, and dementia stages of Alzheimer's disease (AD) and the influence of sex, setting, apolipoprotein E (APOE) genotype, and cerebrospinal fluid tau on disease duration.

METHODS

We performed multistate modeling in a combined sample of 6 cohorts (n = 3268) with death as the end stage and estimated the preclinical, prodromal, and dementia stage duration.

RESULTS

The overall AD duration varied between 24 years (age 60) and 15 years (age 80). For individuals presenting with preclinical AD, age 70, the estimated preclinical AD duration was 10 years, prodromal AD 4 years, and dementia 6 years. Male sex, clinical setting, APOE ε4 allele carriership, and abnormal cerebrospinal fluid tau were associated with a shorter duration, and these effects depended on disease stage.

DISCUSSION

Estimates of AD disease duration become more accurate if age, sex, setting, APOE, and cerebrospinal fluid tau are taken into account. This will be relevant for clinical practice and trial design.

The ROSAS Cohort: A Prospective, Longitudinal Study of Biomarkers for Alzheimer's Disease. Strategy, Methods and Initial Results

OBJECTIVE

The aims of the Research Of biomarkers in Alzheimer's diseaSe (ROSAS) study were to determine the biofluid and imaging biomarkers permitting an early diagnosis of Alzheimer's disease and better characterisation of cognitive and behavioural course of the pathology. This paper outlines the overall strategy, methodology of the study, baseline characteristics of the population and first longitudinal results from the ROSAS cohort.

METHODS

Longitudinal prospective monocentric observational study performed at the Alzheimer's disease Research centre in Toulouse. A total of 387 patients were studied and analyzed in 3 groups: 184 patients with dementia of Alzheimer's type, 96 patients with memory disorders without dementia (Mild Cognitive Impairment) and 107 patients without abnormal memory tests (control group), and were followed up during 4 years. Patient's sociodemographic characteristics, risk factors, medical conditions, previous and current medications, neuropsychological assessment and overall cognitive status were recorded. Blood and urine samples were collected at every year, Magnetic Resonance Imaging were performed at inclusion, after one year of follow-up and at the end of the study.

RESULTS

At baseline, three different groups of the cohort differed interestingly in age, level of education, and in percentage of ApoEε4 carriers whereas the history of cardiovascular and endocrine pathologies were similar among the groups. During the follow-up period (3-4 years) 42 mild cognitive impairment patients (43.8%) progressed to dementia, 7 controls progressed into mild cognitive impairment and 1 patient in the control group converted from mild cognitive impairment group to dementia of Alzheimer's type group. During the first year of follow up, the incidence of progression from mild cognitive impairment to dementia of Alzheimer's type was 12.7 per 100, during the second year 33.9 per 100 and 46.7 per 100 for the third year.

CONCLUSION

This paper presents the baseline characteristics of the unique French prospective monocenter study in which the natural course of dementia of Alzheimer's type was evaluated. Future analysis of blood and urine samples collection from the ROSAS study will permit to identify possible biofluid biomarkers predicting the early stages of the dementia of Alzheimer's type and risk of progression from Mild Cognitive Impairment to Alzheimer's disease.

A web-based multidomain lifestyle intervention with connected devices for older adults: research protocol of the eMIND pilot randomized controlled trial

BACKGROUND

Multidomain interventions composed of nutritional counseling, exercise and cognitive trainings have shown encouraging results as effective preventive strategies delaying age-related declines. However, these interventions are time- and resource-consuming. The use of Information and Communication Technologies (ICT) might facilitate the translation from research into real-world practice and reach a massive number of people.

AIM

This article describes the protocol of the eMIND study, a randomized controlled trial (RCT) using a web-based multidomain intervention for older adults.

METHODS

One hundred and twenty older adults (≥ 65 years), with a spontaneous memory complaint, will be randomly assigned to a six-month web-based multidomain (nutritional counseling, physical and cognitive trainings) intervention group with a connected accelerometer (number of steps, energy expenditure), or to a control group with access to general information on healthy aging plus the accelerometer, but no access to the multidomain intervention. The main outcome is the feasibility/acceptability of the web-based intervention. Secondary clinical outcomes include: cognitive functions, physical performance, nutritional status and cost-effectiveness.

RESULTS

We expect a high amount of adherers (ie, > 75% compliance to the protocol) to reflect the feasibility. Acceptability, assessed through interviews, should allow us to understand motivators and barriers to this ICT intervention. We also expect to provide data on its effects on various clinical outcomes and efficiency.

CONCLUSION AND DISCUSSION

The eMIND study will provide crucial information to help developing a future and larger web-based multidomain lifestyle RCT, which should facilitate the translation of this ICT intervention from the research world into real-life clinical practice for the healthcare of older adults.

European Prevention of Alzheimer's Dementia Registry: Recruitment and prescreening approach for a longitudinal cohort and prevention trials

INTRODUCTION

It is a challenge to find participants for Alzheimer's disease (AD) prevention trials within a short period of time. The European Prevention of Alzheimer's Dementia Registry (EPAD) aims to facilitate recruitment by preselecting subjects from ongoing cohort studies. This article introduces this novel approach.

