Plasma neurofilament light chain as prognostic marker of cognitive decline in neurodegenerative diseases, a clinical setting study.

BACKGROUND: Analysis of selected research cohorts has highlighted an association between plasma neurofilament light (NfL) protein and cross-sectional cognitive impairment as well as longitudinal cognitive decline. However, the findings have yielded inconsistent results regarding its possible application in clinical practice. Despite its potential prognostic significance, the role of plasma NfL in daily clinical practice with unselected patients suffering from cognitive impairment remains largely unexplored. METHODS: This retrospective, cross-sectional and longitudinal monocentric study enrolled 320 patients with Alzheimer's disease ([AD], n = 158), dementia with Lewy body ([DLB], n = 30), frontotemporal dementia ([FTD], n = 32), non-neurodegenerative diseases ([NND], n = 59) or subjective cognitive decline ([SCD], n = 41). Plasma NfL levels were measured at baseline on the Simoa platform. AD, DLB, and FTD patients were also analyzed altogether as a 'degenerative conditions' subgroup, whereas SCD and NND were grouped as a 'non-degenerative conditions' subgroup. We assessed the relationship between plasma NfL levels and cross-sectional cognitive performance, including global cognition and six specific cognitive domains. A subset of 239 patients had follow-up mini-mental state examinations (MMSE) up to 60 months. Models were adjusted on age, education level, glomerular filtration rate and body mass index. RESULTS: In 320 patients, baseline plasma NfL levels were negatively associated with global cognition (ß=-1.28 (-1.81 ; -0.75) P < 0.001), memory (ß=-1.48 (-2.38 ; -0.59), P = 0.001), language (ß=-1.72(-2.49 ; -0.95) P < 0.001), praxis (ß=-2.02 (-2.91 ; -1.13) P < 0.001) and executive functions (ß=-0.81, P < 0.001). Across diagnosis, plasma NfL levels were negatively associated with cross-sectional global cognition in all but the SCD subgroup, specifically with executive functions and memory in AD (respectively ß=-0.71(-1.21 ; -0.211), P = 0.005 and ß=-1.29 (-2.17 ; -0.42), P = 0.004), and with attention in LBD (ß=-0.81(-1.16 ; -0.002), P = 0.03). Linear mixed-effects models showed that plasma NfL predicted MMSE decline in the global population (ßPlasmaNfLxTime=-0.15 (-0.26 ; -0.04), P = 0.006), as in the neurodegenerative condition subgroup (ßPlasmaNfLxTime=-0.21 (-0.37 ; - 0.06), P = 0.007), but not in non-neurodegenerative condition subgroup. CONCLUSION: In our clinical cohort, plasma NfL was associated with faster cognitive decline in neurodegenerative dementia, which corroborates data obtained in research cohorts. Yet, plasma NfL was not predictive of accelerated cognitive decline in individuals without neurodegeneration, suggesting its use as a neurodegeneration-specific predictive biomarker.

[P-glycoprotein activity in vivo in older adults: physiological, -pathophysiological and pharmacokinetic interplay at the blood-brain barrier]. / Activité de la p-glycoprotéine in vivo chez la personne âgée : intrications physiologique, physiopathologique et pharmacocinétique au niveau de la barrière hémato-encéphalique.

p-glycoprotein (P-gp) is an efflux transporter of xenobiotic and endogenous compounds across the blood-brain barrier (BBB). P-gp plays an essential role by limiting passage of these compounds into the brain tissue. It is susceptible to drug-drug interactions when interactors drugs are co-administrated. The efficiency of P-gp may be affected by the aging process and the development of neurodegenerative diseases. Studying this protein in older adults is therefore highly relevant for all these reasons. Understanding P-gp activity in vivo is essential when considering the physiological, pathophysiological, and pharmacokinetic perspectives, as these aspects seem to be interconnected to some extent. In vivo exploration in humans is based on neuroimaging techniques, which have been improving over the last years. The advancement of exploration and diagnostic tools is opening up new prospects for understanding P-gp activity at the BBB.

Plasma biomarkers of amyloid, tau, axonal, and neuroinflammation pathologies in dementia with Lewy bodies.

