A systematic review of cognitive decline in dementia with Lewy bodies versus Alzheimer's disease

Exploring the impact of community-based choral participation on cognitive function and well-being for persons with dementia: evidence from the Voices in Motion project

OBJECTIVES

Music-based interventions are postulated to mitigate cognitive decline in individuals with dementia. However, the mechanisms underlying why music-based interventions facilitate cognitive benefits remain unknown. The present study examines whether a choral intervention can modulate patterns of cognitive change in persons with dementia and whether within-person variation in affect is associated with this change.

METHODS

Thirty-three older adults with dementia engaged weekly in the Voices in Motion (ViM) study consisting of 3 choral seasons spanning 18-months. Performance on the Mini-Mental State Examination (MMSE) and the Positive and Negative Affect Schedule was assessed monthly within each choral season using a longitudinal intensive repeated-measures design. Three-level multilevel models were employed to disaggregate between- and within-person effects across short- (month-to-month) and long-term (season-to-season) intervals.

RESULTS

ViM participants exhibited an annual MMSE decline of 1.8 units, notably less than the clinically meaningful 3.3 units indicated by non-intervention literature. Further, variability in negative affect shared a within-person time-varying association with MMSE performance; decreases in negative affect, relative to one's personal average, were linked to corresponding improvements in cognitive function.

CONCLUSION

Engagement in the ViM choral intervention may attenuate cognitive decline for persons with dementia via a reduction of psychological comorbidities such as elevated negative affect.

Clinical Trajectories at the End of Life in Dementia Patients With Alzheimer Disease and Lewy Body Neuropathologic Changes

BACKGROUND AND OBJECTIVES

Evaluating and understanding the heterogeneity in dementia course has important implications for clinical practice, healthcare decision-making, and research. However, inconsistent findings have been reported with regard to the disease courses of the two most common dementias, Alzheimer's disease (AD) and Dementia with Lewy bodies (DLB). Using autopsy-confirmed diagnoses, we aimed to examine the disease trajectories in the years before death among dementia patients with pure AD, pure DLB, or mixed (AD and DLB) pathologies.

METHODS

The current retrospective longitudinal study included 62 participants with autopsy-confirmed diagnoses of pure AD (n=34), mixed AD and DLB (AD+DLB, n = 17), or pure DLB (n=11) from the Predictors 2 Cohort Study, a prospective, clinic-based, cohort of dementia patients. Generalized estimating equation models, with time zero at death, were used to examine the trajectory of cognition (Folstein Mini-Mental State Examination, MMSE), function (Activities of Daily Living, ADL), and dependence scale among patients with different autopsy-confirmed diagnosis (pure AD, AD+DLB, and pure DLB). The models were adjusted for age, sex, education, and baseline features including extrapyramidal signs, MMSE, ADL, and dependence scale.

RESULTS

The participants on average received 9.4±4.6 assessments at 6-month intervals during a mean 5.4±2.9 years of follow-up time. The three groups were similar in both cognition and function status at baseline. Cognition and function were highly correlated among AD+DLB patients but not in pure AD or pure DLB patients at baseline. Patients of the three groups all declined in both cognition and function but had different trajectories of decline. More specifically, the pure DLB patients experienced approximately double the rate of both cognitive decline and functional decline than the pure AD patients, and the mixed pathology group showed double the rate of functional decline as compared to pure AD patients.

DISCUSSION

In this longitudinal study, we found that among patients with dementia, those with Lewy body pathology experienced faster cognitive and functional decline than those with pure AD pathology.