METHODS

A virtual registry, with access to risk factors and biomarkers for AD through minimal data sets of ongoing cohort studies, was set up.

RESULTS

To date, ten cohorts have been included in the EPAD. Around 2500 participants have been selected, using variables associated with the risk for AD. Of these, 15% were already recruited in the EPAD longitudinal cohort study, which serves as a trial readiness cohort.

DISCUSSION

This study demonstrates that a virtual registry can be used for the preselection of participants for AD studies.

Increased Aβ42-α7-like nicotinic acetylcholine receptor complex level in lymphocytes is associated with apolipoprotein E4-driven Alzheimer's disease pathogenesis

BACKGROUND

The apolipoprotein E ε4 (APOE4) genotype is a prominent late-onset Alzheimer's disease (AD) risk factor. ApoE4 disrupts memory function in rodents and may contribute to both plaque and tangle formation.

METHODS

Coimmunoprecipitation and Western blot detection were used to determine: 1) the effects of select fragments from the apoE low-density lipoprotein (LDL) binding domain and recombinant apoE subtypes on amyloid beta (Aβ)₄₂-α7 nicotinic acetylcholine receptor (α7nAChR) interaction and tau phosphorylation in rodent brain synaptosomes; and 2) the level of Aβ₄₂-α7nAChR complexes in matched controls and patients with mild cognitive impairment (MCI) and dementia due to AD with known APOE genotypes.

RESULTS

In an ex vivo study using rodent synaptosomes, apoE_141-148 of the apoE promotes Aβ₄₂-α7nAChR association and Aβ₄₂-induced α7nAChR-dependent tau phosphorylation. In a single-blind study, we examined lymphocytes isolated from control subjects, patients with MCI and dementia due to AD with known APOE genotypes, sampled at two time points (1 year apart). APOE ε4 genotype was closely correlated with heightened Aβ₄₂-α7nAChR complex levels and with blunted exogenous Aβ₄₂ effects in lymphocytes derived from AD and MCI due to AD cases. Similarly, plasma from APOE ε4 carriers enhanced the Aβ₄₂-induced Aβ₄₂-α7nAChR association in rat cortical synaptosomes. The progression of cognitive decline in APOE ε4 carriers correlated with higher levels of Aβ₄₂-α7nAChR complexes in lymphocytes and greater enhancement by their plasma of Aβ₄₂-induced Aβ₄₂-α7nAChR association in rat cortical synaptosomes.

CONCLUSIONS

Our data suggest that increased lymphocyte Aβ₄₂-α7nAChR-like complexes may indicate the presence of AD pathology especially in APOE ε4 carriers. We show that apoE, especially apoE4, promotes Aβ₄₂-α7nAChR interaction and Aβ₄₂-induced α7nAChR-dependent tau phosphorylation via its apoE_141-148 domain_. These apoE-mediated effects may contribute to the APOE ε4-driven neurodysfunction and AD pathologies.

Effect of long-term omega 3 polyunsaturated fatty acid supplementation with or without multidomain intervention on cognitive function in elderly adults with memory complaints (MAPT): a randomised, placebo-controlled trial

BACKGROUND

No large trials have been done to investigate the efficacy of an intervention combining a specific compound and several lifestyle interventions compared with placebo for the prevention of cognitive decline. We tested the effect of omega 3 polyunsaturated fatty acid supplementation and a multidomain intervention (physical activity, cognitive training, and nutritional advice), alone or in combination, compared with placebo, on cognitive decline.

METHODS

The Multidomain Alzheimer Preventive Trial was a 3-year, multicentre, randomised, placebo-controlled superiority trial with four parallel groups at 13 memory centres in France and Monaco. Participants were non-demented, aged 70 years or older, and community-dwelling, and had either relayed a spontaneous memory complaint to their physician, limitations in one instrumental activity of daily living, or slow gait speed. They were randomly assigned (1:1:1:1) to either the multidomain intervention (43 group sessions integrating cognitive training, physical activity, and nutrition, and three preventive consultations) plus omega 3 polyunsaturated fatty acids (ie, two capsules a day providing a total daily dose of 800 mg docosahexaenoic acid and 225 mg eicosapentaenoic acid), the multidomain intervention plus placebo, omega 3 polyunsaturated fatty acids alone, or placebo alone. A computer-generated randomisation procedure was used to stratify patients by centre. All participants and study staff were blinded to polyunsaturated fatty acid or placebo assignment, but were unblinded to the multidomain intervention component. Assessment of cognitive outcomes was done by independent neuropsychologists blinded to group assignment. The primary outcome was change from baseline to 36 months on a composite Z score combining four cognitive tests (free and total recall of the Free and Cued Selective Reminding test, ten Mini-Mental State Examination orientation items, Digit Symbol Substitution Test, and Category Naming Test) in the modified intention-to-treat population. The trial was registered with ClinicalTrials.gov (NCT00672685).

