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1.
Aging Clin Exp Res ; 34(12): 3115-3121, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36242723

ABSTRACT

BACKGROUND: Research involving multimorbid older patients is gaining momentum. However, little is known about how to plan a randomised controlled trial (RCT) involving this group of patients. An evidence-based approach to the challenges of a recruitment process could guide researchers and help prevent underpowered trials. AIM: To define the number of multimorbid older patients that need to be identified and the number of eligible patients that need to be invited to achieve the desired recruitment number to a RCT. METHOD: We used recruitment data from the GerMoT trial, a RCT comparing proactive outpatient care based on Comprehensive Geriatric Assessment with usual care. Multimorbid older patients with high healthcare utilisation were recruited to the trial. RESULTS: Of the 1212 patients identified in a database as meeting the inclusion criteria 838 (70%) could be invited to participate in the trial. The rest could not be invited for a variety of reasons; 162 had moved out of area or into nursing homes and 86 had died before they could be contacted. 113 could not be reached. 450 (54%) of the invited patients agreed to participate. CONCLUSIONS: In our study, we have shown that it is possible to achieve a good consent rate despite older participants with multimorbidity. This can be used when planning an RCT for this patient group, who are often excluded from clinical trials. Our results are specific to a context that provides similar abilities to identify and recruit patients as can be seen in Sweden.


Subject(s)
Multimorbidity , Nursing Homes , Humans , Aged , Geriatric Assessment , Databases, Factual , Hospitals
2.
Lancet Neurol ; 18(11): 1034-1044, 2019 11.
Article in English | MEDLINE | ID: mdl-31526625

ABSTRACT

BACKGROUND: Biomarker-based risk predictions of dementia in people with mild cognitive impairment are highly relevant for care planning and to select patients for treatment when disease-modifying drugs become available. We aimed to establish robust prediction models of disease progression in people at risk of dementia. METHODS: In this modelling study, we included people with mild cognitive impairment (MCI) from single-centre and multicentre cohorts in Europe and North America: the European Medical Information Framework for Alzheimer's Disease (EMIF-AD; n=883), Alzheimer's Disease Neuroimaging Initiative (ADNI; n=829), Amsterdam Dementia Cohort (ADC; n=666), and the Swedish BioFINDER study (n=233). Inclusion criteria were a baseline diagnosis of MCI, at least 6 months of follow-up, and availability of a baseline Mini-Mental State Examination (MMSE) and MRI or CSF biomarker assessment. The primary endpoint was clinical progression to any type of dementia. We evaluated performance of previously developed risk prediction models-a demographics model, a hippocampal volume model, and a CSF biomarkers model-by evaluating them across cohorts, incorporating different biomarker measurement methods, and determining prognostic performance with Harrell's C statistic. We then updated the models by re-estimating parameters with and without centre-specific effects and evaluated model calibration by comparing observed and expected survival. Finally, we constructed a model combining markers for amyloid deposition, tauopathy, and neurodegeneration (ATN), in accordance with the National Institute on Aging and Alzheimer's Association research framework. FINDINGS: We included all 2611 individuals with MCI in the four cohorts, 1007 (39%) of whom progressed to dementia. The validated demographics model (Harrell's C 0·62, 95% CI 0·59-0·65), validated hippocampal volume model (0·67, 0·62-0·72), and updated CSF biomarkers model (0·72, 0·68-0·74) had adequate prognostic performance across cohorts and were well calibrated. The newly constructed ATN model had the highest performance (0·74, 0·71-0·76). INTERPRETATION: We generated risk models that are robust across cohorts, which adds to their potential clinical applicability. The models could aid clinicians in the interpretation of CSF biomarker and hippocampal volume results in individuals with MCI, and help research and clinical settings to prepare for a future of precision medicine in Alzheimer's disease. Future research should focus on the clinical utility of the models, particularly if their use affects participants' understanding, emotional wellbeing, and behaviour. FUNDING: ZonMW-Memorabel.


Subject(s)
Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Cognitive Dysfunction/cerebrospinal fluid , Hippocampus/pathology , Magnetic Resonance Imaging , Peptide Fragments/cerebrospinal fluid , Proportional Hazards Models , tau Proteins/cerebrospinal fluid , Aged , Aged, 80 and over , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/epidemiology , Alzheimer Disease/pathology , Cognitive Dysfunction/pathology , Disease Progression , Europe/epidemiology , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Multicenter Studies as Topic/statistics & numerical data , Nerve Degeneration , Neuroimaging , North America/epidemiology , Organ Size , Phosphorylation , Prognosis , Protein Processing, Post-Translational , tau Proteins/chemistry
3.
Alzheimers Dement ; 15(7): 888-898, 2019 07.
Article in English | MEDLINE | ID: mdl-31164314

ABSTRACT

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.


