Consensus guidelines for the clinical and pathologic diagnosis of dementia with Lewy bodies (DLB): report of the consortium on DLB international workshop

The standardization of cerebrospinal fluid markers and neuropathological diagnoses brings to light the frequent complexity of concomitant pathology in Alzheimer's disease: The next challenge for biochemical markers?

During the last two decades, neuropathological examination of the brain has evolved both technically and scientifically. The increasing use of immunohistochemistry to detect protein aggregates paralleled a better understanding of neuroanatomical progression of protein deposition. As a consequence, an international effort was achieved to standardize hyperphosphorylated-Tau (phospho-TAU), ßAmyloid (Aß), alpha syncuclein (alpha-syn), phosphorylated transactive response DNA-binding protein 43 (phospho-TDP43) and vascular pathology detection. Meanwhile harmonized staging systems emerged in order to increase inter rater reproducibility. Therefore, a refined definition of Alzheimer's disease was recommended., a clearer picture of the neuropathological lesions diversity emerged secondarily to the systematic assessment of concomitant pathology highlighting finally a low rate of pure AD pathology. This brings new challenges to laboratory medicine in the field of cerebrospinal fluid (CSF) markers of Alzheimer's disease: how to further validate total Tau, phospho-TAU, Aß40 and Aß42 and new marker level cut-offs while autopsy rates are declining?

Vascular dementia encoding in the French nationwide discharge summary database (PMSI): Variability over the 2007-2017 period

OBJECTIVE

Vascular dementia (VaD) is the second leading cause of dementia. Diagnostic criteria have evolved from the concept of multiple infarctions to different subtypes: acute onset VaD, subcortical VaD, mixed cortical and subcortical VaD. Our aim was to analyze the evolution in the coding of these different subtypes of VaD in the French nationwide exhaustive hospital discharge database (PMSI) between 2007 and 2017.

METHOD

We included all principal diagnoses of VaD in the PMSI hospital stays from 2007 to 2017.

RESULTS

Between 2007 and 2017, we show a relative decrease in the number of hospital stays for VaD compared to all hospital stays (0.0437% to 0.0404%). The 11,654 hospital stays for VaD in 2017 represent 13.5% of mental organic disorders. Subtype analysis shows a decrease in hospital stays for multiple infarctions between 2007 and 2017 (-50%), an increase for subcortical or mixed VaD (+20%), acute onset VaD (+184%) and an increase in "other VaD" (+85%).

CONCLUSION

These data suggest a slight decrease in hospital stays for VaD, possibly related to better control of cardiovascular risk factors. They also suggest that the coding should be consistent with the evolution of diagnostic criteria.

Links Between Painting and Neurology: The Example of Dementia

Art is a system of human communication arising from symbolic cognition, conveying ideas, experiences, and feelings. The goal of this review is to describe the link between painting and dementia. Individuals with neurodegenerative diseases inevitably experience cognitive dysfunction that has the potential to limit and impair the artist's ability to realize their creative and expressive intentions through painting. The strategy to advance our understanding of the neural bases for art is to map locations and nature of neural damage to changes onto artistic production.

Review: Clinical, neuropathological and genetic features of Lewy body dementias

Lewy body dementias are the second most common neurodegenerative dementias after Alzheimer's disease and include dementia with Lewy bodies and Parkinson's disease dementia. They share similar clinical and neuropathological features but differ in the time of dementia and parkinsonism onset. Although Lewy bodies are their main pathological hallmark, several studies have shown the emerging importance of Alzheimer's disease pathology. Clinical amyloid-β imaging using Pittsburgh Compound B (PiB) supports neuropathological studies which found that amyloid-β pathology is more common in dementia with Lewy bodies than in Parkinson's disease dementia. Nevertheless, other co-occurring pathologies, such as cerebral amyloid angiopathy, TDP-43 pathology and synaptic pathology may also influence the development of neurodegeneration and dementia. Recent genetic studies demonstrated an important role of APOE genotype and other genes such as GBA and SNCA which seem to be involved in the pathophysiology of Lewy body dementias. The aim of this article is to review the main clinical, neuropathological and genetic aspects of dementia with Lewy bodies and Parkinson's disease dementia. This is particularly relevant as future management for these two conditions may differ.

Associations among Braak stage, Parkinsonian gait, cognition, and functional status in autopsy-confirmed dementia with Lewy bodies

OBJECTIVE

Compromised functional abilities in older adults with dementia with Lewy bodies (DLB) represent a significant burden to families and frequently lead to institutionalization. Contributing factors to this compromise are poorly understood.

METHODS

Using data collected at a first study visit, multiple regression modeling was used to examine the associations between Braak staged Alzheimer disease (AD) pathology, Apolipoprotein E (ApoE) status, Parkinsonian gait, cognition, and functional status from a cohort of 102 cases with an autopsy-confirmed diagnosis of dementia stemming from combined Lewy body and AD pathology.

RESULTS

On average, 60% of functional activities were compromised per case. Worse functional status was associated with older age at first study visit, compromised cognitive status, and Parkinsonian gait after controlling for gender, mental status, and other covariates. Worse cognitive status predicted worse functional status in both the low and high Braak groups.

CONCLUSIONS

Older persons with DLB presenting with moderately compromised cognition and Parkinsonian gait should be expected to have impaired functional abilities. Providing these patients with supportive environments may help them to remain independent for longer periods of time.

Evolution of Dementia Related to the Use of Alcohol in the French Nationwide Discharge Summary Database Between 2007 and 2017

BACKGROUND

The French nationwide exhaustive hospital discharge database (PMSI) is used for activity-based payment of hospital services. We hypothesized that the release of articles about alcohol and dementia could influence the identification of these diagnoses in PMSI.

METHODS

We analyzed temporal evolution of coding for dementia and other persistent or late-onset cognitive impairment (OPLOCI) due to alcohol and other psychoactive substances in the PMSI database from 2007 to 2017 (285 748 938 inpatient stays). These codings use the International Classification of Diseases, 10th revision (ICD-10).

RESULTS

The number of inpatient stays with dementia and OPLOCI due to alcohol increased from 34 to 1704 from 2007 to 2017. While the number of diagnosed dementias remained stable at around 400 from 2013, the number of OPLOCIs increased 10-fold from 2013 to 2017. This increase was not found with dementia or OPLOCI due to other psychoactive substances than alcohol.

CONCLUSION

Notoriety of a diagnosis in the literature seems to have an impact on the coding.

Associations of amygdala volume and shape with transactive response DNA-binding protein 43 (TDP-43) pathology in a community cohort of older adults

Transactive response DNA-binding protein 43 (TDP-43) pathology is common in old age and is strongly associated with cognitive decline and dementia above and beyond contributions from other neuropathologies. TDP-43 pathology in aging typically originates in the amygdala, a brain region also affected by other age-related neuropathologies such as Alzheimer's pathology. The purpose of this study was two-fold: to determine the independent effects of TDP-43 pathology on the volume, as well as shape, of the amygdala in a community cohort of older adults, and to determine the contribution of amygdala volume to the variance of the rate of cognitive decline after accounting for the contributions of neuropathologies and demographics. Cerebral hemispheres from 198 participants of the Rush Memory and Aging Project and the Religious Orders Study were imaged with MRI ex vivo and underwent neuropathologic examination. Measures of amygdala volume and shape were extracted for all participants. Regression models controlling for neuropathologies and demographics showed an independent negative association of TDP-43 with the volume of the amygdala. Shape analysis revealed a unique pattern of amygdala deformation associated with TDP-43 pathology. Finally, mixed-effects models showed that amygdala volume explained an additional portion of the variance of the rate of decline in global cognition, episodic memory, semantic memory, and perceptual speed, above and beyond what was explained by demographics and neuropathologies.

Risk of suicide and accidental deaths among elderly patients with cognitive impairment

Background

The leading causes of death among the elderly with cognitive impairment are unknown. This study aims to estimate the suicide and accidental death rates on the basis of a clinical case registry of patients diagnosed with cognitive impairment.

