Borelli, Wyllians Vendramini

Abstract Background Clinicians’ views on clinical readiness of Alzheimer's disease (AD) blood biomarkers (BBM) are not well understood. Method The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment Biofluid‐Based Biomarkers Professional Interest Area conducted a survey to elicit clinician opinions on AD BBM implementation, including contexts of use, assay selection, reporting and result interpretation. Result Clinician respondents ( n = 212) practiced in Europe (56%), North America (24%), Caribbean and Central or South America (11%) and other continents (9%). Most respondents were medical doctors (80%) practicing in secondary or tertiary care (88%) (Table 1). For 56% of respondents, CSF AD biomarkers or amyloid PET were accessible, but 48% agreed and 52% disagreed with implementation of AD BBM in any clinical context (Table 2). Respondents emphasized the need for data from diverse populations and educational resources to support test interpretation. Conclusion Surveyed clinicians generally agreed with published appropriate use recommendations but were divided on AD BBM readiness for clinical use.

Abstract Background The quantification of Neurofilament Light chain (NfL) in blood and cerebrospinal fluid (CSF) has proven valuable for diagnosing and prognosing various neurological disorders, including Alzheimer's disease, frontotemporal dementia, amyotrophic lateral sclerosis, parkinsonism, multiple sclerosis, and ischemic damage. However, there is considerable variability in clinical and laboratory practices between centers, primarily due to different contexts of use (COU), analytical methods, and the application of cutoffs or scales. Additionally, for the same biochemical profile, the interpretation and reporting of results may vary from one center to another, raising concerns about the commutability of the tests. To date, no consensus has been reached among laboratories to define the most appropriate use of cutoffs or conclusions/comments based on NfL profiles. Method This international project involves 38 laboratories across 18 countries, all specialized in the biochemical diagnosis of neurological disorders. Using a questionnaire, we obtained descriptions from each center regarding their COU, pre‐analytical and analytical protocols (including the biological fluid and methods used to quantify NfL). Through a consensus approach, we developed a harmonized strategy for the use and reporting of NfL results across different centres according to their respective COU. Results Among the centers, 63% quantified NfL in the CSF, 87% in blood and 53% in both fluids. COU were as follow: frontotemporal dementia (71%), Alzheimer disease (71%), multiple sclerosis (61%), amyotrophic lateral sclerosis (61%), psychiatric syndrome (45%), Creutzfeldt‐Jakob disease (32%), Parkinson disease (39%), peripheral neuropathy (29%), traumatic brain injury (21%), Huntington's disease (13%), amyloid transthyretin related (11%) and cardiac arrest (8%). Most of the centers define pathological cutoffs based on publications (50%) and take age into account for this purpose (42%). Reporting is mostly transmitted through numeric results (95%). Conclusion Harmonizing cutoffs, reporting, and interpretation across various clinical contexts will facilitate the incorporation of this biomarker into routine clinical practice.

Abstract INTRODUCTION Neurofilament light chain (NfL) quantification aids in diagnosing and predicting neurological disorders, but clinical and laboratory practices vary across centers. Differences in result interpretation and reporting further challenge test commutability. This study aimed to review the global analytical and post‐analytical methods used for NfL measurement in routine clinical practice across different contexts. METHODS We established an international working group (WG) and distributed a survey to its members to gather information on context of use (COU), (pre) analytical methods, cutoff usage, as well as the interpretation and reporting of NfL measurements. RESULTS Among the centers, 63% measured NfL in cerebrospinal fluid (CSF), 87% in blood, and 53% in both. COU was widespread, with 50% defining pathological cutoffs based on publications and 42% considering age. Reporting was primarily done through numeric results (95%). DISCUSSION Harmonizing cutoffs, reporting, and interpretation across various clinical contexts will facilitate the incorporation of this biomarker into routine clinical practice. Highlights Unique international overview of current analytical and post‐analytical methods for neurofilament light chain (NfL) measurement in routine clinical practice. Tailored sheets for each neurological application. Strategies to harmonize cutoffs, reporting, and interpretation of NfL's measurement.

Abstract INTRODUCTION Clinicians’ views on the clinical readiness of Alzheimer's disease (AD) blood biomarkers (BBMs) are not well understood. METHODS The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment Biofluid‐Based Biomarkers Professional Interest Area conducted a survey to elicit clinician opinions on AD BBM implementation, including contexts of use, assay selection, reporting, and result interpretation. RESULTS Clinician respondents ( n = 212) practiced in Europe (56%), North America (24%), the Caribbean and Central/South America (11%), and other continents (9%). Most respondents were medical doctors (80%) practicing in secondary or tertiary care (88%). For 56%, cerebrospinal fluid AD biomarkers or amyloid positron emission tomography were accessible, but 48% agreed and 52% disagreed with the implementation of AD BBMs in any clinical context. Respondents emphasized the need for data from diverse populations and educational resources to support test interpretation. DISCUSSION Surveyed clinicians generally agreed with published appropriate use recommendations but were divided on AD BBM readiness for clinical use. Highlights A survey of clinicians was conducted regarding clinical readiness of Alzheimer's disease (AD) blood biomarkers (BBMs). Views were split on AD BBM clinical readiness: 48% agreed, 52% disagreed. Most responders supported AD BBM use for treatment decisions. Most responders opposed AD BBM testing in asymptomatic individuals. Test performance data and educational materials to aid interpretation were of high importance.