BACKGROUND: Increasing evidence supports the use of plasma biomarkers of amyloid, tau, neurodegeneration, and neuroinflammation for diagnosis of dementia. However, their performance for positive and differential diagnosis of dementia with Lewy bodies (DLB) in clinical settings is still uncertain. METHODS: We conducted a retrospective biomarker study in two tertiary memory centers, Paris Lariboisière and CM2RR Strasbourg, France, enrolling patients with DLB (n = 104), Alzheimer's disease (AD, n = 76), and neurological controls (NC, n = 27). Measured biomarkers included plasma Aß40/Aß42 ratio, p-tau181, NfL, and GFAP using SIMOA and plasma YKL-40 and sTREM2 using ELISA. DLB patients with available CSF analysis (n = 90) were stratified according to their CSF Aß profile. RESULTS: DLB patients displayed modified plasma Aß ratio, p-tau181, and GFAP levels compared with NC and modified plasma Aß ratio, p-tau181, GFAP, NfL, and sTREM2 levels compared with AD patients. Plasma p-tau181 best differentiated DLB from AD patients (ROC analysis, area under the curve [AUC] = 0.80) and NC (AUC = 0.78), and combining biomarkers did not improve diagnosis performance. Plasma p-tau181 was the best standalone biomarker to differentiate amyloid-positive from amyloid-negative DLB cases (AUC = 0.75) and was associated with cognitive status in the DLB group. Combining plasma Aß ratio, p-tau181 and NfL increased performance to identify amyloid copathology (AUC = 0.79). Principal component analysis identified different segregation patterns of biomarkers in the DLB and AD groups. CONCLUSIONS: Amyloid, tau, neurodegeneration and neuroinflammation plasma biomarkers are modified in DLB, albeit with moderate diagnosis performance. Plasma p-tau181 can contribute to identify Aß copathology in DLB.

[P-glycoprotein activity in vivo in older adults: physiological, pathophysiological and pharmacokinetic interplay at the blood-brain barrier]. / Activité de la p-glycoprotéine in vivo chez la personne âgée : intrications physiologique, physiopathologique et pharmacocinétique au niveau de la barrière hémato-encéphalique.

p-glycoprotein (P-gp) is an efflux transporter of xenobiotic and endogenous compounds across the blood-brain barrier (BBB). P-gp plays an essential role by limiting passage of these compounds into the brain tissue. It is susceptible to drug-drug interactions when interactors drugs are co-administrated. The efficiency of P-gp may be affected by the aging process and the development of neurodegenerative diseases. Studying this protein in older adults is therefore highly relevant for all these reasons. Understanding P-gp activity in vivo is essential when considering the physiological, pathophysiological, and pharmacokinetic perspectives, as these aspects seem to be interconnected to some extent. In vivo exploration in humans is based on neuroimaging techniques, which have been improving over the last years. The advancement of exploration and diagnostic tools is opening up new prospects for understanding P-gp activity at the BBB.

Psychosis in Neurodegenerative Dementias: A Systematic Comparative Review.

Background: Psychosis, characterized by delusions and/or hallucinations, is frequently observed during the progression of Alzheimer's disease (AD) and other neurodegenerative dementias (ND) (i.e., dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD)) and cause diagnostic and management difficulties. Objective: This review aims at presenting a concise and up-to-date overview of psychotic symptoms that occur in patients with ND with a comparative approach. Methods: A systematic review was conducted following the PRISMA guidelines. 98 original studies investigating psychosis phenotypes in neurodegenerative dementias were identified (40 cohort studies, 57 case reports). Results: Psychosis is a frequently observed phenomenon during the course of ND, with reported prevalence ranging from 22.5% to 54.1% in AD, 55.9% to 73.9% in DLB, and 18% to 42% in FTD. Throughout all stages of these diseases, noticeable patterns emerge depending on their underlying causes. Misidentification delusions (16.6-78.3%) and visual hallucinations (50-69.6%) are frequently observed in DLB, while paranoid ideas and somatic preoccupations seem to be particularly common in AD and FTD, (respectively 9.1-60.3% and 3.10-41.5%). Limited data were found regarding psychosis in the early stages of these disorders. Conclusions: Literature data suggest that different ND are associated with noticeable variations in psychotic phenotypes, reflecting disease-specific tendencies. Further studies focusing on the early stages of these disorders are necessary to enhance our understanding of early psychotic manifestations associated with ND and help in differential diagnosis issues.