Methods

The target sample consisted of 10,169 patients diagnosed with dementia or mild cognitive impairment (MCI), who were evaluated at the Clinical Research Center for Dementia of Korea (CREDOS) from January 2005 to December 2013. Information about whether the patients had died from suicide or in any kind of accident by December 31, 2016, was obtained from the database of the National Statistical Office (NSO). The standardized mortality ratio (SMR) and Cox-regression analysis were performed for evaluating the risk of suicide and accidental death as identified by the ICD-10.

Results

The average of the Clinical Dementia Rating Scale (CDR) score (0.68 vs 0.93) was lower, and the age at the time of study registration (71.42 vs 75.68 years) was younger in the suicidal death group, as compared to the accidental death group. The overall SMR for accidental death in cognitively impaired patients (1.44, 95% CI 1.22–1.71) was significantly higher than the general population. Later onset (1.43, 95% CI 1.20–1.71) and older age (2.21, 95% CI 1.04–4.68) increased the risk of accidental death in cognitively impaired patients. According to the dementia subtypes, the SMR for accidental death was higher in both Alzheimer’s disease (1.72, 95% CI 1.36–2.14) and vascular dementia (2.14, 95% CI 1.27–3.38). Additionally, the SMR for accidental death showed an increasing tendency as the CDR score increased (mild 1.80, 95% CI 1.32–2.42, moderate 1.86, 95% CI 1.07–3.03, severe 3.32, 95% CI 1.08–7.76). Unemployment increased the risks of both suicide (3.71, 95% CI 1.54–8.95) and accidental death (2.09, 95% CI 1.20–3.63).

Conclusions

Among people with cognitive impairment, the risk of death by suicide did not increase, whereas that of accidental death increased significantly. Preventive strategies for premature mortality in those with cognitive impairment should be implemented from the early stages and should include careful evaluation of the individual risk factors for each type of death.

The center of olfactory bulb-seeded α-synucleinopathy is the limbic system and the ensuing pathology is higher in male than in female mice

At early disease stages, Lewy body disorders are characterized by limbic vs. brainstem α-synucleinopathy, but most preclinical studies have focused solely on the nigrostriatal pathway. Furthermore, male gender and advanced age are two major risk factors for this family of conditions, but their influence on the topographical extents of α-synucleinopathy and the degree of cell loss are uncertain. To fill these gaps, we infused α-synuclein fibrils in the olfactory bulb/anterior olfactory nucleus complex-one of the earliest and most frequently affected brain regions in Lewy body disorders-in 3-month-old female and male mice and in 11-month-old male mice. After 6 months, we observed that α-synucleinopathy did not expand significantly beyond the limbic connectome in the 9-month-old male and female mice or in the 17-month-old male mice. However, the 9-month-old male mice had developed greater α-synucleinopathy, smell impairment and cell loss than age-matched females. By 10.5 months post-infusion, fibril treatment hastened mortality in the 21.5-month-old males, but the inclusions remained centered in the limbic system in the survivors. Although fibril infusions reduced the number of cells expressing tyrosine hydroxylase in the substantia nigra of young males at 6 months post-infusion, this was not attributable to true cell death. Furthermore, mesencephalic α-synucleinopathy, if present, was centered in mesolimbic circuits (ventral tegmental area/accumbens) rather than within strict boundaries of the nigral pars compacta, which were defined here by tyrosine hydroxylase immunolabel. Nonprimate models cannot be expected to faithfully recapitulate human Lewy body disorders, but our murine model seems reasonably suited to (i) capture some aspects of Stage IIb of Lewy body disorders, which displays a heavier limbic than brainstem component compared to incipient Parkinson's disease; and (ii) leverage sex differences and the acceleration of mortality following induction of olfactory α-synucleinopathy.

Higher probability of prodromal Parkinson disease is related to lower cognitive performance

OBJECTIVE

Given the limited information on cognitive function before Parkinson disease (PD) clinical onset in the general population, we sought to assess prodromal PD (pPD) probability and relate it to detailed cognitive performance in a community cohort.

METHODS

In a population-based cohort of 1,629 dementia-free and PD-free participants ≥65 years of age in Greece, we assessed probability of pPD according to the International Parkinson and Movement Disorder Society's criteria. Clinical cognitive diagnoses (cognitively unimpaired, mild cognitive impairment [MCI], dementia) considering neuropsychological testing and functional status were assigned in consensus conferences. Cognitive performance in 5 cognitive domains was assessed by a detailed neuropsychological battery and summarized in the form of z scores. We investigated associations between pPD probability (and its individual constituents) and cognitive outcomes.

RESULTS

The median probability of pPD was 1.81% (0.2%-96.7%). Participants with MCI had higher probability of pPD compared to those with normal cognition (p < 0.001). Higher probability of pPD was related to lower performance in all cognitive domains (memory, language, executive, attention, and visuospatial function) (p < 0.001). Lower cognitive performance was further associated with certain nonmotor markers of pPD, such as daytime somnolence, depression, urinary dysfunction, constipation, and subthreshold parkinsonism (p < 0.001).

CONCLUSIONS

Higher probability of pPD was associated with lower cognitive performance in all domains and higher probability of MCI. This may reflect a widespread pathologic process although future studies are warranted to infer causality. These results suggest to clinicians that they should assess cognition early, and to researchers that they should further look into the possible mechanisms that may underlie this observation.

Clinical impact of [18F]flutemetamol PET among memory clinic patients with an unclear diagnosis

Purpose

To investigate the impact of amyloid PET with [¹⁸F]flutemetamol on diagnosis and treatment management in a cohort of patients attending a tertiary memory clinic in whom, despite extensive cognitive assessment including neuropsychological testing, structural imaging, CSF biomarker analysis and in some cases [¹⁸F]FDG PET, the diagnosis remained unclear.

Methods

The study population consisted of 207 patients with a clinical diagnosis prior to [¹⁸F]flutemetamol PET including mild cognitive impairment (MCI; n = 131), Alzheimer’s disease (AD; n = 41), non-AD (n = 10), dementia not otherwise specified (dementia NOS; n = 20) and subjective cognitive decline (SCD; n = 5).

Results

Amyloid positivity was found in 53% of MCI, 68% of AD, 20% of non-AD, 20% of dementia NOS, and 60% of SCD patients. [¹⁸F]Flutemetamol PET led, overall, to a change in diagnosis in 92 of the 207 patients (44%). A high percentage of patients with a change in diagnosis was observed in the MCI group (n = 67, 51%) and in the dementia NOS group (n = 11; 55%), followed by the non-AD and AD (30% and 20%, respectively). A significant increase in cholinesterase inhibitor treatment was observed after [¹⁸F]flutemetamol PET (+218%, 34 patients before and 108 patients after).

Conclusion

The present study lends support to the clinical value of amyloid PET in patients with an uncertain diagnosis in the tertiary memory clinic setting.

Abnormalities of Resting State Cortical EEG Rhythms in Subjects with Mild Cognitive Impairment Due to Alzheimer's and Lewy Body Diseases

The present study tested the hypothesis that cortical sources of resting state eyes-closed electroencephalographic (rsEEG) rhythms reveal different abnormalities in cortical neural synchronization in groups of patients with mild cognitive impairment due to Alzheimer's disease (ADMCI) and dementia with Lewy bodies (DLBMCI) as compared to cognitively normal elderly (Nold) subjects. Clinical and rsEEG data in 30 ADMCI, 23 DLBMCI, and 30 Nold subjects were available in an international archive. Age, gender, and education were carefully matched in the three groups. The Mini-Mental State Evaluation (MMSE) score was matched between the ADMCI and DLBMCI groups. Individual alpha frequency peak (IAF) was used to determine the delta, theta, alpha1, alpha2, and alpha3 frequency band ranges. Fixed beta1, beta2, and gamma bands were also considered. eLORETA estimated the rsEEG cortical sources. Receiver operating characteristic curve (ROCC) classified these sources across individuals. Compared to Nold, IAF showed marked slowing in DLBMCI and moderate in ADMCI. Furthermore, the posterior alpha 2 and alpha 3 source activities were more abnormal in the ADMCI than the DLBMCI group, while widespread delta source activities were more abnormal in the DLBMCI than the ADMCI group. The posterior delta and alpha sources correlated with the MMSE score and correctly classified the Nold and MCI individuals (area under the ROCC >0.85). In conclusion, the ADMCI and DLBMCI patients showed different features of cortical neural synchronization at delta and alpha frequencies underpinning brain arousal and vigilance in the quiet wakefulness. Future prospective cross-validation studies will have to test the clinical validity of these rsEEG markers.