FINDINGS

1680 participants were enrolled and randomly allocated between May 30, 2008, and Feb 24, 2011. In the modified intention-to-treat population (n=1525), there were no significant differences in 3-year cognitive decline between any of the three intervention groups and the placebo group. Between-group differences compared with placebo were 0·093 (95% CI 0·001 to 0·184; adjusted p=0·142) for the combined intervention group, 0·079 (-0·012 to 0·170; 0·179) for the multidomain intervention plus placebo group, and 0·011 (-0·081 to 0·103; 0·812) for the omega 3 polyunsaturated fatty acids group. 146 (36%) participants in the multidomain plus polyunsaturated fatty acids group, 142 (34%) in the multidomain plus placebo group, 134 (33%) in the polyunsaturated fatty acids group, and 133 (32%) in the placebo group had at least one serious emerging adverse event. Four treatment-related deaths were recorded (two in the multidomain plus placebo group and two in the placebo group). The interventions did not raise any safety concerns and there were no differences between groups in serious or other adverse events.

INTERPRETATION

The multidomain intervention and polyunsaturated fatty acids, either alone or in combination, had no significant effects on cognitive decline over 3 years in elderly people with memory complaints. An effective multidomain intervention strategy to prevent or delay cognitive impairment and the target population remain to be determined, particularly in real-world settings.

FUNDING

French Ministry of Health, Pierre Fabre Research Institute, Gerontopole, Exhonit Therapeutics, Avid Radiopharmaceuticals.

Evaluating the clinical relevance of a cognitive composite outcome measure: An analysis of 1414 participants from the 5-year GuidAge Alzheimer's prevention trial

INTRODUCTION

Composite cognitive scores have been developed as primary outcome measures for preclinical/prevention trials for Alzheimer's disease (AD), mainly using observational data and with little consideration of clinical relevance.

METHODS

Secondary analysis of placebo group data from a 5-year AD prevention trial. The composite score was the average of the following z scores: MMSE orientation items, Free and Cued Selective Reminding Test, Category Fluency, Trail Making Test-part B.

RESULTS

Composite score change from baseline differed significantly by age, APOE genotype, and CDR progression and AD dementia status. A 1 point decrease in baseline score was highly predictive of 5-year AD dementia risk (HR = 3.51, 95% CI, 2.62-4.71, P < .001). The 1 year minimum clinically important difference was estimated at -0.3 points and predicted AD dementia.

DISCUSSION

We explored the clinical relevance of a composite score in a prevention trial setting. This type of analysis facilitates the interpretation of composite scores and informs power calculations.

Frailty and Cognition

Frailty is a common, heterogeneous, geriatric syndrome associated with adverse health events. Over the last years, a growing debate has emerged concerning the inclusion of cognitive impairment in the definition of frailty. In fact, cognitive impairment has been increasingly recognized as a potential contributor to the clinical vulnerability of older persons. This review presents key studies describing the interrelationships between cognition and frailty; in particular we examine the clinical relevance of cognitive impairment in the determination of the frailty syndrome.

Analysing Time to Event Data in Dementia Prevention Trials: The Example of the GuidAge Study of EGb761

Time-to-event analysis is frequently used in medical research to investigate potential disease-modifying treatments in neurodegenerative diseases. Potential treatment effects are generally evaluated using the logrank test, which has optimal power and sensitivity when the treatment effect (hazard ratio) is constant over time. However, there is generally no prior information as to how the hazard ratio for the event of interest actually evolves. In these cases, the logrank test is not necessarily the most appropriate to use. When the hazard ratio is expected to decrease or increase over time, alternative statistical tests such as the Fleming-Harrington test, provide a better sensitivity. An example of this comes from a large, five-year randomised, placebo-controlled prevention trial (GuidAge) in 2854 community-based subjects making spontaneous memory complaints to their family physicians, which evaluated whether treatment with EGb761 can modify the risk of developing AD. The primary outcome measure was the time to conversion from memory complaint to Alzheimer's type dementia. Although there was no significant difference in the hazard function of conversion between the two treatment groups according to the preplanned logrank test, a significant treatment-by-time interaction for the incidence of AD was observed in a protocol-specified subgroup analysis, suggesting that the hazard ratio is not constant over time. For this reason, additional post hoc analyses were performed using the Fleming-Harrington test to evaluate whether there was a signal of a late effect of EGb761. Applying the Fleming-Harrington test, the hazard function for conversion to dementia in the placebo group was significantly different from that in the EGb761 treatment group (p = 0.0054), suggesting a late effect of EGb761. Since this was a post hoc analysis, no definitive conclusions can be drawn as to the effectiveness of the treatment. This post hoc analysis illustrates the interest of performing another randomised clinical trial of EGb761 explicitly testing the hypothesis of a late treatment effect, as well as of using of better adapted statistical approaches for long term preventive trials when it is expected that prevention cannot have an immediate effect but rather a delayed effect that increases over time.

Brain Amyloid Deposition Is Associated With Lower Instrumental Activities of Daily Living Abilities in Older Adults. Results From the MAPT Study

BACKGROUND

Brain amyloid deposition is one of the key pathological hallmarks underlying the cognitive changes associated with Alzheimer's disease. Growing interest has been given to the earliest clinical manifestations of amyloid plaques. However, the relationship between amyloid status and activities of everyday function remains largely unknown. In the present study, we examined the relationship between instrumental activities of daily living performance (using the ADL-PI score) and amyloid status in older adults.