The role of adiponectin in Alzheimer's disease: A translational review.

Adiponectin is an adipokine playing a central role in the regulation of energy homeostasis, carbohydrate and lipid metabolism, as well as immunomodulation. The relationship between Alzheimer's disease (AD) and body composition has highlighted the bidirectional crosstalk between AD's pathophysiology and metabolic disorders. This review aimed to report the current state of knowledge about cellular and molecular mechanisms linking adiponectin and AD, in preclinical studies. Then, we reviewed human studies to assess the relationship between adiponectin levels and AD diagnosis. We also examined the risk of incident AD regarding the participants' baseline adiponectin level, as well as the relationship of adiponectin and cognitive decline in patients with AD. We conducted a systematic review, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline, of studies published over the last decade on MEDLINE and Cochrane databases. Overall, we reviewed 34 original works about adiponectin in AD, including 11 preclinical studies, two both preclinical and human studies and 21 human studies. Preclinical studies brought convincing evidence for the neuroprotective role of adiponectin on several key mechanisms of AD. Human studies showed conflicting results regarding the relationship between AD and adiponectin levels, as well as regarding the cross-sectional association between cognitive function and adiponectin levels. Adiponectin did not appear as a predictor of incident AD, nor as a predictor of cognitive decline in patients with AD. Despite solid preclinical evidence suggesting the protective role of adiponectin in AD, inconsistent results in humans supports the need for further research.

Comparison of CSF and plasma NfL and pNfH for Alzheimer's disease diagnosis: a memory clinic study.

Plasma neurofilament light chain (NfL) is a promising biomarker of axonal damage for the diagnosis of neurodegenerative diseases. Phosphorylated neurofilament heavy chain (pNfH) has demonstrated its value in motor neuron diseases diagnosis, but has less been explored for dementia diagnosis. In a cross-sectional study, we compared cerebrospinal fluid (CSF) and plasma NfL and pNfH levels in n = 188 patients from Lariboisière Hospital, Paris, France, including AD patients at mild cognitive impairment stage (AD-MCI, n = 36) and dementia stage (n = 64), non-AD MCI (n = 38), non-AD dementia (n = 28) patients and control subjects (n = 22). Plasma NfL, plasma and CSF pNfH levels were measured using Simoa and CSF NfL using ELISA. The correlation between CSF and plasma levels was stronger for NfL than pNfH (rho = 0.77 and rho = 0.52, respectively). All neurofilament markers were increased in AD-MCI, AD dementia and non-AD dementia groups compared with controls. CSF NfL, CSF pNfH and plasma NfL showed high performance to discriminate AD at both MCI and dementia stages from control subjects [AUC (area under the curve) = 0.82-0.91]. Plasma pNfH displayed overall lower AUCs for discrimination between groups compared with CSF pNfH. Neurofilament markers showed similar moderate association with cognition. NfL levels displayed significant association with mediotemporal lobe atrophy and white matter lesions in the AD group. Our results suggest that CSF NfL and pNfH as well as plasma NfL levels display equivalent performance in both positive and differential AD diagnosis in memory clinic settings. In contrast to motoneuron disorders, plasma pNfH did not demonstrate added value as compared with plasma NfL.

[Assessment and impairment of cognitive functions]. / Évaluation et atteintes des fonctions cognitives.

Cognitive functions enable us to receive, select, store, transform, process and retrieve the information we receive from the outside world. These functions are controlled by different brain structures that interact with each other, enabling us to interact with and understand the world around us. In the course of aging or the onset of neurocognitive diseases, these functions may be impaired to a greater or lesser extent, giving rise to a considerable variety of neurocognitive impairment profiles. When a patient appears to be suffering from neurocognitive disorders, a thorough neuropsychological evaluation can help to characterize this impairment precisely, before guiding therapeutic management. It also contributes significantly to the etiological diagnosis of the disorder.