Cognitive training for people with mild to moderate dementia

BACKGROUND

Cognitive impairment, a defining feature of dementia, plays an important role in the compromised functional independence that characterises the condition. Cognitive training (CT) is an approach that uses guided practice on structured tasks with the direct aim of improving or maintaining cognitive abilities.

OBJECTIVES

• To assess effects of CT on cognitive and non-cognitive outcomes for people with mild to moderate dementia and their caregivers.• To compare effects of CT with those of other non-pharmacological interventions, including cognitive stimulation or rehabilitation, for people with mild to moderate dementia and their caregivers.• To identify and explore factors related to intervention and trial design that may be associated with the efficacy of CT for people with mild to moderate dementia and their caregivers.

SEARCH METHODS

We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialised Register, on 5 July 2018. ALOIS contains records of clinical trials identified through monthly searches of several major healthcare databases and numerous trial registries and grey literature sources. In addition to this, we searched MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov, and the World Health Organization's trials portal, ICTRP, to ensure that searches were comprehensive and up-to-date.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that described interventions for people with mild to moderate dementia and compared CT versus a control or alternative intervention.

DATA COLLECTION AND ANALYSIS

We extracted relevant data from published manuscripts and through contact with trial authors if required. We assessed risk of bias using the Cochrane 'Risk of bias' tool. We divided comparison conditions into active or passive control conditions and alternative treatments. We used a large number of measures and data to evaluate 19 outcomes at end of treatment, as well as 16 outcomes at follow-up in the medium term; we pooled this information in meta-analyses. We calculated pooled estimates of treatment effect using a random-effects model, and we estimated statistical heterogeneity using a standard Chi² statistic. We graded the evidence using GradePro.

MAIN RESULTS

The 33 included trials were published between 1988 and 2018 and were conducted in 12 countries; most were unregistered, parallel-group, single-site RCTs, with samples ranging from 12 to 653 participants. Interventions were between two and 104 weeks long. We classified most experimental interventions as 'straight CT', but we classified some as 'augmented CT', and about two-thirds as multi-domain interventions. Researchers investigated 18 passive and 13 active control conditions, along with 15 alternative treatment conditions, including occupational therapy, mindfulness, reminiscence therapy, and others.The methodological quality of studies varied, but we rated nearly all studies as having high or unclear risk of selection bias due to lack of allocation concealment, and high or unclear risk of performance bias due to lack of blinding of participants and personnel.We used data from 32 studies in the meta-analysis of at least one outcome. Relative to a control condition, we found moderate-quality evidence showing a small to moderate effect of CT on our first primary outcome, composite measure of global cognition at end of treatment (standardised mean difference (SMD) 0.42, 95% confidence interval (CI) 0.23 to 0.62), and high-quality evidence showing a moderate effect on the secondary outcome of verbal semantic fluency (SMD 0.52, 95% CI 0.23 to 0.81) at end of treatment, with these gains retained in the medium term (3 to 12 months post treatment). In relation to many other outcomes, including our second primary outcome of clinical disease severity in the medium term, the quality of evidence was very low, so we were unable to determine whether CT was associated with any meaningful gains.When compared with an alternative treatment, we found that CT may have little to no effect on our first primary outcome of global cognition at end of treatment (SMD 0.21, 95% CI -0.23 to 0.64), but the quality of evidence was low. No evidence was available to assess our second primary outcome of clinical disease severity in the medium term. We found moderate-quality evidence showing that CT was associated with improved mood of the caregiver at end of treatment, but this was based on a single trial. The quality of evidence in relation to many other outcomes at end of treatment and in the medium term was too low for us to determine whether CT was associated with any gains, but we are moderately confident that CT did not lead to any gains in mood, behavioural and psychological symptoms, or capacity to perform activities of daily living.

AUTHORS' CONCLUSIONS

Relative to a control intervention, but not to a variety of alternative treatments, CT is probably associated with small to moderate positive effects on global cognition and verbal semantic fluency at end of treatment, and these benefits appear to be maintained in the medium term. Our certainty in relation to many of these findings is low or very low. Future studies should take stronger measures to mitigate well-established risks of bias, and should provide long-term follow-up to improve our understanding of the extent to which observed gains are retained. Future trials should also focus on direct comparison of CT versus alternative treatments rather than passive or active control conditions.

Survival time and differences between dementia with Lewy bodies and Alzheimer's disease following diagnosis: A meta-analysis of longitudinal studies

OBJECTIVE

To synthesize the evidence across longitudinal studies comparing survival in dementia with Lewy bodies (DLB) and Alzheimer's disease (AD).

METHODS

We conducted a systematic review and meta-analysis of studies comparing survival in clinically diagnosed DLB to AD. Longitudinal cohort studies were identified through a systematic search of major electronic databases from inception to May 2018. A random effects meta-analysis was performed to calculate survival time and relative risk of death.

RESULTS

Overall, 11 studies were identified including 22,952 patients with dementia: 2029 with DLB (mean diagnosis age 76.3; 47% female) compared with 20,923 with AD (mean diagnosis age 77.2; 65.1% female). Average survival time in DLB from diagnosis was 4.11 years (SD ± 4.10) and in AD 5.66 (SD ± 5.32) years, equating to a 1.60 (95% CI: -2.44 to -0.77) years shorter survival in DLB (p < 0.01). Relative risk of death was increased by 1.35 (95%CI: 1.17-1.55) in DLB compared to AD (p < 0.01). Differences in survival were not explained by follow-up time, age at diagnosis, gender, or cognitive score.

CONCLUSIONS

There is consistent evidence for higher and earlier mortality in DLB compared to AD. This is important for all stakeholders and underlines the importance of expanding research into DLB.

Diffuse Lewy body disease

Diffuse Lewy body disease, also called dementia with Lewy bodies (DLB), is defined as progressive dementia and pathological Lewy bodies distributed in the central and autonomic nervous systems. The clinical features are dementia, cognitive fluctuations, visual hallucinations, parkinsonism, and REM sleep behavior disorder (RBD). Confirmatory techniques include dopamine transporter imaging, meta-iodobenzylguanidine (MIBG) myocardial scintigraphy, and polysomnography. The pathology finding in DLB is misfolded alpha-synuclein, the main component of Lewy bodies, propagating in the central nervous system. This may interrupt the acetylcholine pathway and activate an inflammatory response. Mutations of several genes have been found in patients with DLB, including SNCA, GBA, and APOE. The differential diagnosis of DLB and Parkinson's disease with dementia (PDD) is a debated issue. Clinical features distinguishing DLB from PDD include the timing of dementia and visual hallucinations, responses to dopaminergic agents and anti-psychotics, and imaging findings. As to the management of DLB, cholinesterase inhibitors are the Level-A recommendation for treating dementia in DLB patients and also are beneficial for treating visual hallucinations and psychotic symptoms. Dopamine agonists have the risk of inducing psychotic symptoms, while levodopa should be used carefully for motor symptoms. Melatonin and clonazepam are effective in controlling RBD. Several other treatment methods are undergoing trials, including pimavanserine, nilotinib, psychological interventions, and behavior therapy.

Impact of physical activity in vascular cognitive impairment (AFIVASC): study protocol for a randomised controlled trial

BACKGROUND

Cognitive impairment and cerebrovascular pathology are both frequent with ageing. Cognitive impairment due to vascular pathology of the brain, termed vascular cognitive impairment (VCI), is one of the most frequent causes of cognitive impairment in elderly subjects. Thus far, VCI has no specific pharmacological treatment. Recent observational studies have suggested a protective effect of physical activity in cognition, but adequate randomised controlled trials (RCT) are lacking.