METHODS

Cross-sectional analyses of data from the Multidomain Alzheimer Preventive Trial (MAPT) were performed. Volunteers underwent a brain 18F-AV45 positron emission tomography examination. Bivariate analysis and regression models were conducted to study the relationships between brain amyloid deposition and the total ADL-PI score.

RESULTS

We included 271 participants (women = 60%; age = 76±4 years). Amyloid positron emission tomography was positive (standard uptake value ≥1.17) for 103 participants (38%). The ADL-PI score was lower in amyloid positive participants than in their amyloid negative counterparts (38.8 vs 40.3, p = .007). This association was also confirmed in regression models adjusted for age, gender, and familial history of Alzheimer's disease (odds ratio = 0.94; 95% confidence interval 0.89-0.99; p = .02). This finding was consistent in cognitively normal individuals and in those with mild cognitive impairment, using the clinical dementia rating scale.

CONCLUSIONS

This study highlighted an association between early functional limitations and brain amyloid deposition in elderly subjects. These symptoms could be the clinical manifestations of amyloid plaques even in the absence of overt dementia. Further prospective studies are warranted for examining the evolution of ADL-PI score over the course of Alzheimer's disease.

An Analysis of the Public Financial Support Eligibility Rule for French Dependent Elders with Alzheimer's Disease

BACKGROUND

It is crucial to define health policies that target patients with the highest needs. In France, public financial support is provided to dependent patients: it can be used to finance informal care time and nonmedical care use. Eligibility for public subsidies and reimbursement of costs is associated with a specific tool: the autonomie gérontologie groupes iso-ressources (AGGIR) scale score.

OBJECTIVE

Our objective was to explore whether patients with Alzheimer's disease who are eligible for public financial support have greater needs than do noneligible patients.

METHODS

Using data from the Dépendance des patients atteints de la maladie d'Alzheimer en France study, we calculated nonmedical care expenditures (in €) using microcosting methods and informal care time demand (hours/month) using the Resource Use in Dementia questionnaire. We measured the burden associated with informal care provision with Zarit Burden Interview. We used a modified two-part model to explore the correlation between public financial support eligibility and these three variables.

RESULTS

We find evidence of higher informal care use, higher informal caregivers' burden, and higher care expenditures when patients have an AGGIR scale score corresponding to public financial support eligibility.

CONCLUSIONS

The AGGIR scale is useful to target patients with the highest costs and needs. Given our results, public subsidies could be used to further sustain informal caregivers networks by financing programs dedicated to lowering informal caregivers' burden.

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: 75.3 years; female: 64.8 %), enrolled by 13 memory clinics, were randomized into one of the following four groups: omega-3 supplementation alone, multidomain intervention alone, omega-3 plus multidomain intervention, or placebo. Participants underwent cognitive, functional and biological assessments at M6, M12, M24 and M36 visits. The primary endpoint is a change of memory function at 3 years, as assessed by the Free and Cued Selective Reminding test. All participants will be followed for 2 additional years after the 3-years intervention (MAPT PLUS extension study).

INTERVENTIONS

1/Omega-3 supplementation: two soft capsules daily as a single dose, containing a total of 400 mg docosahexaenoic acid (DHA), i.e., 800 mg docosahexaenoic acid per day, for 3 years. 2/ Multidomain intervention: collective training sessions conducted in small groups (6-8 participants) in twelve 120-minute sessions over the first 2 months (two sessions a week for the first month, and one session a week the second month) then a 60-minute session per month in the following three areas: nutrition, physical activity, and cognition until the end of the 3 years. In addition to the collective sessions, individualized preventive outpatient visits exploring possible risk factors for cognitive decline are performed at baseline, M12 and M24.

BASELINE POPULATION

For cognition, the mean MMSE at baseline was 28.1 (± 1.6). About 58% and 42% of participants had a CDR score equal to 0 and 0.5, respectively. Regarding mobility status, 200 (11.9%) had a 4-m gait speed lower or equal to 0.8 m/s. According to the Fried criteria, 673 (42.1%) participants were considered pre frail, and 51 (3.2%) frail. The red blood cell DHA content was 26.1 ± 8.1 µg/g. Five hundred and three participants underwent baseline MRI. AV45 PET scans were performed in 271 individuals and preliminary results showed that 38.0% had a cortical SUVR > 1.17, which gave an indication of significant brain amyloïd deposit. DISCUSSION: The MAPT trial is presently the first largest and longest multidomain preventive trial relevant to cognitive decline in older adults with subjective memory complaints. The multidomain intervention designed for the MAPT trial is likely to be easily implemented within the general population.