BPSD Patterns in Patients With Severe Neuropsychiatric Disturbances: Insight From the RECAGE Study.

OBJECTIVE: Behavioral and psychological symptoms of dementia (BPSD) profiles vary depending on etiology in patients with mild-to-moderate BPSD. It is not known if similar differences exist in patients with severe BPSD. METHODS: We analyzed data collected at baseline in 398 patients with severe BPSD (NPI ≥ 32) and defined diagnosis of dementia (Alzheimer's disease [AD] 297; frontotemporal dementia [FTD] 39; Lewy body disease/Parkinsonian dementia [LBD/PD] 31; and vascular dementia [VD] 31) included in the European multicenter cohort RECAGE. RESULTS: Mean total NPI was 52.11 (18.55). LBD/PD patients demonstrated more hallucinations, more anxiety and more delusions than patients with other dementia. FTD patients had less delusions and more disinhibition than patients with other neurodegenerative disorders. These profiles overlapped partially with those reported in the literature in patients with less severe symptoms. CONCLUSION: Patients with severe BPSD display different and specific profiles of neuropsychiatric symptoms depending on dementia etiology.

[Evaluation of the perspectives and experiences regarding lumbar puncture in cognitively impaired older adults over 70, their relatives and the care teams]. / Évaluation des représentations et du vécu liés à la ponction lombaire chez des patients âgés de plus de 70 ans atteints de troubles cognitifs, leurs accompagnants et les équipes soignantes.

INTRODUCTION: Lumbar puncture (LP) is an essential diagnostic procedure, which raises major concerns in older adults. Some patients may be denied LP because of the fear of complications in healthcare teams which are not familiar with the procedure. The objectives of our work were to analyze the perspectives and the experiences regarding scheduled LP in cognitively impaired older adults, as well as in their relatives, and the healthcare teams from geriatric day hospitals. METHODS: We conducted a qualitative, observational and multicentric study, based on semi-directive interviews of patients aged over 70 years with cognitive complaints undergoing a scheduled LP in a day hospital. Patients were interviewed before and after LP. Their relatives and the involved healthcare teams were also interviewed to analyze their expectations and perspectives regarding the procedure. The full interviews were transcribed and analyzed using interpretative phenomenological analysis. RESULTS: Ten patients (mean age 80.2 ± 7.2), five relatives and four healthcare teams were included. The goals and operating procedure of LP were poorly understood by several patients. Some individuals feared irreversible neurological consequences or LP-related pain, which was often overestimated with regards to the post-LP interviews. The patients' major expectation was to establish an accurate and early diagnosis of their cognitive disorder to provide optimal care plan. Relatives reported similar fears of major adverse events. They also expected an accurate diagnosis with biomarkers. The perspectives and experiences of the healthcare teams were heterogeneous, according to their level of practice of LP, but seemed in line with current scientific guidelines. CONCLUSION: This study highlighted the existence of false beliefs and poor knowledge regarding the LP procedure and its associated risks. The post-LP patients' feedbacks were better than their expectations, especially in day hospitals with solid experience in LP. Better patient information may be a key to improve our practice.

Prior participation as a standardized patient improves OSCE scores of third-year medical students: A pilot comparative study at Université Paris Cité Medical School.

OBJECTIVE: Objective structured clinical examinations (OSCE) are one of the main modalities of skills' assessment of medical students. We aimed to evaluate the educational value of the participation of third-year medical students in OSCE as standardized patients. METHODS: We conducted a pilot OSCE session where third-year students participated in sixth-year students' OSCE as standardized patients (cases). Their scores in their own subsequent OSCE exams were compared with third-year students who had not participated (controls). Students' perceptions (stress, preparedness, ease) regarding their OSCE were compared with self-administered questionnaires. RESULTS: A total of 42 students were included (9 cases and 33 controls). Median [IQR] overall score (out of 20 points) obtained by the cases was 17 [16.3-18] versus 14.5 [12.7-16.3] for controls (p < 0.001). Students' perception of their evaluation (difficulty, stress, communication) was not significantly different between cases and controls. Most cases agreed that their participation was beneficial in reducing their stress (67%), increasing their preparedness (78%) and improving their communication skills (100%). All cases agreed that this participation should be offered more widely. CONCLUSION: Students' participation in OSCE as standardized patients led to better performance on their own OSCE and were considered beneficial. This approach could be more broadly generalized to improve student performance.