Subject(s)
Alzheimer Disease , Amyloid , Apolipoprotein E4/genetics , Cognitive Dysfunction/pathology , Disease Progression , Prodromal Symptoms , Aged , Alleles , Alzheimer Disease/genetics , Alzheimer Disease/pathology , Biomarkers/cerebrospinal fluid , Female , Genotype , Humans , Longitudinal Studies , Male , Positron-Emission Tomography , Sex Factors , Time Factors , tau Proteins/cerebrospinal fluid
4.
Alzheimers Res Ther ; 10(1): 56, 2018 06 20.
Article in English | MEDLINE | ID: mdl-29925412

ABSTRACT

Upon publication of this article [1], it was noticed that there were some inconsistencies in Tables 1, 2 and 3. Some of the superscript letters were incorrectly assigned. Please see below the correct tables.

5.
Alzheimers Res Ther ; 9(1): 101, 2017 12 29.
Article in English | MEDLINE | ID: mdl-29284531

ABSTRACT

BACKGROUND: Cerebrovascular disease (CVD) and amyloid-ß (Aß) often coexist, but their influence on neurodegeneration and cognition in predementia stages remains unclear. We investigated the association between CVD and Aß on neurodegenerative markers and cognition in patients without dementia. METHODS: We included 271 memory clinic patients with subjective or objective cognitive deficits but without dementia from the BioBank Alzheimer Center Limburg cohort (n = 99) and the LeARN (n = 50) and DESCRIPA (n = 122) multicenter studies. CSF Aß1-42 and white matter hyperintensities (WMH) on magnetic resonance imaging (MRI) scans were used as measures of Aß and CVD, respectively. Individuals were classified into four groups based on the presence (+) or absence (-) of Aß and WMH. We investigated differences in phosphorylated tau, total tau (t-tau), and medial temporal lobe atrophy (MTA) between groups using general linear models. We examined cognitive decline and progression to dementia using linear mixed models and Cox proportional hazards models. All analyses were adjusted for study and demographics. RESULTS: MTA and t-tau were elevated in the Aß - WMH+, Aß + WMH-, and Aß + WMH+ groups. MTA was most severe in the Aß + WMH+ group compared with the groups with a single pathology. Both WMH and Aß were associated with cognitive decline, but having both pathologies simultaneously was not associated with faster decline. CONCLUSIONS: In the present study, we found an additive association of Aß and CVD pathology with baseline MTA but not with cognitive decline. Because our findings may have implications for diagnosis and prognosis of memory clinic patients and for future scientific research, they should be validated in a larger sample with longer follow-up.


Subject(s)
Amyloid beta-Peptides/metabolism , Brain/diagnostic imaging , Cerebrovascular Disorders/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Dementia/diagnostic imaging , Aged , Apolipoproteins E/genetics , Atrophy , Biomarkers/cerebrospinal fluid , Brain/metabolism , Cerebrovascular Disorders/genetics , Cerebrovascular Disorders/metabolism , Cognitive Dysfunction/genetics , Cognitive Dysfunction/metabolism , Cohort Studies , Dementia/genetics , Dementia/metabolism , Disease Progression , Female , Humans , Magnetic Resonance Imaging , Male , Mental Status and Dementia Tests , Middle Aged , Phosphorylation , tau Proteins/metabolism
6.
J Alzheimers Dis ; 60(4): 1387-1395, 2017.
Article in English | MEDLINE | ID: mdl-29036813

ABSTRACT

BACKGROUND: Lifestyle factors have been associated with the risk of dementia, but the association with Alzheimer's disease (AD) remains unclear. OBJECTIVE: To examine the association between later life lifestyle factors and AD biomarkers (i.e., amyloid-ß 1-42 (Aß42) and tau in cerebrospinal fluid (CSF), and hippocampal volume) in individuals with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). In addition, to examine the effect of later life lifestyle factors on developing AD-type dementia in individuals with MCI. METHODS: We selected individuals with SCD (n = 111) and MCI (n = 353) from the DESCRIPA and Kuopio Longitudinal MCI studies. CSF Aß42 and tau concentrations were assessed with ELISA assay and hippocampal volume with multi-atlas segmentation. Lifestyle was assessed by clinical interview at baseline for: social activity, physical activity, cognitive activity, smoking, alcohol consumption, and sleep. We performed logistic and Cox regression analyses adjusted for study site, age, gender, education, and diagnosis. Prediction for AD-type dementia was performed in individuals with MCI only. RESULTS: Later life lifestyle factors were not associated with AD biomarkers or with conversion to AD-type dementia. AD biomarkers were strongly associated with conversion to AD-type dementia, but these relations were not modulated by lifestyle factors. Apolipoprotein E (APOE) genotype did not influence the results. CONCLUSIONS: Later life lifestyle factors had no impact on key AD biomarkers in individuals with SCD and MCI or on conversion to AD-type dementia in MCI.