Challenges in Predicting Cognitive Decline in Dementia with Lewy Bodies

Despite being the second most common form of neurodegenerative dementia, dementia with Lewy bodies (DLB) is under-recognized and carries a worse prognosis than other subtypes of the condition. Cognitive impairment is a cardinal feature of all types of dementia and DLB presents with a distinct profile with deficits in attention, executive function, and visuoperceptual abilities. This difference from Alzheimer's disease and the common presence of neuropsychiatric symptoms may lead to challenges in predicting cognitive decline in this patient population. Firstly, the diagnosis of DLB is often delayed in clinical practice leading to variability from which time point in the disease course cognitive decline is measured. Secondly, the most frequently used measurement tools for cognitive difficulties focus on memory and naming rather than the domains affected by DLB. While there is now largely a consensus which tools are useful in diagnosing DLB, their validity in assessing deteriorating cognition is less clear. Thirdly, the presence of fluctuating cognition, the propensity to develop delirium episodes, as well as difficulties in distinguishing the two entities in clinical practice make it difficult to predict the disease course. Sleep disturbances are likely to influence cognitive decline but require further study in patients within established DLB. Fourthly, as in most cases of dementia, neuropathological comorbidities are frequently present in DLB. While the influence of Alzheimer's pathology on cognitive decline in DLB is comparatively well understood, the impact of other pathologies remains unclear. The recent definition of research criteria for mild cognitive impairment in DLB could facilitate earlier diagnosis and more structured follow-up. Assessment tools measuring cognitive domains predominantly affected in DLB need to be more consistently used in longitudinal studies and clinical practice, as well as concurrent measures of fluctuations in cognition. Greater availability of biomarkers and digital healthcare solutions can play an important role in enabling more accurate monitoring and prediction of cognitive decline in DLB.

Late-Life Cognitive Trajectories and their Associated Lifestyle Factors

Significant variability exists in the trajectories of late-life cognitive decline; however, their associated lifestyle factors remain less studied. We examined these trajectories among elderly participants from the recent five waves (at three-year intervals) of the Chinese Longitudinal Healthy Longevity Study (CLHLS) from 2002 to 2014. Participants from this cohort were included if they completed at least four waves of measurements. Mini-Mental State Examination (MMSE) scores, demographics, medical diagnoses (e.g., hypertension, diabetes, and heart disease), and lifestyle-related information (e.g., smoking, drinking alcohol, and exercise) were collected from participants (N = 2,584; mean age at baseline = 73.3) at least four times across 12 years. MMSE scores were entered into a latent class mixed model analysis. Subsequently, demographic, medical, and lifestyle predictors were entered into multinomial logistic regression models to predict the trajectories. One of the four emerged classes (no decline) was characterized by an absence of cognitive decline; the other three exhibited various degrees of cognitive decline. The inclusion of lifestyle factors significantly improved the prediction of the different trajectories, above and beyond demographics and medical variables; the 'no decline' class was significantly more likely to report exercising regularly. Changes in cognitive functioning across the late-life period are characterized by multiple trajectories. Cognitive decline is not inevitable across the late-life period; the absence of such cognitive decline is partly explained by certain lifestyle factors.

Health promotion intervention for people with early-stage dementia: A quasi-experimental study

INTRODUCTION

With the limited advancements in medical treatment, there is a growing need for supporting people with early-stage dementia adjust to their diagnosis and improve their quality of life. This study aimed to investigate the effects of a 12-week health promotion course for people with early-stage dementia.

METHODS

Quasi-experimental, single group, pretest-posttest design. A total of 108 persons with dementia participated in this study, and for each participant, a carer was interviewed. The 12-week health promotion intervention consisted of 2-hr sessions at weekly intervals. Outcome measures were cognition, measured by Mini-Mental State Examination, personal, and instrumental activities of daily living (P-ADL and I-ADL), measured by Lawton and Brody's Physical Self-Maintenance Scale and Instrumental Activities of Daily Living Scale, self-rated health, measured by the European Quality of life Visual Analogue Scale, depressive symptoms, measured by the Cornell Scale for Depression in Dementia, and neuropsychiatric symptoms, measured by The Neuropsychiatric Inventory. Assessments were conducted at baseline and at follow-up 1-2 months postintervention.

RESULTS

The results demonstrate a small but statistically significant improvement in depressive symptoms (p = .015) and in self-rated health (p = .031). The results also demonstrated a small statistically significant decline in the participants' I-ADL (p = .007). The participants' cognitive function, P-ADL, and neuropsychiatric symptoms were stable during the 4-month follow-up.