Lumbar puncture training with healthcare simulation improves self-confidence and practical skills of French medical residents in geriatrics.

PURPOSE: To assess the skill level and self-confidence of medical residents in geriatrics with regard to conducting the lumbar puncture (LP) procedure and to study the potential benefits of training with simulation and virtual reality. METHODS: First, a questionnaire survey was conducted among all French residents in geriatrics in the Paris area to assess their knowledge and self-confidence regarding the practice of LP in older adults. Second, we set up a simulation LP training session combined with virtual reality (3D video) training for selected respondents of the first survey. Third, we performed post-simulation survey for the attendees of the simulation training. Finally, a follow-up survey was conducted to examine the change in self-confidence and the success rate in clinical practice. RESULTS: Fifty-five residents responded to the survey (response rate = 36.4%). The importance of mastering LP was fully recognized by the residents in geriatrics (95.3%), so most of them (94.5%) advocated for the need for additional practical training. Fourteen residents took part in the training (average rating = 4.7 on a 5-point scale). Simulation was regarded by 83% of the respondents as the most useful tool for their practice. We observed a significant pre/post-training mean improvement in self-estimated success of 20.6% (Wilcoxon matched-pairs signed-rank W = - 36, p = 0.008). The post-training success rate of the residents in real-life clinical practice was good (85.8%). CONCLUSION: Residents were aware of the importance of mastering LP and requested additional training. Simulation may represent a major driver to improve their self-confidence and practical skills.

Tinetti balance performance is associated with mortality in older adults with late-onset Parkinson's disease: a longitudinal study.

BACKGROUND: Parkinson's disease (PD) is associated with a 3-fold mortality risk, which is closely related to advancing age. Evidence is lacking regarding the factors associated with the risks of mortality or nursing-home (NH) admission, in elderly patients with PD. We aimed at identifying the clinical characteristics associated with these outcomes, in older community-dwelling patients with late-onset PD. METHODS: Retrospective, observational analysis of data from geriatric day hospital patients. Motor assessment included Unified Parkinson Disease Rating Scale (UPDRS) part III score, Tinetti Performance Oriented Mobility Assessment (POMA) balance and gait tests, and gait speed. Levodopa equivalent dose, comorbidity, cognitive performance, Activities of Daily Living performance were examined. Cox proportional hazards models were performed to identify the factors associated with mortality and NH admission rate (maximum follow-up time = 5 years). RESULTS: We included 98 patients, mean age 79.4 (SD = 5.3) of whom 18 (18.3%) died and 19 (19.4%) were admitted into NH, over a median follow-up of 4 years. In multivariate Cox models, poor balance on the Tinetti POMA scale (HR = 0.82 95%CI (0.66-0.96), p = .023) and older age (HR = 1.12 95%CI (1.01-1.25), p = .044) were the only variables significantly associated with increased mortality risk. A Tinetti balance score below 11/16 was associated with a 6.7 hazard for mortality (p = .006). No specific factor was associated with NH admissions. CONCLUSIONS: Age and the Tinetti POMA score were the only factors independently associated with mortality. The Tinetti POMA scale should be considered for balance assessment and as a screening tool for the most at-risk individuals, in this population.

Plasma Leptin Is Associated With Amyloid CSF Biomarkers and Alzheimer's Disease Diagnosis in Cognitively Impaired Patients.