Subject(s)
Cognition Disorders/cerebrospinal fluid , Cognition Disorders/diagnostic imaging , Hippocampus/diagnostic imaging , Life Style , Age Factors , Aged , Alcohol Drinking/cerebrospinal fluid , Alcohol Drinking/epidemiology , Alcohol Drinking/pathology , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/epidemiology , Alzheimer Disease/pathology , Apolipoproteins E/genetics , Cognition , Cognition Disorders/epidemiology , Cognition Disorders/pathology , Diagnostic Self Evaluation , Disease Progression , Educational Status , Exercise , Female , Follow-Up Studies , Hippocampus/pathology , Humans , Longitudinal Studies , Male , Organ Size , Sex Factors , Sleep , Smoking/cerebrospinal fluid , Smoking/epidemiology , Smoking/pathology , Social Behavior
7.
Alzheimers Res Ther ; 9(1): 70, 2017 Aug 31.
Article in English | MEDLINE | ID: mdl-28859660

ABSTRACT

BACKGROUND: Whether age at onset influences Alzheimer's disease (AD) progression and the effectiveness of cholinesterase inhibitor (ChEI) therapy is not clear. We aimed to compare longitudinal cognitive and global outcomes in ChEI-treated patients with early-onset Alzheimer's disease (EOAD) versus late-onset Alzheimer's disease (LOAD) in clinical practice. METHODS: This 3-year, prospective, observational, multicentre study included 1017 participants with mild to moderate AD; 143 had EOAD (age at onset < 65 years) and 874 had LOAD (age at onset ≥ 65 years). At baseline and semi-annually, patients were assessed using cognitive, global and activities of daily living (ADL) scales, and the dose of ChEI was recorded. Potential predictors of decline were analysed using mixed-effects models. RESULTS: Six-month response to ChEI therapy and long-term prognosis in cognitive and global performance were similar between the age-at-onset groups. However, deterioration was significantly faster when using the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) over 3 years in participants with EOAD than in those with LOAD; hence, prediction models for the mean ADAS-Cog trajectories are presented. The younger cohort had a larger proportion of homozygote apolipoprotein E (APOE) ε4 allele carriers than the older cohort; however, APOE genotype was not a significant predictor of cognitive impairment in the multivariate models. A slower rate of cognitive progression was related to initiation of ChEIs at an earlier stage of AD, higher ChEI dose and fewer years of education in both groups. In LOAD, male sex, better instrumental ADL ability and no antipsychotic drug use were additional protective characteristics. The older patients received a lower ChEI dose than the younger individuals during most of the study period. CONCLUSIONS: Although the participants with EOAD showed a faster decline in ADAS-Cog, had a longer duration of AD before diagnosis, and had a higher frequency of two APOE ε4 alleles than those with LOAD, the cognitive and global responses to ChEI treatment and the longitudinal outcomes after 3 years were similar between the age-at-onset groups. A higher mean dose of ChEI and better cognitive status at the start of therapy were independent protective factors in both groups, stressing the importance of early treatment in adequate doses for all patients with AD.


Subject(s)
Activities of Daily Living/psychology , Alzheimer Disease , Cholinesterase Inhibitors/therapeutic use , Cognition Disorders/etiology , Age of Onset , Aged , Aged, 80 and over , Alzheimer Disease/complications , Alzheimer Disease/drug therapy , Alzheimer Disease/psychology , Apolipoproteins E/genetics , Female , Humans , Longitudinal Studies , Male , Mental Status Schedule , Middle Aged , Neuropsychological Tests , Outcome Assessment, Health Care , Time Factors
8.
Dement Geriatr Cogn Dis Extra ; 7(1): 172-187, 2017.
Article in English | MEDLINE | ID: mdl-28626471

ABSTRACT

BACKGROUND/AIMS: Whether age at onset influences functional deterioration in Alzheimer disease (AD) is unclear. We, therefore, investigated risk factors for progression in activities of daily living (ADL) and nursing home placement (NHP) in cholinesterase inhibitor (ChEI)-treated patients with early-onset AD (EOAD) versus late-onset AD (LOAD). METHODS: This 3-year, prospective, observational, multicenter study included 1,017 participants with mild-to-moderate AD; 143 had EOAD (onset <65 years) and 874 LOAD (onset ≥65 years). Possible sociodemographic and clinical factors that could affect functional outcome and NHP were analyzed using mixed-effects models and logistic regression, respectively. RESULTS: Younger individuals exhibited longer illness duration before AD diagnosis, whereas 6-month functional response to ChEI therapy, 3-year changes in ADL capacities, time from diagnosis to NHP, and survival time in nursing homes were similar between the groups. In LOAD, a higher ChEI dose, no antidepressant use, and lower education level were protective factors for slower instrumental ADL (IADL) decline. In EOAD, antihypertensives/cardiac therapy implied faster IADL progression but lower risk of NHP. CONCLUSION: This study highlights the clinical importance of an earlier diagnosis and treatment initiation and the need for functional evaluations in EOAD. Despite the age differences between EOAD and LOAD, a similar need for nursing homes was observed.