METHODS

AFIVASC is a multi-centre randomised controlled trial, with a 6-month intervention treatment and an additional follow-up of 6 months, that aims to estimate the impact of 6 months of moderate intensity physical activity on cognition (the primary outcome) at 6 and 12 months in subjects with VCI. Participants are community dwellers with criteria for VCI without dementia or who have had previous stroke or transient ischaemic attack (TIA). Patients may be self-referred or referred from a medical appointment. After confirming the inclusion criteria, a run-in period of 1 month is conducted to access adherence; only after that are subjects randomly assigned (using a computerised program blinded to clinical details) to two groups (intervention group and best practice usual care group). The intervention consists of three physical activity sessions of 60 min each (two supervised and one unsupervised) per week. The primary outcome is measured by the presence or absence of decline in cognitive status. Secondary outcomes include changes in neuro-cognitive measures, quality of life, and functional and motor status. Primary and secondary outcomes are evaluated at 6 and 12 months by investigators blinded to both intervention and randomisation. A required sample size of 280 subjects was estimated. Statistical analyses will include regression analysis with repeated measures. The study was approved by the Ethics Committee for Health of Centro Hospitalar de Lisboa Norte (ref. no. 1063/13) and by the Ethics Committee for Health of Centro Hospitalar do Porto CHP (ref. no. 2016.055(049-DEFI/048-CES)).

DISCUSSION

We aim to show whether or not moderate physical activity has a beneficial impact on cognition, quality of life, motor, and functional status in people with vascular cognitive impairment, and to generate new insights on the applicability of implementing physical activity in this specific population.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03578614 July 6, 2018.

Validation of the Rowland Universal Dementia Assessment Scale (RUDAS) in a multicultural sample across five Western European countries: diagnostic accuracy and normative data

ABSTRACTBackground:With increasing cultural diversity and growing elderly immigrant populations in Western European countries, the availability of brief cognitive screening instruments adequate for assessment of dementia in people from diverse backgrounds becomes increasingly important. The aim of the present study was to investigate diagnostic accuracy of the Rowland Universal Dementia Assessment Scale (RUDAS) in a multicultural sample and to calculate normative data as a basis for demographic adjustment of RUDAS scores.

METHODS

The study was a prospective international cross-sectional multi-center study. Receiver operating characteristic curve analysis was used to examine diagnostic accuracy. Regression analysis was used to assess the impact of demographic variables.

RESULTS

Data was collected from 341 cognitively intact participants and 80 people with dementia with a wide age- and educational range. Of the 421 included participants, 239 (57%) had immigrant background. The RUDAS had high diagnostic accuracy with an area under the curve (AUC) of 0.93. The optimal cut-off score was &lt;25 (sensitivity 0.80, specificity 0.90). Regression analysis revealed that RUDAS scores were mainly affected by education and were unrelated to data collection site and immigrant status. Education-adjusted normative data was calculated as a basis for education adjustment of RUDAS scores. Applying education-adjusted RUDAS scores slightly but significantly improved diagnostic accuracy with an AUC of 0.95.

CONCLUSION

We found the RUDAS to have excellent diagnostic properties in our multicultural sample. However, we suggest that RUDAS scores should be adjusted for education to increase diagnostic accuracy and that the choice of cut-off score should be considered based on the clinical context and expected base rate of dementia.

Corticobasal syndrome with visual hallucinations and probable REM-sleep behavior disorder: an autopsied case report of a patient with CBD and LBD pathology

Corticobasal syndrome and dementia with Lewy bodies are clinical presentations with unique and overlapping features but distinct pathological substrates. We report the case of an 80 year-old man who presented with apraxia, rigidity, slowness, right arm myoclonus, a 10-year history of probable REM-sleep behavior disorder, and later developed visual hallucinations. At autopsy, he had pathological features of corticobasal degeneration, and Lewy body disease confined to the brainstem. This report highlights the importance of considering co-existing pathologies when a clinical presentation defies categorization, and demonstrates that salient features of dementia with Lewy bodies may result from pathology limited to the brainstem.

The Impact of APOE ɛ4 in Alzheimer's Disease Differs According to Age

We evaluated how the impact of apolipoprotein E4 (APOE4) differs according to age in Alzheimer's disease (AD) patients. We recruited 846 AD patients and 815 cognitively normal controls and categorized into three groups with respect to their age (<65, 65-74, and ≥75 years). We evaluated the risk of AD in APOE4 carriers and compared cortical thickness and cognitive function according to APOE4 status in each age group. At the point of this study, in young (<65 years) AD, APOE4 noncarriers had the most severe frontal and perisylvian atrophy, while in old (≥75 years) AD, APOE4 carriers had the most severe medial temporal atrophy. In AD under 75 years, APOE4 noncarriers and heterozygotes showed worse performance in language, visuospatial, and frontal function compared to homozygotes, while, in old (≥75 years) AD, APOE4 homozygotes showed worse performance in memory compared to noncarriers. As the detrimental effects of APOE4 seen in older AD patients were not found in younger AD patients, we suggest that some unrevealed factors are associated with cortical atrophy and non-amnestic cognitive dysfunction in young AD with APOE4 noncarriers.

Dementia with Lewy bodies: an update and outlook

Dementia with Lewy bodies (DLB) is an age-associated neurodegenerative disorder producing progressive cognitive decline that interferes with normal life and daily activities. Neuropathologically, DLB is characterised by the accumulation of aggregated α-synuclein protein in Lewy bodies and Lewy neurites, similar to Parkinson’s disease (PD). Extrapyramidal motor features characteristic of PD, are common in DLB patients, but are not essential for the clinical diagnosis of DLB. Since many PD patients develop dementia as disease progresses, there has been controversy about the separation of DLB from PD dementia (PDD) and consensus reports have put forward guidelines to assist clinicians in the identification and management of both syndromes. Here, we present basic concepts and definitions, based on our current understanding, that should guide the community to address open questions that will, hopefully, lead us towards improved diagnosis and novel therapeutic strategies for DLB and other synucleinopathies.

The Impact of Cerebral Amyloid Angiopathy in Various Neurodegenerative Dementia Syndromes: A Neuropathological Study

Purpose

The Boston criteria for cerebral amyloid angiopathy (CAA) have to be confirmed by postmortem examination. The present study investigates the incidence and the cerebrovascular impact of the severity of CAA in various neurodegenerative dementia diseases.

Material and Methods

208 patients underwent an autopsy. They consisted of 92 brains with Alzheimer's disease (AD), 46 with frontotemporal lobar degeneration (FTLD), 24 with progressive supranuclear palsy (PSP), 21 with Lewy body dementia (LBD), 5 with corticobasal degeneration (CBD), and 20 controls. In addition to the macroscopic examination, a whole coronal section of a cerebral hemisphere, at the level of the mamillary body, was taken for semiquantitative microscopic evaluation of the small cerebrovascular lesions.

Results

CAA is present in 2/3% of the AD brains of which half of them have a severe form, grade 3. Only the latter displays more cerebrovascular lesions. CAA is present in 45% of the LBD brains. Cortical microinfarcts are only more frequent in the CAA grade 3 group. In LBD additional AD pathology is present in 41% of the CAA grade 0, 83% in grade 1-2, and 100% in grade 3. In PSP only 21% had CAA grade 1-2. In FTLD, CBD, and normal controls no CAA pathology is observed.

Conclusions

The present study shows that CAA is most frequently associated to AD but that only the severe form displays more cerebrovascular lesions. LBD is the second most frequent disease associated to CAA with a clear correlation between the incidence of the associated AD features and the increasing severity of the CAA. In PSP only 21% display mild CAA features. PSP, tau-FTLD, and CBD are part of the Pick complex diseases, who are known to have a favourable vascular profile which can explain their low incidence of cerebrovascular lesions, in contrast to AD and LBD brains.