Effects of Gingko biloba supplementation in Alzheimer's disease patients receiving cholinesterase inhibitors: data from the ICTUS study

Ginkgo biloba (Gb) is currently the most investigated and adopted herbal remedy for cognitive disorders and Alzheimer's disease (AD). Nevertheless, its efficacy in the prevention and treatment of dementia still remains controversial. Specifically, the added effects of Gb in subjects already receiving "conventional" anti-dementia treatments have been to date very scarcely investigated. We evaluated whether the use of Gb is associated with additional cognitive and functional benefit in AD patients already in treatment with cholinesterase inhibitors (ChEIs). Data are from mild to moderate AD patients under ChEI treatment recruited in the Impact of Cholinergic Treatment USe (ICTUS) study. Mixed model analyses were performed to measure six-monthly modifications in the Mini Mental State Examination (MMSE), the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-Cog) subscale score, and the Activities of Daily Living (ADL) scale over a follow-up of 1 year according to the additional Gb supplementation. A total of 828 subjects were considered for the present analyses. Significantly different modifications at the MMSE score over the 12-month follow-up were reported between patients on combined therapy compared to those only taking ChEIs. On the contrary, the modification of the ADAS-Cog score between the two groups did not show statistically significant differences, although similar trends were noticed. No significant modifications of the two adopted outcome measures were observed at the mid-term 6-month evaluation. The modifications over time of the ADL score did not show statistically significant differences between the two groups of interest. Our findings suggest that Gb may provide some added cognitive benefits in AD patients already under ChEIs treatment. The clinical meaningfulness of such effects remains to be confirmed and clarified.

Long-term progression of Alzheimer's disease in patients under antidementia drugs

BACKGROUND

Patients with Alzheimer's disease (AD), even in the presence of symptomatic relief from medical intervention, face a persistent worsening of cognitive decline and performance in activities of daily living. Data regarding the long-term disease progression outside of therapeutic trials are lacking. We examined the effects of standard of care for AD patients on the prognosis of the disease in a real-life study over a 4-year period.

METHODS

A total of 686 patients with mild-moderate AD were enrolled in 16 memory clinics (REseau sur la maladie d' Alzheimer FRançais [REAL.FR] cohort) and followed up twice annually with tools used in therapeutic trials (Mini-Mental Status Examination, Alzheimer Disease Assessment Scale-cognitive subscale [ADAS-cog]: cognitive function, Clinical Dementia Rating: dementia severity, Activity of Daily Living [ADL]: incapacities, NeuroPsychiatric Inventory: neuropsychiatric symptom).

RESULTS

More than 90% of the patients used AD-specific medication over 4 years. Patients lost on average 2.4 points per year on the Mini-Mental Status Examination and gained 4.5 points on the ADAS-cog. ADL and NeuroPsychiatric Inventory scores became significantly worse over time. Incidence of incapacities for ADL and worsening of neuropsychiatric symptoms were 52.5 (95% confidence interval [CI]: 47.7-57.4) and 51.1 (95% CI: 46.2-56.1), respectively. Rates of mortality and institutionalization were 7.4 (95% CI: 6.2-8.5) and 13.4 (95% CI: 11.7-15.1). In all, 17% of patients in mild stage at baseline (Clinical Dementia Rating = 0.5) did not experience a major event (functional disabilities, neuropsychiatric symptoms, or death) over a 4-year period.

CONCLUSIONS

As compared with previous surveys, the current study shows slower rates of decline in AD patients. The present data also underline the high level of variability of disease progression among AD patients. Outcome measures commonly used in clinical trials will need to take into account the recent changes in the prognosis of the disease.

Differences in resource use and costs of dementia care between European countries: baseline data from the ICTUS study

OBJECTIVES

This study aimed to estimate the costs of formal and informal care of patients with Alzheimer's disease, to compare care costs across European countries and identify potential differences in cost patterns between countries and regions.

SETTING

The ICTUS study is a prospective, naturalistic observational study conducted in specialised memory clinics in 12 European countries. In total, 1385 patients diagnosed with Alzheimer's disease were enrolled at baseline. All subjects had a reliable informant (primary caregiver) and informed consent was obtained from patients or their primary caregiver.

MAIN OUTCOME MEASURES

Resource utilization data was captured with the RUD Lite (Resource Utilization in Dementia) instrument and caregiver burden with the Zarit Burden Interview (ZBI). Patient disease severity was measured with the Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-cog), Katz´ index (PADL), Instrumental activities of daily living (IADL) scale and Neuropsychiatric inventory (NPI).

RESULTS

The mean annual cost of care per patient was estimated to €7,820 (95% CI: €7,194-€8,446), whereof 54% were costs of informal care, 16% direct medical costs and 30% community care costs. There were substantial differences in total resource utilization and also in the balance between formal and informal care between Northern, Western and Southern Europe. PADL scores were strongly associated with formal care costs while IADL scores correlated strongly with informal care costs.

CONCLUSIONS

Costs of Alzheimer's disease are high across European countries. Activities of daily living is an important determinant of care costs. Formal care service use is lower and informal care higher in Southern Europe compared to Western and Northern Europe. Differences in resource utilization patterns are important to consider in international studies of dementia care costs as well as in economic evaluations of new treatments for dementia.