9.
Neurobiol Aging ; 56: 33-40, 2017 08.
Article in English | MEDLINE | ID: mdl-28482212

ABSTRACT

We investigated whether dementia risk factors were associated with prodromal Alzheimer's disease (AD) according to the International Working Group-2 and National Institute of Aging-Alzheimer's Association criteria, and with cognitive decline. A total of 1394 subjects with mild cognitive impairment from 14 different studies were classified according to these research criteria, based on cognitive performance and biomarkers. We compared the frequency of 10 risk factors between the subgroups, and used Cox-regression to examine the effect of risk factors on cognitive decline. Depression, obesity, and hypercholesterolemia occurred more often in individuals with low-AD-likelihood, compared with those with a high-AD-likelihood. Only alcohol use increased the risk of cognitive decline, regardless of AD pathology. These results suggest that traditional risk factors for AD are not associated with prodromal AD or with progression to dementia, among subjects with mild cognitive impairment. Future studies should validate these findings and determine whether risk factors might be of influence at an earlier stage (i.e., preclinical) of AD.


Subject(s)
Alzheimer Disease/etiology , Aged , Alcohol Drinking/adverse effects , Biomarkers , Cognition , Cognitive Dysfunction/etiology , Depression , Disease Progression , Female , Humans , Hypercholesterolemia , Male , Middle Aged , Obesity , Proportional Hazards Models , Risk Factors
10.
Alzheimers Dement ; 13(8): 903-912, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28216393

ABSTRACT

INTRODUCTION: We aimed to determine the added value of cerebrospinal fluid (CSF) to clinical and imaging tests to predict progression from mild cognitive impairment (MCI) to any type of dementia. METHODS: The risk of progression to dementia was estimated using two logistic regression models based on 250 MCI participants: the first included standard clinical measures (demographic, clinical, and imaging test information) without CSF biomarkers, and the second included standard clinical measures with CSF biomarkers. RESULTS: Adding CSF improved predictive accuracy with 0.11 (scale from 0-1). Of all participants, 136 (54%) had a change in risk score of 0.10 or higher (which was considered clinically relevant), of whom in 101, it was in agreement with their dementia status at follow-up. DISCUSSION: An individual person's risk of progression from MCI to dementia can be improved by relying on CSF biomarkers in addition to recommended clinical and imaging tests for usual care.


Subject(s)
Cognitive Dysfunction/cerebrospinal fluid , Dementia/cerebrospinal fluid , Aged , Aged, 80 and over , Biomarkers/cerebrospinal fluid , Cognitive Dysfunction/diagnostic imaging , Dementia/diagnostic imaging , Disease Progression , Educational Status , Female , Follow-Up Studies , Humans , Logistic Models , Magnetic Resonance Imaging , Male , Mental Status and Dementia Tests , Middle Aged , Prognosis , Risk Assessment , Temporal Lobe/diagnostic imaging
11.
J Alzheimers Dis ; 56(2): 543-555, 2017.
Article in English | MEDLINE | ID: mdl-28059783

ABSTRACT

Cerebrospinal fluid (CSF) biomarkers may support the diagnosis of Alzheimer's disease (AD). We studied if the diagnostic power of AD CSF biomarker concentrations, i.e., Aß42, total tau (t-tau), and phosphorylated tau (p-tau), is affected by differences in lateral ventricular volume (VV), using CSF biomarker data and magnetic resonance imaging (MRI) scans of 730 subjects, from 13 European Memory Clinics. We developed a Matlab-algorithm for standardized automated segmentation analysis of T1 weighted MRI scans in SPM8 for determining VV, and computed its ratio with total intracranial volume (TIV) as proxy for total CSF volume. The diagnostic power of CSF biomarkers (and their combination), either corrected for VV/TIV ratio or not, was determined by ROC analysis. CSF Aß42 levels inversely correlated to VV/TIV in the whole study population (Aß42: r = -0.28; p < 0.0001). For CSF t-tau and p-tau, this association only reached statistical significance in the combined MCI and AD group (t-tau: r = -0.15; p-tau: r = -0.13; both p < 0.01). Correction for differences in VV/TIV improved the differentiation of AD versus controls based on CSF Aß42 alone (AUC: 0.75 versus 0.81) or in combination with t-tau (AUC: 0.81 versus 0.91). In conclusion, differences in VV may be an important confounder in interpreting CSF Aß42 levels.