Validation of a European Cross-Cultural Neuropsychological Test Battery (CNTB) for evaluation of dementia

BACKGROUND

The aims of this study were to establish the diagnostic accuracy of the European Cross-Cultural Neuropsychological Test Battery (CNTB) for dementia in different ethnic populations in Western Europe, to examine its ability to differentiate cognitive impairment profiles for dementia subtypes, and to assess the impact of demographic variables on diagnostic properties.

METHODS

The study was a Western European cross-sectional multi-center study. A total of 66 patients with dementia and 118 cognitively intact participants were included across six memory clinics; 93 had ethnic minority background and 91 had ethnic majority background. Tests in the CNTB cover global cognitive function, memory, language, executive functions, and visuospatial functions.

RESULTS

Significant differences with moderate to large effect sizes were present between patients with dementia and control participants on all CNTB measures. Area under the curves (AUC) ranged from .62 to .99 with a mean AUC across all measures of .83. Comparison of ethnic minority and majority groups generally revealed higher sensitivity in the minority group but no significant difference in the mean AUC's across all measures (.84 vs78, P = .42). Comparison of impairment profiles for patients with Alzheimer's disease (AD) and non-AD dementia revealed that AD patients were significantly more impaired on the memory domain, whereas patients with non-AD dementia were more impaired on the executive functions domain.

CONCLUSIONS

The CNTB was found to have promising cross-cultural diagnostic properties for evaluation of dementia in the targeted minority and majority populations and could represent a valid cross-cultural alternative to other well-established neuropsychological test batteries when assessing patients from these populations.

Cingulate cortex in Parkinson's disease

Once a diagnosis of Parkinson's disease (PD) has been made, even in its earliest prodromal form of subjective memory impairment, cognitive impairment has begun and involves anterior cingulate cortex (ACC). While the Braak staging scheme showed mid- to later-stage PD progression from cingulate allocortex adjacent to the corpus callosum and progressing into its neocortical moieties, the last decade has produced substantial information on the role of cingulate cortex in multiple symptoms, not just global measures of cognition. Voxel-based morphometry has been used in many studies of mild cognitive impairment (MCI) in PD to show reduced thickness in ACC and posterior cingulate cortex (PCC). Regional cerebral blood flow is altered in association with verbal IQ in all the PCC and anterior midcingulate cortex and executive impairments in ACC. Diffusion tensor imaging shows reduced fractional anisotropy throughout the entire cingulum bundle. Amnestic MCI is associated with reduced dopamine-2 receptor binding in ACC and, even in cognitively normal PD cases, dopaminergic pathways in ACC are impaired early in association with executive and language functions. The cholinergic system also has substantial changes in nicotinic and muscarinic receptor binding, and therapy with donepezil improves Mini-Mental State Exam scores and metabolism in pACC and dPCC. Cingulate cortex is also engaged in two critical symptoms: apathy and visual hallucinations. Finally, one can be optimistic that cingulate cortex will play an important role in developing new biomarkers of early PD. These methods have already been shown to be useful in cingulate cortex and include magnetic resonance spectroscopy, next-generation gene expression, and the new α-synuclein proximity ligation assay that specifically recognizes α-synuclein oligomers. Thus the future is bright for developing multivariate, multimodal biomarkers that include cingulate cortex.

The heart of PD: Lewy body diseases as neurocardiologic disorders

This review provides an update about cardiac sympathetic denervation in Lewy body diseases. The family of Lewy body diseases includes Parkinson's disease (PD), pure autonomic failure (PAF), and dementia with Lewy bodies (DLB). All three feature intra-neuronal cytoplasmic deposits of the protein, alpha-synuclein. Multiple system atrophy (MSA), the parkinsonian form of which can be difficult to distinguish from PD with orthostatic hypotension, involves glial cytoplasmic inclusions that contain alpha-synuclein. By now there is compelling neuroimaging, neuropathologic, and neurochemical evidence for cardiac sympathetic denervation in Lewy body diseases. In addition to denervation, there is decreased storage of catecholamines in the residual terminals. The degeneration develops in a centripetal, retrograde, "dying back" sequence. Across synucleinopathies the putamen and cardiac catecholaminergic lesions seem to occur independently of each other, whereas non-motor aspects of PD (e.g., anosmia, dementia, REM behavior disorder, OH) are associated with each other and with cardiac sympathetic denervation. Cardiac sympathetic denervation can be caused by synucleinopathy in inherited PD. According to the catecholaldehyde hypothesis, 3,4-dihydroxyphenylacetaldehyde (DOPAL), an intermediary metabolite of dopamine, causes or contributes to the death of catecholamine neurons, especially by interacting with proteins such as alpha-synuclein. DOPAL oxidizes spontaneously to DOPAL-quinone, which probably converts alpha-synuclein to its toxic oligomeric form. Decreasing DOPAL production and oxidation might slow the neurodegenerative process. Tracking cardiac sympathetic innervation over time could be the basis for a proof of principle experimental therapeutics trial targeting DOPAL.

Aripiprazole for the treatment of psychotic symptoms in patients with dementia with Lewy bodies: a case series

PURPOSE

The core features of dementia with Lewy bodies (DLB) are cognitive fluctuations, visual hallucinations, and parkinsonian symptoms. Although there have been several reports on the efficacy of treatments for psychotic symptoms in patients with DLB, little is known regarding the treatment effects of aripiprazole. The aim of this study was to evaluate the efficacy and safety of aripiprazole for the treatment of psychotic symptoms in patients with DLB.

PATIENTS AND METHODS

We employed a 10-week, open-label study design with 11 patients who met the criteria for DLB. The patients had previously experienced persistent or intermittent delusions, hallucinations, or both for at least 1 month. Aripiprazole was initiated at a low dose (3 or 6 mg/day) and titrated to higher doses at 2-week intervals or more rapidly, as needed. The Neuropsychiatric Inventory (NPI), Brief Psychiatric Rating Scale (BPRS), and Clinical Global Impression-Severity (CGI-S) were administered at baseline and 1, 2, 4, 8, and 10 weeks later. The Simpson-Angus Scale (SAS), Clinical Dementia Rating (CDR), and Mini-Mental State Examination (MMSE) Scale were evaluated at baseline and at week 10. The NPI, CGI-S, and BPRS scores were compared between the baseline and each assessment point and between each assessment point and the one before assessment point. The SAS, CDR, and MMSE scores were compared between the baseline and the end point.

RESULTS

The mean NPI and BPRS scores improved until the fourth week; they significantly decreased at each assessment point compared to the previous one. Afterward, improvements slowed and continued without significant decrease. The median SAS scores significantly decreased at the end point compared to the baseline (P<0.05). The median MMSE score was higher at the end point than at the baseline (P<0.05).

CONCLUSION

This study showed that aripiprazole may be effective and well tolerated for the treatment of psychotic symptoms in patients with DLB.

Chemosensory dysfunction in neurodegenerative diseases

A number of neurodegenerative diseases are accompanied by disordered smell function. The degree of dysfunction can vary among different diseases, such that olfactory testing can aid in differentiating, for example, Alzheimer's disease (AD) from major affective disorder and Parkinson's disease (PD) from progressive supranuclear palsy. Unfortunately, altered smell function often goes unrecognized by patients and physicians alike until formal testing is undertaken. Such testing uniquely probes brain regions not commonly examined in physical examinations and can identify, in some cases, patients who are already in the "preclinical" stage of disease. Awareness of this fact is one reason why the Quality Standards Committee of the American Academy of Neurology has designated smell dysfunction as one of the key diagnostic criteria for PD. The same recommendation has been made by the Movement Disorder Society for both the diagnosis of PD and identification of prodromal PD. Similar suggestions are proposed to include olfactory dysfunction as an additional research criterion for the diagnosis of AD. Although taste impairment, i.e., altered sweet, sour, bitter, salty, and umami perception, has also been demonstrated in some disorders, taste has received much less scientific attention than smell. In this review, we assess what is known about the smell and taste disorders of a wide range of neurodegenerative diseases and describe studies seeking to understand their pathologic underpinnings.