BACKGROUND: Metabolic dysfunction and dysregulation of leptin signaling have been linked to Alzheimer's disease (AD)'s pathophysiology. The objectives of this study were to examine the associations between plasma leptin, cerebrospinal fluid (CSF), beta-amyloid (Aß), and tau biomarkers (AT[N] status) and with the stage of cognitive impairment. METHODS: Cross-sectional analysis of data from cognitively impaired patients from a tertiary memory clinic. Plasma leptin levels were compared according to the stage of cognitive impairment and biomarker profiles, using the AT(N) classification. Linear regression models were performed to examine the relationship between leptin and CSF biomarkers. Results were adjusted for age, gender, body mass index (BMI), and APOE ε4. In a subgroup of A+T+ individuals, we compared the 2-year evolution of Mini-Mental State Examination scores, according to the participants' tertile of plasma leptin levels. RESULTS: We included 1 036 participants (age 68.7 ± 9.1, females = 54.1%). A+T+ and A+T- patients had significantly lower plasma leptin levels than amyloid negative participants (p < .01). CSF Aß concentration was significantly associated with lower plasma leptin ß = -4.3 (1.5), p = .005 unadjusted; and ß = -3.4 (1.6), p = .03 after adjustment for age, female gender, BMI, and APOE ε4. Patients with major neurocognitive disorder due to AD had a difference of leptin of -7.3 ng/mL 95% confidence interval (CI; -11.8; -2.8), p = .0002, compared to individuals with other causes of cognitive impairment. Leptin was not associated with the slope of cognitive decline. CONCLUSION: Plasma leptin levels were associated with CSF Aß and with the diagnosis of AD confirmed by CSF biomarkers, suggesting a molecular interplay between leptin metabolism and brain amyloid deposition.

Plasma neurofilament light chain in memory clinic practice: Evidence from a real-life study.

OBJECTIVE: To explore the accuracy of plasma neurofilament light chain (NfL) as a biomarker for diagnosis and staging of cognitive impairment, in a large cohort with of previously diagnosed patients in clinical practice. METHODS: Retrospective, cross-sectional, monocentric study, from a tertiary memory clinic. Patients underwent cerebrospinal fluid core Alzheimer's disease (AD) biomarker evaluation using ELISA or Elecsys methods, and plasma NfL analysis using the single molecule array technology. The patients' biomarker data were examined for associations with: i/cognitive status ii/presence of neurodegenerative disease and iii/diagnostic groups. Associations between core CSF biomarkers and plasma NfL were determined. RESULTS: Participants (N = 558, mean age = 69.2 ± 8.8, 56.5% women) were diagnosed with AD (n = 274, considering dementia and MCI stages), frontotemporal dementia (FTD, n = 55), Lewy body disease (LBD, n = 40, considering MCI and dementia stages), other neurodegenerative diseases, n = 57 (e.g Supranuclear Palsy, Corticobasal syndrome), non-neurodegenerative cognitive impairment (NND, n = 79, e.g. vascular lesions, epilepsy or psychiatric disorders) or subjective cognitive impairment (SCI, n = 53). Mean plasma NfL (log, pg/mL) levels were higher in neurodegenerative than non-neurodegenerative disorders (1.35 ± 0.2 vs 1.16 ± 0.23, p < 0.001), higher in all diagnostic groups than in SCI (1.06 ± 0.23) p < 0.001), and associated with the stage of cognitive impairment (p < 0.001). The addition of plasma NfL to a clinical model (age, MMSE and APOE ε4 carriership) marginally improved the discrimination of degenerative from non-degenerative disorders in ROC analysis (AUC clinical model: 0.81, 95% CI = [0.77;0.85] AUC clinical model + plasma NfL: AUC = 0.83 95% CI = [0.78;0.87], delta Akaike information criterion = -11.7). DISCUSSION: Plasma NfL could help discrimination between degenerative and non-degenerative cognitive disorders, albeit not better than comprehensive clinical evaluation.

Cerebrospinal Fluid Alpha-Synuclein Improves the Differentiation between Dementia with Lewy Bodies and Alzheimer's Disease in Clinical Practice.