Subject(s)
Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/diagnostic imaging , Cerebral Ventricles/diagnostic imaging , Cognitive Dysfunction/cerebrospinal fluid , Cognitive Dysfunction/diagnostic imaging , Aged , Algorithms , Amyloid beta-Peptides/cerebrospinal fluid , Area Under Curve , Atrophy , Biomarkers/cerebrospinal fluid , Female , Hippocampus/diagnostic imaging , Humans , Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Organ Size , Pattern Recognition, Automated , Peptide Fragments/cerebrospinal fluid , ROC Curve , tau Proteins/cerebrospinal fluid
12.
Alzheimers Res Ther ; 8: 7, 2016 Feb 17.
Article in English | MEDLINE | ID: mdl-26883213

ABSTRACT

BACKGROUND: There is an increasing interest in cognitive and functional outcomes in the respective stages of Alzheimer's disease (AD) and in novel therapies particularly for the milder phases of AD. Our aim was to describe and compare various aspects of disease progression in patients with mild versus moderate AD in routine clinical practice of cholinesterase inhibitor (ChEI) therapy. METHODS: This 3-year, prospective, observational, multicentre study included 1021 participants. Of these, 734 had mild AD (Mini-Mental State Examination (MMSE) score, 20-26) and 287 had moderate AD (MMSE score, 10-19) at the start of ChEI treatment. At baseline and every 6 months, patients were assessed using cognitive, global, instrumental and basic activities of daily living (ADL) scales. Potential predictors of deterioration in moderate AD were analysed using mixed-effects models. RESULTS: The change from baseline between participants with mild and moderate stages of AD after 3 years of ChEI therapy differed significantly on the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and basic ADL, but not using the MMSE and instrumental ADL scales. Protective independent factors for better cognitive long-term outcome in the group with moderate AD were older age, higher instrumental ADL ability, no antipsychotics, usage of non-steroidal anti-inflammatory drugs/acetylsalicylic acid, living with family member, lower education and a higher mean dose of ChEI. Apolipoprotein E genotype did not influence the rates of disease progression or the longitudinal outcomes. Prediction models were provided for moderate AD. CONCLUSIONS: More sensitive cognitive measures, such as the ADAS-cog scale, are required to detect a possibly faster deterioration among the participants with moderate AD. This study highlighted the clinical importance of instrumental ADL evaluations in patients at a mild stage of AD, and the importance of optimizing the ChEI dose even for individuals with moderate AD. Solitary living was a risk factor for faster cognitive decline, and probably expanded the need for formal care in the group with moderate AD. The patients with more advanced AD and presumably more pronounced neuroinflammation might have additional cognitive benefits from longer-term treatment with anti-inflammatory drugs.


Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/psychology , Cholinesterase Inhibitors/therapeutic use , Cognition/drug effects , Activities of Daily Living , Aged , Aged, 80 and over , Donepezil , Female , Galantamine/therapeutic use , Humans , Indans/therapeutic use , Male , Mental Status Schedule , Piperidines/therapeutic use , Prospective Studies , Rivastigmine/therapeutic use , Severity of Illness Index , Treatment Outcome
13.
Epigenomics ; 7(4): 533-7, 2015.
Article in English | MEDLINE | ID: mdl-26111027

ABSTRACT

Epigenetic dysregulation has been associated with cognitive decline and Alzheimer's disease. The present study investigated associations between common SNPs in genes regulating DNA methylation and age-related changes in cognitive decline in two independent prospective cohorts of patients suffering from mild cognitive impairment. An association between the rs1187120 SNP in DNMT3A and annual decline in cognitive functioning was discovered and replicated, suggesting that DNMT3A moderates cognitive decline in subjects with mild cognitive impairment.


Subject(s)
Cognitive Dysfunction/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , Polymorphism, Single Nucleotide , Aged , Case-Control Studies , Cognition , DNA Methyltransferase 3A , Female , Humans , Male , Middle Aged
14.
Brain ; 138(Pt 5): 1327-38, 2015 May.
Article in English | MEDLINE | ID: mdl-25693589