Association of brain heptachlor epoxide and other organochlorine compounds with lewy pathology

BACKGROUND

Organochlorine pesticides are associated with an increased risk of Parkinson's disease. A preliminary analysis from the Honolulu-Asia Aging Study suggested that heptachlor epoxide, a metabolite from an organochlorine pesticide extensively used in Hawaii, may be especially important. This was a cross sectional analysis to evaluate the association of heptachlor epoxide and other organochlorine compounds with Lewy pathology in an expanded survey of brain organochlorine residues from the longitudinal Honolulu-Asia Aging Study.

METHODS

Organochlorines were measured in frozen occipital or temporal lobes in 705 brains using gas chromatography with mass spectrometry. Lewy pathology was identified using hematoxylin and eosin- and α-synuclein immunochemistry-stained sections from multiple brain regions.

RESULTS

The prevalence of Lewy pathology was nearly doubled in the presence versus the absence of heptachlor epoxide (30.1% versus 16.3%, P < 0.001). Although associations with other compounds were weaker, hexachlorobenzene (P = 0.003) and α-chlordane (P = 0.007) were also related to Lewy pathology. Most of the latter associations, however, were a result of confounding from heptachlor epoxide. Neither compound was significantly related to Lewy pathology after adjustment for heptachlor epoxide. In contrast, the association of heptachlor epoxide with Lewy pathology remained significant after adjustments for hexachlorobenzene (P = 0.013) or α-chlordane (P = 0.005). Findings were unchanged after removal of cases of PD and adjustment for age and other characteristics.

CONCLUSIONS

Organochlorine pesticides are associated with the presence of Lewy pathology in the brain, even after exclusion of PD cases. Although most of the association is through heptachlor epoxide, the role of other organochlorine compounds is in need of clarification. © 2018 International Parkinson and Movement Disorder Society.

Prevalence of Depression, Anxiety and PTSD in People with Dementia: a Systematic Review and Meta-Analysis

There appears to be a link between depression/anxiety/PTSD and dementia, although the evidence is incomplete and the reason is unclear. Mental illness may cause dementia or may be prodromal or comorbid with dementia, or dementia may trigger a relapse of symptoms in individuals with a history of mental illness. This study examined the link between depression/anxiety/PTSD and dementia by evaluating the prevalence of these disorders in people with dementia, relative to their healthy peers. Existing meta-analyses have examined the prevalence of clinically-significant depression and anxiety in Alzheimer's disease (AD), and depression in frontotemporal dementia (FTD), but have not considered vascular dementia (VaD), dementia with Lewy bodies (DLB), PTSD, or anxiety in FTD. The current meta-analysis compared the prevalence of clinically-significant depression, anxiety and PTSD in the four most common types of dementia (AD, VaD, DLB, FTD) and in unspecified dementia to that of healthy controls (PROSPERO number: CRD42017082086). PubMed, EMBASE, PsycINFO and CINAHL database searches identified 120 eligible studies. Prevalence rates were calculated for depression and anxiety in AD, VaD, DLB, FTD, unspecified dementia, and controls. PTSD data were only available for unspecified dementia. Subgroup analyses indicated that depression, but not anxiety, was more prevalent in people with dementia compared to controls; however, the anxiety analyses were probably under-powered. The results support a link between depression and dementia; however, the link between anxiety or PTSD and dementia remains unclear due to insufficient data. Longitudinal data is now needed to clarify whether depression/anxiety/PTSD may be risk factors for dementia.

Episodic recognition memory and the hippocampus in Parkinson's disease: A review

Parkinson's disease is a progressive neurodegenerative disorder of aging. The hallmark pathophysiology includes the development of neuronal Lewy bodies in the substantia nigra of the midbrain with subsequent loss of dopaminergic neurons. These neuronal losses lead to the characteristic motor symptoms of bradykinesia, rigidity, and rest tremor. In addition to these cardinal motor symptoms patients with PD experience a wide range of non-motor symptoms, the most important being cognitive impairments that in many circumstances lead to dementia. People with PD experience a wide range of cognitive impairments; in this review we will focus on memory impairment in PD and specifically episodic memory, which are memories of day-to-day events of life. Importantly, these memory impairments severely impact the lives of patients and caregivers alike. Traditionally episodic memory is considered to be markedly dependent on the hippocampus; therefore, it is important to understand the exact nature of PD episodic memory deficits in relation to hippocampal function and dysfunction. In this review, we discuss an aspect of episodic memory called recognition memory and its subcomponents called recollection and familiarity. Recognition memory is believed to be impaired in PD; thus, we discuss what aspects of the hippocampus are expected to be deficient in function as they relate to these recognition memory impairments. In addition to the hippocampus as a whole, we will discuss the role of hippocampal subfields in recognition memory impairments.

Mass synaptometry: High-dimensional multi parametric assay for single synapses

BACKGROUND

Synaptic alterations, especially presynaptic changes, are cardinal features of neurodegenerative diseases and strongly correlate with cognitive decline.

NEW METHOD

We report "Mass Synaptometry" for the high-dimensional analysis of individual human synaptosomes, enriched nerve terminals from brain. This method was adapted from cytometry by time-of-flight mass spectrometry (CyTOF), which is commonly used for single-cell analysis of immune and blood cells.

RESULT

Here we overcome challenges for single synapse analysis by optimizing synaptosome preparations, generating a 'SynTOF panel,' recalibrating acquisition settings, and applying computational analyses. Through the analysis of 390,000 individual synaptosomes, we also provide proof-of principle validation by characterizing changes in synaptic diversity in Lewy Body Disease (LBD), Alzheimer's disease and normal brain.

COMPARISON WITH EXISTING METHOD(S)

Current imaging methods to study synapses in humans are capable of analyzing a limited number of synapses, and conventional flow cytometric techniques are typically restricted to fewer than 6 parameters. Our method allows for the simultaneous detection of 34 parameters from tens of thousands of individual synapses.

CONCLUSION

We applied Mass Synaptometry to analyze 34 parameters simultaneously on more than 390,000 synaptosomes from 13 human brain samples. This new approach revealed regional and disease-specific changes in synaptic phenotypes, including validation of this method with the expected changes in the molecular composition of striatal dopaminergic synapses in Lewy body disease and Alzheimer's disease. Mass synaptometry enables highly parallel molecular profiling of individual synaptic terminals.

Clinical-Neuropathological Correlations of Alzheimer's Disease and Related Dementias in Latino Volunteers

Clinical, neuropsychological, and neurological procedures used to diagnose Alzheimer's disease (AD) and related dementias were largely developed and validated in well-educated, non-Latino, English-speaking populations. Sociocultural and genetic differences in Latinos might influence the accuracy of clinical diagnosis of AD and other dementias. We aim to compare the accuracy of the clinical diagnosis of AD and related dementias in Latinos with the corresponding neuropathological diagnosis. From the UCSD Alzheimer's Disease Research Center longitudinal cohort, we selected all Latino participants who had autopsy neuropathological studies from 1991 to 2017. Participants underwent annual neurological clinical evaluations, standard neuropsychological tests, neuroimaging, and genotyping of Apolipoprotein E. We calculated the sensitivity and specificity of the clinical diagnosis of AD against the primary pathological diagnosis. Of the 34 participants with a primary neuropathological diagnosis of AD, 33 (97.1%) were correctly clinically diagnosed as having AD at the last clinical evaluation, and 1 was incorrectly diagnosed with dementia with Lewy bodies. Of the 19 participants without a primary neuropathological diagnosis of AD, 8 were incorrectly clinically diagnosed with probable AD at the last clinic evaluation. The clinical diagnosis of AD at the last clinical evaluation had 97.1% sensitivity and 57.9% specificity for autopsy-verified AD. In this Latino cohort, clinicians predicted AD pathological findings with high sensitivity but moderate specificity. Tangle-only dementia was the most common misdiagnosis. Our study suggests that current procedures and instruments to clinically determine AD in Latinos have high sensitivity compared with neuropathology, but specificity needs to be improved.