CONCLUSION

This study demonstrates promising results with regard to the benefit of attending a 12-week health promotion intervention in promoting health and well-being in people with early-stage dementia. With the majority of participants with early-stage dementia living at home without any healthcare services in a vulnerable stage of the condition, this study makes an important contribution to highlighting the need for, and benefit of, educational approaches for this population.

Self-management and HeAlth Promotion in Early-stage dementia with e-learning for carers (SHAPE): study protocol for a multi-centre randomised controlled trial

BACKGROUND

With an increasing number of people with dementia worldwide and limited advancement in medical treatments, the call for new and cost-effective approaches is crucial. The utility of self-management has been proven in certain chronic conditions. However, very little work has been undertaken regarding self-management in people with dementia.

METHODS

The SHAPE trial will include 372 people with mild to moderate dementia to evaluate the effectiveness and cost-effectiveness of an educational programme combining approaches of self-management, health promotion, and e-learning for care partners. The study is a multi-site, single-randomised, controlled, single-blinded trial with parallel arms. The intervention arm is compared with treatment as usual. The intervention comprises a 10-week course delivered as group sessions for the participants with dementia. The sessions are designed to develop self-management skills and to provide information on the nature of the condition and the development of healthy behaviours in a supportive learning environment. An e-learning course will be provided for care partners which covers similar and complementary material to that discussed in the group sessions for the participant with dementia.

DISCUSSION

This trial will explore the effect of the SHAPE group intervention on people with mild to moderate dementia in terms of self-efficacy and improvement in key health and mental health outcomes and cost-effectiveness, along with carer stress and knowledge of dementia.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04286139, registered prospectively February 26, 2020, https://clinicaltrials.gov/ct2/show/NCT04286139.

Cognitive tests aid in clinical differentiation of Alzheimer's disease versus Alzheimer's disease with Lewy body disease: Evidence from a pathological study

INTRODUCTION

Clinical differentiation between Alzheimer's disease (AD) and AD with Lewy body disease (LBD) is relatively imprecise. The current study examined pathologically confirmed group differences in neuropsychological functioning, and the classification ability of specific tests.

METHODS

Fifty-one participants with postmortem diagnoses of AD (n = 34) and AD plus LBD (n = 17) were drawn from the Predictors Study. One-way analyses of variance (ANOVAs) and χ² analyses examined group differences in neuropsychological performance. Binary logistic regressions examined predictive utility of specific tests for pathological diagnosis.

RESULTS

Individuals with AD had better visuoconstruction (P = .006), phonemic fluency (P = .08), and processing speed than AD plus LBD (P = .013). No differences were found in memory, naming, semantic fluency, or set-switching. Processing speed and visuoconstruction predicted pathologic group (P = .03).

DISCUSSION

Processing speed and visuoconstruction predicted postmortem diagnosis of AD versus AD plus LBD. Current results offer guidance in the selection and interpretation of neuropsychological tests to be used in the differential diagnosis of early dementia.

Exploratory study on microRNA profiles from plasma-derived extracellular vesicles in Alzheimer's disease and dementia with Lewy bodies

Background

Because of the increasing life expectancy in our society, aging-related neurodegenerative disorders are one of the main issues in global health. Most of these diseases are characterized by the deposition of misfolded proteins and a progressive cognitive decline. Among these diseases, Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB) are the most common types of degenerative dementia. Although both show specific features, an important neuropathological and clinical overlap between them hampers their correct diagnosis. In this work, we identified molecular biomarkers aiming to improve the misdiagnosis between both diseases.

Methods

Plasma extracellular vesicles (EVs) -from DLB, AD and healthy controls- were isolated using size-exclusion chromatography (SEC) and characterized by flow cytometry, Nanoparticle Tracking Analysis (NTA) and cryo-electron microscopy. Next Generation Sequencing (NGS) and related bibliographic search was performed and a selected group of EV-associated microRNAs (miRNAs) was analysed by qPCR.