Gait and balance impairments in Alzheimer disease patients

OBJECTIVE

To describe the characteristics and associated factors of Alzheimer disease (AD) patients with balance and gait impairments.

METHODS

Balance and gait impairments were assessed in 380 AD patients using the Tinetti test.

RESULTS

A total of 120 (31.5%) patients had an abnormal Tinetti test, 96 (25.2%) had balance impairments, and 72 (18.9%) patients presented gait impairments. Global Tinetti score was associated with age [odds ratio (OR), 1.09; 95% confidence interval (CI), 1.05-1.14], Mini-Mental State Examination (MMSE) score (OR, 0.94; 95% CI, 0.90-0.99), activities of daily living (ADL) score (OR, 0.62; 95% CI, 0.47-0.83), and being man (OR, 0.44; 95% CI, 0.25-0.78). Balance impairment was associated with age (OR, 1.11; 95% CI, 1.05-1.17), ADL score (OR, 0.60; 95% CI, 0.43-0.84), and being female (OR, 0.19; 95% CI, 0.08-0.49). Gait impairment was associated with age (OR, 1.09; 95% CI, 1.03-1.15), MMSE score (OR, 0.92; 95% CI, 0.87-0.98), ADL score (OR, 0.63; 95% CI, 0.46-0.87), body mass index (OR, 1.10; 95% CI, 1.01-1.18), presence of comorbidities (OR, 2.13; 95% CI, 1.14-3.96), and the Cornell score (OR, 2.97; 95% CI, 1.12-7.89).

CONCLUSIONS

AD patients are frequently concerned with balance and gait impairments. These impairments were associated to factors related to the severity of the disease (low MMSE and low ADL); nonmodifiable factors such as age or sex; and modifiable factors such as depression, obesity, and presence of comorbidities.

Predictive factors of discontinuation and switch of cholinesterase inhibitors in community-dwelling patients with Alzheimer's disease: a 2-year prospective, multicentre, cohort study

BACKGROUND

The efficacy of cholinesterase inhibitors (ChEIs), especially over the long term, is still under discussion. There is a lack of data concerning the optimal drug treatment duration and the reasons for discontinuation, particularly outside the clinical trial setting.

OBJECTIVE

To identify predictive factors of discontinuation and switch of ChEIs in a real-world setting.

METHODS

A multicentre cohort study of 686 patients with mild-to-moderate ambulatory Alzheimer's disease who were diagnosed in 16 Alzheimer's disease expert centres in 2000-2 and who were assessed twice yearly for 2 years. The main outcome measure was ChEI discontinuation and switch (analysed using Cox survival analyses).

RESULTS

After 2 years, of the 611 subjects treated with a ChEI at baseline, 100 subjects had switched or discontinued ChEI therapy (incidence rate 12.7 [95% CI 10.2, 15.2] per 100 person-years). The incidences of switching and discontinuation were 9.2 (95% CI 7.0, 11.3) and 3.6 (95% CI 2.3, 4.8) per 100 person-years, respectively. In the multivariate analysis, predictive factors for switching were an ineffective ChEI dose (adjusted hazard ratio [HR(a)] = 6.91, 95% CI 3.08, 15.49), rapid cognitive decline (HR(a) = 4.10, 95% CI 1.85, 9.05), hospitalization unrelated to Alzheimer's disease (HR(a) = 2.33, 95% CI 1.07, 5.09) and anxiety (HR(a) = 2.08, 95% CI 1.16, 3.73). Predictive factors of discontinuation were: hospitalization related (HR(a) = 9.14, 95% CI 2.69, 31.07) or unrelated (HR(a) = 4.23, 95% CI 1.54, 11.59) to Alzheimer's disease, use of an anticholinergic drug (HR(a) = 4.26, 95% CI 1.46, 12.45) and weight loss (HR(a) = 3.77, 95% CI 1.15, 12.33).

CONCLUSIONS

This study highlights four types of predictors of switch or discontinuation, reflecting disease progression, reconsideration of ChEI benefits, adverse drug reactions to ChEIs and inappropriate concurrent use of anticholinergic drugs. Attention should be paid to anticholinergic agents and prescribers should be given better information about these drugs.

Spared and impaired abilities in community-dwelling patients entering the severe stage of Alzheimer's disease

BACKGROUND

Comprehensive geriatric assessments of patients entering the severe stage of Alzheimer's disease (AD) are scarce.

METHODS

Cross-sectional study of 126 patients entering the severe stage of AD in the longitudinal study of REAL.FR cohort. Patients who had a first MMSE score <10 during follow-up underwent cognitive, behavioral, nutritional and functional assessment. Support requirements were also evaluated.

RESULTS

The best-preserved cognitive abilities were social interaction and response to own name, while praxis, orientation, memory and language showed the largest declines. Regarding independence in daily living, locomotion was best preserved (71% of patients independent) while personal hygiene deteriorated most (15.5%). Behavioral disorders were frequent, and consisted principally of apathy, aberrant motor behavior, and agitation. The Mini Nutritional Assessment showed that 68.5% of patients were malnourished or at risk of malnutrition. Caregiver burden remained mild to moderate in 69.8% of cases. In addition, 80% of patients still lived at home and 71.6% used at least 2 support services, consisting mainly of physician visits and home help.