Prevalence of amyloid-β pathology in distinct variants of primary progressive aphasia

OBJECTIVE

To estimate the prevalence of amyloid positivity, defined by positron emission tomography (PET)/cerebrospinal fluid (CSF) biomarkers and/or neuropathological examination, in primary progressive aphasia (PPA) variants.

METHODS

We conducted a meta-analysis with individual participant data from 1,251 patients diagnosed with PPA (including logopenic [lvPPA, n = 443], nonfluent [nfvPPA, n = 333], semantic [svPPA, n = 401], and mixed/unclassifiable [n = 74] variants of PPA) from 36 centers, with a measure of amyloid-β pathology (CSF [n = 600], PET [n = 366], and/or autopsy [n = 378]) available. The estimated prevalence of amyloid positivity according to PPA variant, age, and apolipoprotein E (ApoE) ε4 status was determined using generalized estimating equation models.

RESULTS

Amyloid-β positivity was more prevalent in lvPPA (86%) than in nfvPPA (20%) or svPPA (16%; p < 0.001). Prevalence of amyloid-β positivity increased with age in nfvPPA (from 10% at age 50 years to 27% at age 80 years, p < 0.01) and svPPA (from 6% at age 50 years to 32% at age 80 years, p < 0.001), but not in lvPPA (p = 0.94). Across PPA variants, ApoE ε4 carriers were more often amyloid-β positive (58.0%) than noncarriers (35.0%, p < 0.001). Autopsy data revealed Alzheimer disease pathology as the most common pathologic diagnosis in lvPPA (76%), frontotemporal lobar degeneration-TDP-43 in svPPA (80%), and frontotemporal lobar degeneration-TDP-43/tau in nfvPPA (64%).

INTERPRETATION

This study shows that the current PPA classification system helps to predict underlying pathology across different cohorts and clinical settings, and suggests that age and ApoE genotype should be considered when interpreting amyloid-β biomarkers in PPA patients. Ann Neurol 2018;84:737-748.

123I-MIBG myocardial scintigraphy for the diagnosis of DLB: a multicentre 3-year follow-up study

BACKGROUND AND PURPOSE

We previously reported the usefulness of iodine-123 metaiodobenzylguanidine (¹²³I-MIBG) myocardial scintigraphy for differentiation of dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) in a cross-sectional multicentre study. The aim of this study was, by using reassessed diagnosis after 3-year follow-up, to evaluate the diagnostic accuracy of ¹²³I-MIBG scintigraphy in differentiation of probable DLB from probable AD.

METHODS

We undertook 3-year follow-up of 133 patients with probable or possible DLB or probable AD who had undergone ¹²³I-MIBG myocardial scintigraphy at baseline. An independent consensus panel made final diagnosis at 3-year follow-up. Based on the final diagnosis, we re-evaluated the diagnostic accuracy of ¹²³I-MIBG scintigraphy performed at baseline.

RESULTS

Sixty-five patients completed 3-year follow-up assessment. The final diagnoses were probable DLB (n=30), possible DLB (n=3) and probably AD (n=31), and depression (n=1). With a receiver operating characteristic curve analysis of heart-to-mediastinum (H/M) ratios for differentiating probable DLB from probable AD, the sensitivity/specificity were 0.77/0.94 for early images using 2.51 as the threshold of early H/M ratio, and 0.77/0.97 for delayed images using 2.20 as the threshold of delayed H/M ratio. Five of six patients who were diagnosed with possible DLB at baseline and with probable DLB at follow-up had low H/M ratio at baseline.

CONCLUSIONS

Our follow-up study confirmed high correlation between abnormal cardiac sympathetic activity evaluated with ¹²³I-MIBG myocardial scintigraphy at baseline and the clinical diagnosis of probable DLB at 3-year follow-up. Its diagnostic usefulness in early stage of DLB was suggested.

TRIAL REGISTRATION NUMBER

UMIN00003419.

Is transcranial sonography useful for diagnosing Parkinson's disease in clinical practice?

OBJECTIVE

Transcranial sonography (TCS) is an emerging ancillary examination for diagnosing Parkinson's disease (PD).

OBJECTIVE

To evaluate TCS features in patients with PD and its mimics, and establish their accuracy in predicting the final clinical diagnosis after follow-up.

METHODS

We retrospectively studied 85 patients with an initial clinical suspicion of PD, atypical parkinsonism or essential tremor, all of whom underwent TCS. Two specialists reviewed the follow-up clinical visit records and determined the final clinical diagnosis. The accuracy analysis of the TCS was determined using Bayesian statistical methods.

RESULTS

The finding of substantia nigra hyperechogenicity (> 20 mm2) showed high sensitivity (93.4%) and specificity (86.6%). The positive likelihood ratio showed 6.93-fold greater odds for diagnosing PD than an alternative condition when this finding was present.

CONCLUSIONS

This study revealed the practical usefulness of TCS in differentiating PD from its prevalent mimics when the clinical diagnosis was initially unclear.

Impact of monomeric, oligomeric and fibrillar alpha-synuclein on astrocyte reactivity and toxicity to neurons

Synucleinopathies are a group of neurodegenerative disorders characterized by the presence of aggregated and fibrillar forms of alpha-synuclein (α-syn). Here, we analyze the effect of different species of α-syn, including monomeric, oligomeric and fibrillar forms of the protein, on rat astrocytes. Astrocytes treated with these distinct forms of α-syn showed an increase in long and thin processes and glial fibrillary acidic protein expression, indicating cell activation, high levels of intracellular oxidants and increased expression of cytokines. Moreover, astrocytes incubated with the different species induced hippocampal neuronal death in co-culture, and cytotoxicity was particularly enhanced by exposure to fibrillar α-syn. Further exploration of the mechanisms behind astrocyte activation and cytotoxicity revealed differences between the assessed α-syn species. Only oligomers induced mitochondrial dysfunction in astrocytes and significantly increased extracellular hydrogen peroxide production by these cells. Besides, TNF-α and IL-1β (interleukin 1β) expression presented different kinetics and levels depending on which species induced the response. Our data suggest that α-syn species (monomeric, oligomeric and fibrillar) induce astrocyte activation that can lead to neuronal death. Nevertheless, the tested α-syn species act through different preferential mechanisms and potency. All together these results help to understand the effect of α-syn species on astrocyte function and their potential impact on the pathogenesis of Parkinson's disease and related α-synucleinopathies.

Cognition, Olfaction and Uric Acid in Early de novo Parkinson's Disease

Objective

Cognitive impairment is one of the nonmotor symptoms in Parkinson’s disease (PD), and olfactory dysfunction is used as a marker to detect premotor stages of PD. Serum uric acid (sUA) levels have been found to be a risk factor for PD. Our objective in this study was to examine whether sUA levels are associated with cognitive changes and olfactory dysfunction in early de novo PD patients.

Methods

The study participants included 196 de novo PD patients. We assessed cognitive function by the Korean versions of the Mini-Mental State Examination and the Montreal Cognitive Assessment and assessed olfactory function by the Korean version of the Sniffin’ Sticks test.

Results

The mean sUA level was 4.7 mg/dL and was significantly lower in women than in men. Cognitive scores were lower in women, suggesting that sUA levels were related to cognitive function. The olfactory functions were not related to sUA level but were clearly associated with cognitive scores. Olfactory threshold, odor discrimination, and odor identification were all significantly related to cognitive scores.

Conclusion

We conclude that lower sUA levels were associated with cognitive impairment, not olfactory dysfunction, in de novo PD patients. This finding suggests that UA is neuroprotective as an antioxidant in the cognitive function of PD patients.