ABSTRACT

Three sets of research criteria are available for diagnosis of Alzheimer's disease in subjects with mild cognitive impairment: the International Working Group-1, International Working Group-2, and National Institute of Aging-Alzheimer Association criteria. We compared the prevalence and prognosis of Alzheimer's disease at the mild cognitive impairment stage according to these criteria. Subjects with mild cognitive impairment (n = 1607), 766 of whom had both amyloid and neuronal injury markers, were recruited from 13 cohorts. We used cognitive test performance and available biomarkers to classify subjects as prodromal Alzheimer's disease according to International Working Group-1 and International Working Group-2 criteria and in the high Alzheimer's disease likelihood group, conflicting biomarker groups (isolated amyloid pathology or suspected non-Alzheimer pathophysiology), and low Alzheimer's disease likelihood group according to the National Institute of Ageing-Alzheimer Association criteria. Outcome measures were the proportion of subjects with Alzheimer's disease at the mild cognitive impairment stage and progression to Alzheimer's disease-type dementia. We performed survival analyses using Cox proportional hazards models. According to the International Working Group-1 criteria, 850 (53%) subjects had prodromal Alzheimer's disease. Their 3-year progression rate to Alzheimer's disease-type dementia was 50% compared to 21% for subjects without prodromal Alzheimer's disease. According to the International Working Group-2 criteria, 308 (40%) subjects had prodromal Alzheimer's disease. Their 3-year progression rate to Alzheimer's disease-type dementia was 61% compared to 22% for subjects without prodromal Alzheimer's disease. According to the National Institute of Ageing-Alzheimer Association criteria, 353 (46%) subjects were in the high Alzheimer's disease likelihood group, 49 (6%) in the isolated amyloid pathology group, 220 (29%) in the suspected non-Alzheimer pathophysiology group, and 144 (19%) in the low Alzheimer's disease likelihood group. The 3-year progression rate to Alzheimer's disease-type dementia was 59% in the high Alzheimer's disease likelihood group, 22% in the isolated amyloid pathology group, 24% in the suspected non-Alzheimer pathophysiology group, and 5% in the low Alzheimer's disease likelihood group. Our findings support the use of the proposed research criteria to identify Alzheimer's disease at the mild cognitive impairment stage. In clinical settings, the use of both amyloid and neuronal injury markers as proposed by the National Institute of Ageing-Alzheimer Association criteria offers the most accurate prognosis. For clinical trials, selection of subjects in the National Institute of Ageing-Alzheimer Association high Alzheimer's disease likelihood group or the International Working Group-2 prodromal Alzheimer's disease group could be considered.


Subject(s)
Alzheimer Disease/epidemiology , Cognitive Dysfunction/epidemiology , Adult , Aged , Aged, 80 and over , Alzheimer Disease/complications , Biomarkers/metabolism , Cognitive Dysfunction/etiology , Disease Progression , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Prevalence , Prognosis , Survival Analysis
15.
Alzheimers Dement ; 11(2): 195-206.e1, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25150733

ABSTRACT

We investigated the use of Alzheimer's disease (AD) biomarkers in European Alzheimer's Disease Consortium centers and assessed their perceived usefulness for the etiologic diagnosis of mild cognitive impairment (MCI). We surveyed availability, frequency of use, and confidence in diagnostic usefulness of markers of brain amyloidosis (amyloid positron emission tomography [PET], cerebrospinal fluid [CSF] Aß42) and neurodegeneration (medial temporal atrophy [MTA] on MR, fluorodeoxyglucose positron emission tomography [FDG-PET], CSF tau). The most frequently used biomarker is visually rated MTA (75% of the 37 responders reported using it "always/frequently") followed by CSF markers (22%), FDG-PET (16%), and amyloid-PET (3%). Only 45% of responders perceive MTA as contributing to diagnostic confidence, where the contribution was rated as "moderate". Seventy-nine percent of responders felt "very/extremely" comfortable delivering a diagnosis of MCI due to AD when both amyloid and neuronal injury biomarkers were abnormal (P < .02 versus any individual biomarker). Responders largely agreed that a combination of amyloidosis and neuronal injury biomarkers was a strongly indicative AD signature.


Subject(s)
Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/etiology , Practice Patterns, Physicians' , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/complications , Alzheimer Disease/diagnosis , Alzheimer Disease/pathology , Amyloid beta-Peptides/cerebrospinal fluid , Atrophy , Biomarkers/cerebrospinal fluid , Brain/diagnostic imaging , Brain/pathology , Cognitive Dysfunction/cerebrospinal fluid , Cognitive Dysfunction/pathology , Europe , Fluorodeoxyglucose F18 , Internet , Magnetic Resonance Imaging , Peptide Fragments/cerebrospinal fluid , Positron-Emission Tomography , Radiopharmaceuticals , Surveys and Questionnaires , tau Proteins/cerebrospinal fluid
16.
Alzheimers Res Ther ; 5(5): 44, 2013.
Article in English | MEDLINE | ID: mdl-24099236