Background: Alpha-synuclein, abnormally aggregated in Dementia with Lewy Bodies (DLB), could represent a potential biomarker to improve the differentiation between DLB and Alzheimer's disease (AD). Our main objective was to compare Cerebrospinal Fluid (CSF) alpha-synuclein levels between patients with DLB, AD and Neurological Control (NC) individuals. Methods: In a monocentric retrospective study, we assessed CSF alpha-synuclein concentration with a validated ELISA kit (ADx EUROIMMUN) in patients with DLB, AD and NC from a tertiary memory clinic. Between-group comparisons were performed, and Receiver Operating Characteristic analysis was used to identify the best CSF alpha-synuclein threshold. We examined the associations between CSF alpha-synuclein, other core AD CSF biomarkers and brain MRI characteristics. Results: We included 127 participants (mean age: 69.3 ± 8.1, Men: 41.7%). CSF alpha-synuclein levels were significantly lower in DLB than in AD (1.28 ± 0.52 ng/mL vs. 2.26 ± 0.91 ng/mL, respectively, p < 0.001) without differences due to the stage of cognitive impairment. The best alpha-synuclein threshold was characterized by an Area Under the Curve = 0.85, Sensitivity = 82.0% and Specificity = 76.0%. CSF alpha-synuclein was associated with CSF AT(N) biomarkers positivity (p < 0.01) but not with hippocampal atrophy or white matter lesions. Conclusion: CSF Alpha-synuclein evaluation could help to early differentiate patients with DLB and AD in association with existing biomarkers.

Hypnosis for pain and anxiety management in cognitively impaired older adults undergoing scheduled lumbar punctures: a randomized controlled pilot study.

BACKGROUND: Core cerebrospinal fluid (CSF) amyloid and tau biomarker assessment has been recommended to refine the diagnostic accuracy of Alzheimer's disease. Lumbar punctures (LP) are invasive procedures that might induce anxiety and pain. The use of non-pharmacological techniques must be considered to reduce the patient's discomfort, in this setting. The objective of this study was to examine the efficacy of hypnosis on anxiety and pain associated with LP. METHODS: A monocentric interventional randomized-controlled pilot study is conducted in a university geriatric day hospital. Cognitively impaired patients aged over 70 were referred for scheduled LP for the diagnostic purpose (CSF biomarkers). The participants were randomly assigned either to a hypnosis intervention group or usual care. Pain and anxiety were both self-assessed by the patient and hetero-evaluated by the operator. RESULTS: We included 50 cognitively impaired elderly outpatients (women 54%, mean age 77.2 ± 5.0, mean Mini-Mental State Examination score 23.2 ± 3.5). Hypnosis was significantly associated with reduced self-assessed (p < 0.05) and hetero-assessed anxiety (p < 0.01). Hetero-evaluated pain was significantly lower in the hypnosis group (p < 0.05). The overall perception of hypnosis was safe, well-accepted, and feasible in all the participants of the intervention group with 68% perceiving the procedure as better or much better than expected. CONCLUSIONS: This pilot study suggested that hypnosis was feasible and may be used to reduce the symptoms of discomfort due to invasive procedures in older cognitively impaired patients. Our results also confirmed the overall good acceptance of LP in this population, despite the usual negative perception. TRIAL REGISTRATION: ClinicalTrials.gov NCT04368572. Registered on April 30, 2020.

A Pragmatic, Data-Driven Method to Determine Cutoffs for CSF Biomarkers of Alzheimer Disease Based on Validation Against PET Imaging.

BACKGROUND AND OBJECTIVES: To elaborate a new algorithm to establish a standardized method to define cutoffs for CSF biomarkers of Alzheimer disease (AD) by validating the algorithm against CSF classification derived from PET imaging. METHODS: Low and high levels of CSF phosphorylated tau were first identified to establish optimal cutoffs for CSF ß-amyloid (Aß) peptide biomarkers. These Aß cutoffs were then used to determine cutoffs for CSF tau and phosphorylated tau markers. We compared this algorithm to a reference method, based on tau and amyloid PET imaging status (ADNI study), and then applied the algorithm to 10 large clinical cohorts of patients. RESULTS: A total of 6,922 patients with CSF biomarker data were included (mean [SD] age: 70.6 [8.5] years, 51.0% women). In the ADNI study population (n = 497), the agreement between classification based on our algorithm and the one based on amyloid/tau PET imaging was high, with Cohen's kappa coefficient between 0.87 and 0.99. Applying the algorithm to 10 large cohorts of patients (n = 6,425), the proportion of persons with AD ranged from 25.9% to 43.5%. DISCUSSION: The proposed novel, pragmatic method to determine CSF biomarker cutoffs for AD does not require assessment of other biomarkers or assumptions concerning the clinical diagnosis of patients. Use of this standardized algorithm is likely to reduce heterogeneity in AD classification.