Unveiling the olfactory proteostatic disarrangement in Parkinson's disease by proteome-wide profiling

Olfactory dysfunction is one of the earliest features in Lewy-type alpha-synucleinopathies (LTSs) such as Parkinson's disease (PD). However, the underlying molecular mechanisms associated to smell impairment are poorly understood. Applying mass spectrometry-based quantitative proteomics in postmortem olfactory bulbs across limbic, early-neocortical, and neocortical LTS stages of parkinsonian patients, a proteostasis impairment, was observed, identifying 268 differentially expressed proteins between controls and PD phenotypes. In addition, network-driven proteomics revealed a modulation in ERK1/2, MKK3/6, and PDK1/PKC signaling axes. Moreover, a cross-disease study of selected olfactory molecules in sporadic Alzheimer's disease (AD) cases revealed different protein derangements in the modulation of secretagogin (SCGN), calcyclin-binding protein (CACYBP), and glucosamine 6 phosphate isomerase 2 (GNPDA2) between PD and AD. An inverse correlation between GNPDA2 and α-synuclein protein levels was also reflected in PD cerebrospinal fluid. Interestingly, PD patients exhibited significantly lower serum GNPDA2 levels than controls (n = 82/group). Our study provides important avenues for understanding the olfactory bulb proteostasis imbalance in PD, deciphering mechanistic clues to the equivalent smell deficits observed in AD and PD pathologies.

A new visual rating scale for Ioflupane imaging in Lewy body disease

BACKGROUND

Dopaminergic loss on ¹²³I-Ioflupane brain imaging is a recognised biomarker for dementia with Lewy bodies. It is usually assessed using a visual rating scale developed for Parkinson's disease, which may not be optimal for dementia with Lewy bodies, as patterns of dopaminergic loss can be different.

OBJECTIVES

We aimed to develop a new visual rating scale for ¹²³I-Ioflupane brain images in Lewy body disease that encompasses appearances seen in dementia with Lewy bodies, and validate this against autopsy diagnosis.

METHODS

Four experienced observers developed and tested a new scale consisting of two metrics, reflecting overall loss and heterogeneity of loss. 66 subjects were used during development including clinical diagnoses of Alzheimer's disease (n = 14), Parkinson's disease (n = 9), Parkinson's disease dementia (n = 9), dementia with Lewy bodies (n = 15) and normal controls (n = 19). The scale was then tested on an independent group of 46 subjects with autopsy confirmed diagnosis: Alzheimer's disease (n = 11), Parkinson's disease (n = 3), Parkinson's disease dementia (n = 15), dementia with Lewy bodies (n = 12), normal controls (n = 4) and Frontotemporal dementia (n = 1).

RESULTS

In the autopsy validation the sensitivity and specificity of the new scale for Lewy body disease was 97% and 100% respectively, compared with the standard scale which had the same sensitivity (97%), but lower specificity (80%). The new scale had excellent inter rater reliability (intra-class correlation coefficient 0.93).

CONCLUSION

A new robust and reliable rating scale is described that straightforwardly captures the visual appearance of ¹²³I-Ioflupane brain images. It demonstrated high accuracy in autopsy confirmed cases and offers advantages over the existing visual rating scale.

Cognitive composite score association with Alzheimer's disease plaque and tangle pathology

BACKGROUND

Cognitive composite scores are used as the primary outcome measures for Alzheimer's disease (AD) prevention trials; however, the extent to which these composite measures correlate with AD pathology has not been fully investigated. Since many on-going AD prevention studies are testing therapies that target either amyloid or tau, we sought to establish an association between a cognitive composite score and the underlying pathology of AD.

METHODS

Data from 192 older deceased and autopsied persons from the Rush Religious Order Study were used in this study. All participants were classified at their initial evaluations with a clinical diagnosis of no cognitive impairment (NCI). Of these individuals, 105 remained NCI at the time of their death while the remaining 87 progressed to mild cognitive impairment (MCI) or AD. A cognitive composite score composed of eight cognitive tests was used as the outcome measure. Individuals were classified into groups based on Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropathological diagnosis and Braak stage.

RESULTS

The rate of annualized composite score decline was significantly greater for the high CERAD (p < 0.001, d = 0.56) and Braak (p < 0.001, d = 0.55) groups compared with the low CERAD and Braak groups, respectively. Mixed-model repeated measure (MMRM) analyses revealed a significantly greater difference in composite score change from baseline for the high CERAD group relative to the low CERAD group after 5 years (Δ = -2.74, 95% confidence interval (CI) -5.01 to -0.47; p = 0.02). A similar analysis between low and high Braak stage groups found no significant difference in change from baseline (Δ = -0.69, 95% CI -3.03 to 1.66; p = 0.56).

CONCLUSIONS

These data provide evidence that decreased cognitive composite scores were significantly associated with increased AD pathology and provide support for the use of cognitive composite scores in AD prevention trials.

Seasonal plasticity of cognition and related biological measures in adults with and without Alzheimer disease: Analysis of multiple cohorts

BACKGROUND

There are few data concerning the association between season and cognition and its neurobiological correlates in older persons-effects with important translational and therapeutic implications for the diagnosis and treatment of Alzheimer disease (AD). We aimed to measure these effects.

METHODS AND FINDINGS

We analyzed data from 3,353 participants from 3 observational community-based cohort studies of older persons (the Rush Memory and Aging Project [MAP], the Religious Orders Study [ROS], and the Minority Aging Research Study [MARS]) and 2 observational memory-clinic-based cohort studies (Centre de Neurologie Cognitive [CNC] study at Lariboisière Hospital and the Sunnybrook Dementia Study [SDS]). We performed neuropsychological testing and, in subsets of participants, evaluated cerebrospinal fluid AD biomarkers, standardized structured autopsy measures, and/or prefrontal cortex gene expression by RNA sequencing. We examined the association between season and these variables using nested multiple linear and logistic regression models. There was a robust association between season and cognition that was replicated in multiple cohorts (amplitude = 0.14 SD [a measure of the magnitude of seasonal variation relative to overall variability; 95% CI 0.07-0.23], p = 0.007, in the combined MAP, ROS, and MARS cohorts; amplitude = 0.50 SD [95% CI 0.07-0.66], p = 0.017, in the SDS cohort). Average composite global cognitive function was higher in the summer and fall compared to winter and spring, with the difference equivalent in cognitive effect to 4.8 years' difference in age (95% CI 2.1-8.4, p = 0.002). Further, the odds of meeting criteria for mild cognitive impairment or dementia were higher in the winter and spring (odds ratio 1.31 [95% CI 1.10-1.57], p = 0.003). These results were robust against multiple potential confounders including depressive symptoms, sleep, physical activity, and thyroid status and persisted in cases with AD pathology. Moreover, season had a marked effect on cerebrospinal fluid Aβ 42 level (amplitude 0.30 SD [95% CI 0.10-0.64], p = 0.003), which peaked in the summer, and on the brain expression of 4 cognition-associated modules of co-expressed genes (m6: amplitude = 0.44 SD [95% CI 0.21-0.65], p = 0.0021; m13: amplitude = 0.46 SD [95% CI 0.27-0.76], p = 0.0009; m109: amplitude = 0.43 SD [95% CI 0.24-0.67], p = 0.0021; and m122: amplitude 0.46 SD [95% CI 0.20-0.71], p = 0.0012), which were in phase or anti-phase to the rhythms of cognition and which were in turn associated with binding sites for several seasonally rhythmic transcription factors including BCL11A, CTCF, EGR1, MEF2C, and THAP1. Limitations include the evaluation of each participant or sample once per annual cycle, reliance on self-report for measurement of environmental and behavioral factors, and potentially limited generalizability to individuals in equatorial regions or in the southern hemisphere.

CONCLUSIONS

Season has a clinically significant association with cognition and its neurobiological correlates in older adults with and without AD pathology. There may be value in increasing dementia-related clinical resources in the winter and early spring, when symptoms are likely to be most pronounced. Moreover, the persistence of robust seasonal plasticity in cognition and its neurobiological correlates, even in the context of concomitant AD pathology, suggests that targeting environmental or behavioral drivers of seasonal cognitive plasticity, or the key transcription factors and genes identified in this study as potentially mediating these effects, may allow us to substantially improve cognition in adults with and without AD.