ABSTRACT

INTRODUCTION: Knowledge of longitudinal progression in mild Alzheimer's disease (AD) is required for the evaluation of disease-modifying therapies. Our aim was to observe the effects of long-term cholinesterase inhibitor (ChEI) therapy in mild AD patients in a routine clinical setting. METHODS: This was a prospective, open-label, non-randomized, multicenter study of ChEI treatment (donepezil, rivastigmine or galantamine) conducted during clinical practice. The 734 mild AD patients (Mini-Mental State Examination (MMSE) score 20 to 26) were assessed at baseline and then semi-annually over three years. Outcome measures included the MMSE, Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog), Clinician's Interview-Based Impression of Change (CIBIC) and Instrumental Activities of Daily Living (IADL) scale. RESULTS: After three years of ChEI therapy, 31% (MMSE) and 33% (ADAS-cog) of the patients showed improved/unchanged cognitive ability, 33% showed improved/unchanged global performance and 14% showed improved/unchanged IADL capacity. Higher mean dose of ChEI and lower educational level were both predictors of more positive longitudinal cognitive and functional outcomes. Older participants and those with a better IADL score at baseline exhibited a slower rate of cognitive decline, whereas younger participants and those with higher cognitive status showed more preserved IADL ability over time. Gender and apolipoprotein E (APOE) genotype showed inconsistent results. Prediction models using the abovementioned scales are presented. CONCLUSIONS: In naturalistic mild AD patients, a marked deterioration in IADL compared with cognitive and global long-term outcomes was observed, indicating the importance of functional assessments during the early stages of the disease. The participants' time on ChEI treatment before inclusion in studies of new therapies might affect their rate of decline and thus the comparisons of changes in scores between various studies. An increased understanding of expected disease progression in different domains and potential predictors of disease progression is essential for assessment of future therapies in AD.

17.
Alzheimers Res Ther ; 5(1): 2, 2013.
Article in English | MEDLINE | ID: mdl-23286718

ABSTRACT

INTRODUCTION: Patients with Alzheimer's disease (AD) are currently treated with cholinesterase inhibitors, such as galantamine, without actual knowledge of its concentration in plasma. Our objective was to analyse potential relationships between galantamine concentration, galantamine dose, socio-demographic characteristics, body weight, body mass index (BMI), and treatment response. METHODS: Eighty-four patients with AD recruited from the Memory Clinic, Malmö, Sweden, and treated with galantamine were included in the study. Efficacy measures, including cognition (Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale - cognitive subscale (ADAS-cog)) and instrumental activities of daily living (IADL), were evaluated at baseline, 2 months after treatment initiation (MMSE only) and semi-annually over 3 years. At these assessments, blood samples were obtained for the analysis of the galantamine concentration, and body weight, BMI, drug dose and time from drug intake were recorded. RESULTS: All patients had a measurable concentration of galantamine at all assessments. The mean plasma concentration of the drug exhibited a positive linear association with dose (r = 0.513, P < 0.001). The dose did not differ between sexes. Negative linear associations between the galantamine plasma concentration and BMI (r = -0.454, P = 0.001) or body weight (r = -0.310, P = 0.034) were found exclusively in the male group. When mixed-effects models were used, the dose of galantamine (P < 0.001), time from drug intake (P < 0.001), and BMI (P = 0.021) or weight (P = 0.002) were factors that predicted the concentration, whereas sex, age, and cognitive and functional changes were not. CONCLUSIONS: High compliance to galantamine treatment was found among all patients in this naturalistic AD study. The impact of BMI or body weight on the plasma concentration of galantamine was important only among males. No relationship was observed between concentration and short-term treatment response or progression rate in terms of cognitive and functional abilities.

18.
BMC Neurol ; 12: 134, 2012 Nov 05.
Article in English | MEDLINE | ID: mdl-23126532

ABSTRACT

BACKGROUND: Activities of daily living (ADL) are an essential part of the diagnostic criteria for Alzheimer's disease (AD). A decline in ADL affects independent living and has a strong negative impact on caregiver burden. Functional response to cholinesterase inhibitor (ChEI) treatment and factors that might influence this response in naturalistic AD patients need investigating. The aim of this study was to identify the socio-demographic and clinical factors that affect the functional response after 6 months of ChEI therapy. METHODS: This prospective, non-randomised, multicentre study in a routine clinical setting included 784 AD patients treated with donepezil, rivastigmine or galantamine. At baseline and after 6 months of treatment, patients were assessed using several rating scales, including the Instrumental Activities of Daily Living (IADL) scale, Physical Self-Maintenance Scale (PSMS) and Mini-Mental State Examination (MMSE). Demographic and clinical characteristics were investigated at baseline. The functional response and the relationships of potential predictors were analysed using general linear models. RESULTS: After 6 months of ChEI treatment, 49% and 74% of patients showed improvement/no change in IADL and in PSMS score, respectively. The improved/unchanged patients exhibited better cognitive status at baseline; regarding improved/unchanged PSMS, patients were younger and used fewer anti-depressants. A more positive functional response to ChEI was observed in younger individuals or among those having the interaction effect of better preserved cognition and lower ADL ability. Patients with fewer concomitant medications or those using NSAIDs/acetylsalicylic acid showed a better PSMS response. CONCLUSIONS: Critical characteristics that may influence the functional response to ChEI in AD were identified. Some predictors differed from those previously shown to affect cognitive response, e.g., lower cognitive ability and older age predicted better cognitive but worse functional response.