Results

Results uncovered two miRNAs (hsa-miR-451a and hsa-miR-21-5p) significantly down-regulated in AD samples respect to DLB patients, and a set of four miRNAs (hsa-miR-23a-3p, hsa-miR-126-3p, hsa-let-7i-5p, and hsa-miR-151a-3p) significantly decreased in AD respect to controls. The two miRNAs showing decreased expression in AD in comparison to DLB provided area under the curve (AUC) values of 0.9 in ROC curve analysis, thus suggesting their possible use as biomarkers to discriminate between both diseases. Target gene analysis of these miRNAs using prediction online tools showed accumulation of phosphorylation enzymes, presence of proteasome-related proteins and genes involved in cell death among others.

Conclusion

Our data suggest that plasma-EV associated miRNAs may reflect a differential profile for a given dementia-related disorder which, once validated in larger cohorts of patients, could help to improve the differential diagnosis of DLB versus AD.

Electronic supplementary material

The online version of this article (10.1186/s40035-019-0169-5) contains supplementary material, which is available to authorized users.

Influence of Lewy Pathology on Alzheimer's Disease Phenotype: A Retrospective Clinico-Pathological Study

Background:

Studies have shown the frequent coexistence of Lewy pathology (LP) in Alzheimer’s Disease (AD).

Objective:

The aim of this study was to determine the influence of LP on the clinical and cognitive phenotype in a cohort of patients with a neuropathological diagnosis of AD.

Methods:

We reviewed neuropathologically proven AD cases, reaching Braak stages V and VI in the brain banks of Lille and Paris between 1993 and 2016, and classified them according to LP extension (amygdala, brainstem, limbic, or neocortical). We then searched patient files for all available clinical and neuropsychiatric features and neuropsychological data.

Results:

Thirty-three subjects were selected for this study, among which 16 were devoid of LP and 17 presented AD with concomitant LP. The latter were stratified into two subgroups according to LP distribution: 7 were AD with amygdala LP and 10 were AD with ‘classical’ (brainstem, limbic or neocortical) LP. When analyzing the incidence of each clinical feature at any point during the disease course, we found no significant difference in symptom frequency between the three groups. However, fluctuations appeared significantly earlier in patients with classical LP (2±3.5 years) than in patients without LP (7±1.7 years) or with amygdala LP (8±2.8 years; p < 0.01). There was no significant difference in cognitive profiles.

Conclusion:

Our findings suggest that the influence of LP on the clinical phenotype of AD is subtle. Core features of dementia with Lewy bodies do not allow clinical diagnosis of a concomitant LP on a patient-to-patient basis.

Cloud-Based Brain Magnetic Resonance Image Segmentation and Parcellation System for Individualized Prediction of Cognitive Worsening

For patients with cognitive disorders and dementia, accurate prognosis of cognitive worsening is critical to their ability to prepare for the future, in collaboration with health-care providers. Despite multiple efforts to apply computational brain magnetic resonance image (MRI) analysis in predicting cognitive worsening, with several successes, brain MRI is not routinely quantified in clinical settings to guide prognosis and clinical decision-making. To encourage the clinical use of a cutting-edge image segmentation method, we developed a prediction model as part of an established web-based cloud platform, MRICloud. The model was built in a training dataset from Alzheimer's Disease Neuroimaging Initiative (ADNI) where baseline MRI scans were combined with clinical data over time. Each MRI was parcellated into 265 anatomical units based on the MRICloud fully automated image segmentation function, to measure the volume of each parcel. The Mini Mental State Examination (MMSE) was used as a measure of cognitive function. The normalized volume of 265 parcels, combined with baseline MMSE score, age, and sex were input variables for a Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis, with MMSE change in the subsequent two years as the target for prediction. A leave-one-out analysis performed on the training dataset estimated a correlation coefficient of 0.64 between true and predicted MMSE change. A receiver operating characteristic (ROC) analysis estimated a sensitivity of 0.88 and a specificity of 0.76 in predicting substantial cognitive worsening after two years, defined as MMSE decline of ≥4 points. This MRICloud prediction model was then applied to a test dataset of clinically acquired MRIs from the Johns Hopkins Memory and Alzheimer's Treatment Center (MATC), a clinical care setting. In the latter setting, the model had both sensitivity and specificity of 1.0 in predicting substantial cognitive worsening. While the MRICloud prediction model demonstrated promise as a platform on which computational MRI findings can easily be extended to clinical use, further study with a larger number of patients is needed for validation.