CONCLUSION

Assessment of remaining cognitive, functional abilities and behavioral disorders at entry to severe AD should help to improve targeted management aimed at preserving these abilities and treating complications, thereby optimizing these patients' quality of life.

Mild Alzheimer's disease: a "position paper"

Under the auspices of the Societe Francaise de Geriatrie et Gerontologie, a multi-disciplinary group of specialists in geriatrics, neurology, epidemiology, psychiatry, neuroradiology and nuclear medicine met with the aim of drawing up references on the methods for diagnosing and treating mild Alzheimer's disease. The critical analysis of international literature, conducted by Professor Bruno Vellas for the scientific committee, has served to support study of the latest knowledge in 2008. The multi-disciplinary group met on 14 and 15 May 2008 in order to set out the questions that this study must answer and to allocate draft studies. Thus, it has been possible to conduct a study focused on mild Alzheimer's disease, giving particular attention to diagnostic procedure, specific methods of treatment and the benefits of making a diagnosis.

Predictive value of rapid decline in mini mental state examination in clinical practice for prognosis in Alzheimer's disease

BACKGROUND

Given the poorer prognosis of Alzheimer's disease (AD) patients with rapid cognitive decline (RCD), there is a need for a clinical assessment tool to detect these patients.

OBJECTIVE

To investigate if there is a Mini Mental State Examination (MMSE) threshold of decline during 6 months of follow-up which predicts a worse disease progression at the 2-year follow-up. Then, to propose a feasible definition of RCD for routine clinical practice.

METHODS

Data from 565 community-dwelling AD patients recruited in a multi-centre prospective observational study were assessed. All patients had MMSE scores between 10 and 26 at inclusion and were followed up 6-monthly using a standardised clinical assessment. Patients were classified as rapid and non-rapid decliners according to 2 MMSE decline thresholds tested: >or=3 points and >or=4 points for decline over the first 6 months of the study. Worse disease outcome was defined as attainment of 1 of 4 clinical end points 18 months later: institutionalisation, death, increased physical dependence or worsening of behavioural and psychological symptoms.

RESULTS

135 patients (23.9%) lost >or=3 points during the first 6 months of follow-up in the MMSE score and 77 patients (13.6%) lost >or=4 points. Patients with moderate disease and a loss of >or=4 points showed a significantly increased risk of mortality (HR = 5.6, 95% CI 2.0-15.9) and institutionalisation (HR = 3.8, 95% CI 1.8-8.1) at the 2-year follow-up. The same MMSE threshold was associated with a higher risk of physical decline (HR = 1.6, 95% CI 1.2-2.3).

CONCLUSION

The loss of >or=4 points in MMSE during the first 6 months of follow-up seems to be a predictor of worse clinical course, and thus it could be used to define the category of AD patients presenting a RCD.

GuidAge study: a 5-year double blind, randomised trial of EGb 761 for the prevention of Alzheimer's disease in elderly subjects with memory complaints. i. rationale, design and baseline data

Primary and secondary prevention strategies for Alzheimer's disease (AD) are urgently needed. We have initiated a five-year prospective prevention study involving patients spontaneously reporting memory complaints. The primary objective is to determine the effect of treatment with EGb 76 on the rate of conversion from memory complaints to AD using survival analysis. Ambulatory patients aged at least 70 years who spontaneously reported a memory complaint during a GP or memory centre consultation were eligible for inclusion. Patients with major objective memory impairment or clinically relevant symptoms of anxiety and depression were excluded. Subjects were randomised to receive either EGb 761 120mg bid or matching placebo. Participants undergo an annual visit at a memory centre, where a series of neuropsychological tests are administered to assess cognitive function (Grober and Buschke, Trail-Making and controlled oral word association tests) and cognitive status (MMS and CDR). Functional status is evaluated with the Instrumental Activities of Daily Living questionnaire. The primary outcome is the transition to a diagnosis of AD (DSM-IV and NINCDS-ADRDA criteria), determined at the annual memory centre visit. A total of 4066 patients were screened for participation, of whom 2854 fulfilled the eligibility criteria and were entered into the study. Their mean age was 76.8+/-4.4 years and 66.7% were female. The mean MMSE score was 27.8+/-1.7 and 55.5% presented a CDR score of 0.5. This study will enable us to evaluate the efficacy of EGb761 in the prevention of AD, and to assess the usefulness of various baseline characteristics as predictors of conversion to AD in this population.