Subject(s)
Activities of Daily Living/psychology , Alzheimer Disease/drug therapy , Cholinesterase Inhibitors/therapeutic use , Age Factors , Aged , Aged, 80 and over , Alzheimer Disease/psychology , Cognition , Disabled Persons , Donepezil , Female , Galantamine/therapeutic use , Humans , Indans/therapeutic use , Linear Models , Male , Middle Aged , Neuropsychological Tests , Phenylcarbamates/therapeutic use , Piperidines/therapeutic use , Rivastigmine , Treatment Outcome
19.
Arch Gen Psychiatry ; 69(1): 98-106, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22213792

ABSTRACT

CONTEXT: Early detection of prodromal Alzheimer disease (AD) is important because new disease-modifying therapies are most likely to be effective when initiated during the early stages of disease. OBJECTIVES: To assess the ability of the cerebrospinal fluid (CSF) biomarkers total tau (T-tau), phosphorylated tau (P-tau), and ß-amyloid 1-42 (Aß42) to predict future development of AD dementia within 9.2 years in patients with mild cognitive impairment (MCI) and to compare CSF biomarkers between early and late converters to AD. DESIGN: A clinical study with a median follow-up of 9.2 years (range, 4.1-11.8 years). SETTING: Memory disorder clinic. Patients A total of 137 patients with MCI who underwent lumbar puncture at baseline. MAIN OUTCOME MEASURE Conversion to AD dementia. RESULTS: During follow-up, 72 patients (53.7%) developed AD and 21 (15.7%) progressed to other forms of dementia. At baseline, CSF Aß42 levels were reduced and T-tau and P-tau levels were elevated in patients who converted to AD during follow-up compared with nonconverters (P < .001). Baseline CSF Aß42 levels were equally reduced in patients with MCI who converted to AD within 0 to 5 years (early converters) compared with those who converted between 5 and 10 years (late converters). However, CSF T-tau and P-tau levels were significantly higher in early converters vs late converters. A baseline Aß42:P-tau ratio predicted the development of AD within 9.2 years with a sensitivity of 88%, specificity of 90%, positive predictive value of 91%, and negative predictive value of 86%. CONCLUSIONS: Approximately 90% of patients with MCI and pathologic CSF biomarker levels at baseline develop AD within 9 to 10 years. Levels of Aß42 are already fully decreased at least 5 to 10 years before conversion to AD dementia, whereas T-tau and P-tau seem to be later markers. These results provide direct support in humans for the hypothesis that altered Aß metabolism precedes tau-related pathology and neuronal degeneration.


Subject(s)
Alzheimer Disease/diagnosis , Amyloid beta-Peptides/cerebrospinal fluid , Cognitive Dysfunction/diagnosis , Peptide Fragments/cerebrospinal fluid , tau Proteins/cerebrospinal fluid , Aged , Alzheimer Disease/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Cognitive Dysfunction/cerebrospinal fluid , Female , Follow-Up Studies , Humans , Male , Predictive Value of Tests , Time Factors
20.
Eur J Health Econ ; 13(5): 561-8, 2012 Oct.
Article in English | MEDLINE | ID: mdl-21822729

ABSTRACT

BACKGROUND/AIMS: Improved data and methods are needed for modeling disease progression in Alzheimer's disease (AD) for economic evaluation of treatments. The aim is to estimate prediction models for long-term AD progression and subsequently economic outcomes. METHODS: Three-year follow-up data on 435 patients treated with the cholinesterase inhibitor donepezil in clinical practise were analyzed. Regression models were estimated for long-term prediction of decline in cognitive function (ADAS-cog) and activities in daily living (ADL) ability, risk of institutionalization and costs of care. RESULTS: The cognitive deterioration was estimated at between 1.6 and 4 ADAS-cog points per every 6 months, increasing with disease severity. Cognitive function was an important predictor of ADL-ability, which itself was the most important predictor of the risk of institutionalization and costs of care. Combining all models in a cross-validation process generated accurate predictions of costs of care at each 6 months follow-up. CONCLUSION: The proposed methods for representing AD progression and economic outcomes can be used in micro-simulation models for the economic evaluation of new treatments.


Subject(s)
Alzheimer Disease/economics , Disease Progression , Health Care Costs , Indans/therapeutic use , Nootropic Agents/economics , Piperidines/therapeutic use , Activities of Daily Living , Aged , Alzheimer Disease/drug therapy , Alzheimer Disease/pathology , Cognition , Donepezil , Female , Health Status Indicators , Humans , Indans/economics , Institutionalization , Longitudinal Studies , Male , Models, Economic , Nootropic Agents/therapeutic use , Piperidines/economics , Psychometrics , Regression Analysis , Severity of Illness Index , Sweden
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