A Review of Dementia with Lewy Bodies' Impact, Diagnostic Criteria and Treatment

Dementia with Lewy bodies is one of the most common causes of dementia. It is not as common as Alzheimer's disease; the general public's awareness of the disease is poor in comparison. Its effects on caregivers and patients alike are not well known to the general population. There are currently no FDA-approved medications specifically for the treatment of DLB. Many of the medications that are approved for Alzheimer's disease are widely used in the treatment of DLB with varying degrees of success. Treatment of DLB is life long and requires a dedicated team of physicians and caregivers to minimize the degree of morbidity and mortality experienced by the patients suffering from the disease as it progresses.

A Longitudinal Study of Neurocognition in Dementia with Lewy Bodies Compared to Alzheimer's Disease

Introduction

There are relatively few longitudinal studies on the differences in cognitive decline between Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB), and the majority of existing studies have suboptimal designs.

Aim

We investigated the differences in cognitive decline in AD compared to DLB over 4 years and cognitive domain predictors of progression.

Methods

In a longitudinal study, 266 patients with first-time diagnosis of mild dementia were included and followed annually. The patients were tested annually with neuropsychological tests and screening instruments [MMSE (Mini-Mental Status Examination), Clinical Dementia Rating (CDR), the second edition of California Verbal Learning Test (CVLT-II), Trail Making Test A & B (TMT A & B), Stroop test, Controlled Oral Word Associations Test (COWAT) animal naming, Boston Naming Test, Visual Object and Space Perception Battery (VOSP) Cubes and Silhouettes]. Longitudinal analyses were performed with linear mixed effects (LME) models and Cox regression. Both specific neuropsychological tests and cognitive domains were analyzed.

Results

This study sample comprised 119 AD and 67 DLB patients. In TMT A, the DLB patients had a faster decline over 4 years than patients with AD (p = 0.013). No other longitudinal differences in specific neuropsychological tests were found. Higher executive domain scores at baseline were associated with a longer time to reach severe dementia (CDR = 3) or death for the total sample (p = 0.032). High or low visuospatial function at baseline was not found to be associated with cognitive decline (MMSE) or progression of dementia severity (CDR) over time.

Conclusion

Over 4 years, patients with DLB had a faster decline in TMT A than patients with AD, but this should be interpreted cautiously. Beyond this, there was little support for faster decline in DLB patients neuropsychologically than in AD patients.

Long-Term Cognitive Decline in Dementia with Lewy Bodies in a Large Multicenter, International Cohort

BACKGROUND/OBJECTIVE

The aim of this study was to describe the rate and clinical predictors of cognitive decline in dementia with Lewy bodies (DLB), and compare the findings with Alzheimer's disease (AD) and Parkinson's disease dementia (PDD) patients.

METHODS

Longitudinal scores for the Mini-Mental State Examination (MMSE) in 1,290 patients (835 DLB, 198 PDD, and 257 AD) were available from 18 centers with up to three years longitudinal data. Linear mixed effects analyses with appropriate covariates were used to model MMSE decline over time. Several subgroup analyses were performed, defined by anti-dementia medication use, baseline MMSE score, and DLB core features.

RESULTS

The mean annual decline in MMSE score was 2.1 points in DLB, compared to 1.6 in AD (p = 0.07 compared to DLB) and 1.8 in PDD (p = 0.19). Rates of decline were significantly higher in DLB compared to AD and PDD when baseline MMSE score was included as a covariate, and when only those DLB patients with an abnormal dopamine transporter SPECT scan were included. Decline was not predicted by sex, baseline MMSE score, or presence of specific DLB core features.