Prevention of progression to dementia in the elderly: rationale and proposal for a health-promoting memory consultation (an IANA Task Force)

Alzheimer's disease (AD) is the most frequent form of dementia and according to the most recent estimation it affects nearly 27 million people in the world. The onset of the disease is generally insidious. It is becoming increasingly evident that the underlying pathophysiological mechanisms are active long before the appearance of the clinical symptoms of the disease. In the current context, it is important to develop strategies to delay the onset of cognitive decline. Delaying the onset by 5 years would reduce the prevalence by half at term, and a delay of 10 years would reduce it by three-quarters. The effectiveness of currently suggested preventive approaches remains to be confirmed, but certain strategies could be applied straight away to at-risk subjects. We propose that a health-promoting memory consultation should be set up for elderly persons who have attended a specialized memory consultation and in whom the diagnosis of dementia and of AD in particular, has not been established by standardized tools. Through this consultation, they would be offered full multidimensional investigation of all aspects of their health status, follow-up could be organized, general practitioners in private practice could be made more conscious of this population and the elderly could be made more aware of the risk factors to which they are exposed. The development of an information policy for the elderly would meet a present need. In our reflection, we must take into account the question of how to give this preventive consultation its due place in the healthcare pathway of the elderly person in order to ensure coordinated follow-up with all the other health professionals involved. The principle of the health-promoting memory consultation is undergoing validation in a large French multicentre preventive trial in 1200 frail elderly persons aged 70 years followed for three years, the Multidomain Alzheimer Preventive Trial (MAPT).

Prognosis of Alzheimer's disease today: a two-year prospective study in 686 patients from the REAL-FR Study

BACKGROUND

The aim of the present study was to describe the long-term evolution of Alzheimer's disease (AD) in a prospective cohort of patients under treatment with a close follow-up.

METHODS

Six hundred eighty-six AD patients from the French Network on AD (REAL-FR) were followed up and assessed every 6 months for 2 years. Cognitive, functional, behavioral, nutritional, and global status were evaluated by using Mini-Mental State Examination (MMSE), cognitive subscale of AD Assessment Scale (ADAS-cog), Activities of Daily Living scale (ADL), Neuropsychiatric Inventory (NPI), Mini-Nutritional Assessment (MNA), and Clinical Dementia Rating (CDR).

RESULTS

There were 85.13% of patients who were specifically treated for AD during their participation in the study. We observed significant changes (P < .0001) on MMSE, -4.57 +/- 0.23; ADAS-cog, 7.11 +/- 0.41; ADL, -1.32 +/- 0.07; NPI, 2.94 +/- 0.77; MNA, -0.81 +/- 0.17; and sum of boxes of the CDR (CDR-SB), 4.17 +/- 0.17. After 2 years, 10.79% (95% confidence interval [CI], 8.47 to 13.11) of the patients evolved twice as rapidly as the mean of the whole cohort on MMSE (loss, > or =9 points), 65.89% (95% CI, 62.34 to 69.44) reported a loss of 3 to 9 points, and 23.32% (95% CI, 20.16 to 26.46) were stable or improved (loss of -2 points maximum). Annual incidences for institutionalization, hospitalization, and death were 11.84% (95% CI, 9.76 to 13.92), 26.13% (95% CI, 22.52 to 29.74), and 5.95% (95% CI, 4.56 to 7.34), respectively.

CONCLUSIONS

In a recent large AD cohort mostly under treatment, AD evolution appeared to be variable, with high incidences for death or institutionalization and with 11.84% of the patients exhibiting a rapid cognitive decline, whereas one fourth of the cohort appeared in relatively stable condition, and two thirds had a moderate but significant evolution of the disease. More studies are needed to better understand these variations in patients' evolution.

Memory complaints to the general practitioner: data from the GuidAge study

Memory complaints are relatively common in elderly people, although they are not always reported to the general practitioner (GP). These subjective complaints do not necessarily correlate with objective measures of memory impairment or cognitive performance, but they may be an early indication of impairment at a state that is undetectable by standard testing instruments. Memory complaints may also predict future cognitive decline. The GuidAge study is a secondary prevention trial for Alzheimer's disease involving non-demented individuals aged 70 years or older having spontaneously complained of memory problems to their GP. More than half of participants had a Clinical Dementia Rating score of 0.5 at baseline. The percentage of participants reporting problems on the McNair and Kahn scale varied from 6.2% to 78.6% per item. Certain specific memory complaints may be more related than others to the beginning of the neurodegenerative process, and could predict future cognitive decline. The importance of memory complaints should not be underestimated in clinical practice.

The ICTUS Study: A Prospective Longitudinal Observational Study of 1,380 AD Patients in Europe

The long-term objective of the ICTUS study is to identify milestones in Alzheimer's disease (AD) progression and to develop a model to predict disease course in individual AD patients in Europe. The secondary objectives are to describe the patterns of prescribing, and the socioeconomic impact of AD in Europe. Between 2003 and 2005 1,380 patients with probable AD were recruited in specialised (secondary care) clinics in 12 European countries. Their mean age was 76 years and they had a mean of 8.0 +/- (SD) 4.6 years of education. Thirty-five percent were male. The mean MMSE score was 20.4 +/- (SD) 4.0. Forty-three percent had very mild dementia (CDR 0.5) and 44% had mild dementia (CDR 1). All patients completed baseline evaluation and biannual follow-up is ongoing. The goals of the current study are to describe the specific methods for recruitment in this crosscultural setting and the characteristics of the inception ICTUS cohort, including clinical features, co-morbidity, neuropsychological performance, neuropsychiatric symptoms, functional impairment and social burden.