CONCLUSIONS

The average annual decline in MMSE score in DLB is approximately two points. Although in the overall analyses there were no differences in the rate of decline between the three neurodegenerative disorders, there were indications of a more rapid decline in DLB than in AD and PDD. Further studies are needed to understand the predictors and mechanisms of cognitive decline in DLB.

Survival and Causes of Death Among People With Clinically Diagnosed Synucleinopathies With Parkinsonism: A Population-Based Study

Importance

To our knowledge, a comprehensive study of the survival and causes of death of persons with synucleinopathies compared with the general population has not been conducted. Understanding the long-term outcomes of these conditions may inform patients and caregivers of the expected disease duration and may help with care planning.

Objective

To compare survival rates and causes of death among patients with incident, clinically diagnosed synucleinopathies and age- and sex-matched referent participants.

Design, Setting, and Participants

This population-based study used the Rochester Epidemiology Project medical records-linkage system to identify all residents in Olmsted County, Minnesota, who received a diagnostic code of parkinsonism from 1991 through 2010. A movement-disorders specialist reviewed the medical records of each individual to confirm the presence of parkinsonism and determine the type of synucleinopathy. For each confirmed patient, an age- and sex-matched Olmsted County resident without parkinsonism was also identified.

Main Outcomes and Measures

We determined the age- and sex-adjusted risk of death for each type of synucleinopathy, the median time from diagnosis to death, and the causes of death.

Results

Of the 461 patients with synucleinopathies, 279 (60.5%) were men, and of the 452 referent participants, 272 (60.2%) were men. From 1991 through 2010, 461 individuals received a diagnosis of a synucleinopathy (309 [67%] of Parkinson disease, 81 [17.6%] of dementia with Lewy bodies, 55 [11.9%] of Parkinson disease dementia, and 16 [3.5%] of multiple system atrophy with parkinsonism). During follow-up, 68.6% (n = 316) of the patients with synucleinopathies and 48.7% (n = 220) of the referent participants died. Patients with any synucleinopathy died a median of 2 years earlier than referent participants. Patients with multiple system atrophy with parkinsonism (hazard ratio, 10.51; 95% CI, 2.92-37.82) had the highest risk of death compared with referent participants, followed by those with dementia with Lewy bodies (hazard ratio, 3.94; 95% CI, 2.61-5.94), Parkinson disease with dementia (hazard ratio, 3.86; 95% CI, 2.36-6.30), and Parkinson disease (hazard ratio, 1.75; 95% CI, 1.39-2.21). Neurodegenerative disease was the most frequent cause of death listed on the death certificate for patients, and cardiovascular disease was the most frequent cause of death among referent participants.

Conclusions and Relevance

Individuals with multiple system atrophy with parkinsonism, dementia with Lewy bodies, and Parkinson disease dementia have increased mortality compared with the general population. The mortality among persons with Parkinson disease is only moderately increased compared with the general population.

Long-term cognitive outcome of Alzheimer's disease and dementia with Lewy bodies: dual disease is worse

Background

Longitudinal studies of dementia with Lewy bodies (DLB) are rare. Clinically, DLB is usually considered to worsen into Alzheimer’s disease (AD). The aim of our study was to compare the rate of the cognitive decline in DLB, AD, and the association of the two diseases (AD + DLB).

Methods

Using the Regional Network for Diagnostic Aid and Management of Patients with Cognitive Impairment database, which includes all the patients seen at all memory clinics (medical consultation and day hospitals) in four French regions, and beta regression, we compared the longitudinal the Mini-Mental State Examination scores of 1159 patients with AD (n = 1000), DLB (n = 131) and AD + DLB (association of the two) (n = 28) during follow-up of at least 4 years.

Results

The mean follow-up of the patients was 5.88 years. Using beta regression without propensity scores, the comparison of the decline of patients with AD and patients with DLB did not show a significant difference, but the decline of patients with AD + DLB was worse than that of either patients with DLB (P = 0.006) or patients with AD (P < 0.001). Using beta regression weighted by a propensity score, comparison of patients with AD and patients with DLB showed a faster decline for patients with DLB (P < 0.001). The comparison of the decline of patients with AD + DLB with that of patients with DLB (P < 0.001) and patients with AD (P < 0.001) showed that the decline was clearly worse in the patients with dual disease.

Conclusions

Whatever the analysis, the rate of decline is faster in patients with AD + DLB dual disease. The identification of such patients is important to enable clinicians to optimise treatment and care and to better inform and help patients and caregivers.

Impact of Alzheimer's Disease, Lewy Body and Vascular Co-Pathologies on Clinical Transition to Dementia in a National Autopsy Cohort

AIMS

We examined the effect of vascular or Lewy body co-pathologies in subjects with autopsy-confirmed Alzheimer's disease (AD) on the rate of cognitive and functional decline and transition to dementia.

METHODS

In an autopsy sample of prospectively characterized subjects from the National Alzheimer's Coordinating Center database, neuropathology diagnosis was used to define the groups of pure AD (pAD, n = 84), mixed vascular and AD (ADV, n = 54), and mixed Lewy body disease and AD (ADLBD, n = 31). Subjects had an initial Clinical Dementia Rating-Global (CDR-G) score <1, Mini-Mental State Examination ≥15, a final visit CDR-G >1, ≥3 evaluations, and Braak tangle stage ≥III. We compared the rate of cognitive and functional decline between the groups.

RESULTS

The rate of functional and cognitive decline was lower for ADV, and ADV patients had less severe deficits on CDR-G and the CDR-Sum of Boxes scores at the last visit than pAD and ADLBD patients. No significant differences were noted between ADLBD and pAD patients. After controlling for age at death, the odds of reaching CDR ≥1 at the last visit were lower in the ADV subjects compared to the pAD subjects.

CONCLUSIONS

The mean rate of functional and cognitive decline among ADV subjects was slower than among either pAD or ADLBD patients. Vascular pathology did not increase the odds of attaining CDR ≥1 when occurring with AD in this national cohort.

Differences in Rate of Cognitive Decline and Caregiver Burden between Alzheimer's Disease and Vascular Dementia: a Retrospective Study

Few studies have explored the rate of cognitive decline and caregiver burden within the context of a specialized memory clinic. When this was done, the focus was largely on functional decline related to Alzheimer's disease (AD). Our goal was to compare the longitudinal decline of AD patients to those with Vascular Dementia (VaD) on Mini-Mental State Examination (MMSE). We further explored the differential impact on caregiver burden. We retrospectively studied 237 charts from patients seen at our Memory Clinic between 2006 and 2012. The data was collected over 17 years. Cohorts were formed by excluding conditions other than AD and VaD, and including patients who had been assessed at least twice with the MMSE (AD: n = 83; mean age: 67.7 yo; VaD: n = 32; mean age: 73.3yo). A small group of 36 caregivers was surveyed by phone to explore caregiver burden. Results indicated that the natural history of MMSE changes in AD patients differed significantly from that of patients with VaD (F = 10.41, p<0.0014), with AD patients showing more cognitive decline over time. Sadness, stress/anxiety, fatigue, and sleep disorders were reported as the main preoccupations by caregivers and its impact was rated as 'severe' in 50% of cases. Altogether, this study provides further insight into the natural history of cognitive decline in AD and VaD. Future studies should explore the progression of dementing disorders in larger cohorts using prospective methodological designs.

Cognitive decline in dementia with Lewy bodies: a 5-year prospective cohort study

OBJECTIVES

We report the cognitive decline in persons diagnosed with mild dementia with Lewy bodies (DLB) and mild Alzheimer's disease (AD) during 5 years of annual follow-ups.

METHODS

Patients were recruited into the study from geriatric, psychiatric and neurology clinics in Western Norway during 2005-2013. They were diagnosed according to clinical consensus criteria, based on standardised clinical rating scales. Autopsy-based diagnoses were available for 20 cases. Cognitive decline for up to 5 years was assessed using the Clinical Dementia Rating (CDR) scale and the Mini-Mental State Examination (MMSE). Survival analysis including Cox regression (time to reach severe dementia) and linear mixed-effects (lme) modelling were used to model the decline on MMSE.

RESULTS

At least one follow-up assessment was available for 67 patients with DLB and 107 patients with AD, with a median follow-up time of 4.3 years. The time to reach severe dementia was significantly shorter in DLB (median 1793 days) compared with AD (1947 days; p=0.033), and the difference remained significant in the multiple Cox regression analysis (HR=2.0, p<0.02). In the adjusted lme model, MMSE decline was faster in DLB (annual decline 4.4 points) compared with AD (3.2 points; p<0.008).

CONCLUSIONS

Our findings show that from the mild dementia stage, patients with DLB have a more rapid cognitive decline than in AD. Such prognostic information is vital for patients and families and crucial for planning clinical trials and enabling health economic modelling.

MMSE and MoCA in Parkinson's disease and dementia with Lewy bodies: a multicenter 1-year follow-up study

The Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) are the most commonly used scales to test cognitive impairment in Lewy body disease (LBD), but there is no consensus on which is best suited to assess cognition in clinical practice and most sensitive to cognitive decline. Retrospective cohort study of 265 LBD patients [Parkinson's disease (PD) without dementia (PDnD, N = 197), PD with dementia (PDD, N = 40), and dementia with Lewy bodies (DLB, N = 28)] from an international consortium who completed both the MMSE and MoCA at baseline and 1-year follow-up (N = 153). Percentage of relative standard deviation (RSD%) at baseline was the measure of inter-individual variance, and estimation of change (Cohen's d) over time was calculated. RSD% for the MoCA (21 %) was greater than for the MMSE (13 %) (p = 0.03) in the whole group. This difference was significant only in PDnD (11 vs. 5 %, p < 0.01), but not in PDD (30 vs. 19 %, p = 0.37) or DLB (15 vs. 14 %, p = 0.78). In contrast, the 1-year estimation of change did not differ between the two tests in any of the groups (Cohen's effect <0.20 in each group). MMSE and MoCA are equal in measuring the rate of cognitive changes over time in LBD. However, in PDnD, the MoCA is a better measure of cognitive status as it lacks both ceiling and floor effects.

Genetic markers in biological fluids for aging-related major neurocognitive disorder

Aging-related major neurocognitive disorder (NCD), formerly named dementia, comprises of the different acquired diseases whose primary deficit is impairment in cognitive functions such as complex attention, executive function, learning and memory, language, perceptual/motor skills, and social cognition, and that are related to specific brain regions and/or networks. According to its etiology, the most common subtypes of major NCDs are due to Alzheimer' s disease (AD), vascular disease (VaD), Lewy body disease (LBD), and frontotemporal lobar degeneration (FTLD). These pathologies are frequently present in mixed forms, i.e., AD plus VaD or AD plus LBD, thus diagnosed as due to multiple etiologies. In this paper, the definitions, criteria, pathologies, subtypes and genetic markers for the most common age-related major NCD subtypes are summarized. The current diagnostic criteria consider cognitive decline leading to major NCD or dementia as a progressive degenerative process with an underlying neuropathology that begins before the manifestation of symptoms. Biomarkers associated with this asymptomatic phase are being developed as accurate risk factor and biomarker assessments are fundamental to provide timely treatment since no treatments to prevent or cure NCD yet exist. Biological fluid assessment represents a safer, cheaper and less invasive method compared to contrast imaging studies to predict NCD appearance. Genetic factors particularly have a key role not only in predicting development of the disease but also the age of onset as well as the presentation of comorbidities that may contribute to the disease pathology and trigger synergistic mechanisms which may, in turn, accelerate the neurodegenerative process and its resultant behavioral and functional disorders.