Amyloid-β positive individuals with subjective cognitive decline present increased CSF neurofilament light levels that relate to lower hippocampal volume

Abstract

Neurofilament light chain (NfL) is an axonal protein that when measured in cerebrospinal fluid (CSF) serves as a biomarker of neurodegeneration. We aimed at investigating the association among CSF NfL, presence of Subjective Cognitive Decline (SCD) and hippocampal volume, and how CSF amyloid-β (Aβ) modifies these associations. We included 278 cognitively unimpaired participants from the Alfa+ cohort (78 SCD and 200 Controls). Linear models accounting for covariates (age, gender, and mood) were used to test the association between CSF NfL and SCD status, and between CSF NfL and bilateral hippocampal volumes. Interactions with Aβ were also explored. Individuals with SCD had higher CSF NfL and lower CSF Aβ42/40 than Controls. There was a significant interaction between SCD and CSF-Aβ42/40 levels. Stratified analyses showed a significant association between SCD and NfL only in Aβ+ individuals. Higher CSF NfL was significantly associated with lower hippocampal volume specifically in Aβ+ individuals with SCD. The presence of SCD in Aβ+ individuals may represent an early symptom in the Alzheimer's continuum related to incipient neurodegeneration. ; The research leading to these results has received funding from "la Caixa" Foundation (LCF/PR/GN17/1030 0 0 04) and the Alzheimer's Association and an international anonymous char ity foundation through the TriBEKa Imaging Platform project (TriBEKa-17-519007). Additional support has been received from the Universities and Research Secretariat, Ministry of Business and Knowledge of the Catalan Government under the grant no. 2017-SGR-892. MS-C received funding from the European Union's Horizon 2020 Research and Innovation Program under the Marie Sklodowska-Curie action grant agreement No 752310, and currently receives funding from the Spanish Ministry of Science, Innovation and Universities (Juan de la Cierva Programme grant IJC2018-037478-I ). EMA-U is supported by the Spanish Ministry of Science, Innovation and Universities - Spanish State Research Agency ( RYC2018-026053-I ) and is recipient of the Alzheimer's Association Research Grant ( AARC 2019-AARG 6 446 41). OG-R is supported by the Spanish Ministry of Science, Innovation and Universities ( FJCI-2017-33437 ). JDG holds a 'Ramón y Cajal' fellowship ( RYC-2013-13054 ). NV-T is funded by a post-doctoral grant, Juan de la Cierva Programme ( FJC2018-038085-I ), Ministry of Science and Innovation–Spanish State Research Agency. ASV is the recipient of an Instituto de Salud Carlos III Miguel Servet II fellowship ( CP II 17/0 0 029 ). HZ is a Wallenberg Scholar supported by grants from the Swedish Research Council (# 2018-02532 ), the European Research Council (# 681712 ), Swedish State Support for Clinical Research (# ALFGBG-720931 ), the Alzheimer Drug Discovery Foundation (ADDF), USA (# 201809-2016862 ), and the UK Dementia Research Institute at UCL. KB is supported by the Alzheimer Drug Discovery Foundation (ADDF), USA (# RDAPB-201809-2016615 ), the Swedish Alzheimer Foundation (# AF-742881 ), Hjärnfonden, Sweden (# FO2017-0243 ), the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (# ALFGBG-715986 ), and European Union Joint Program for Neurodegenerative Disorders (JPND2019-466-236 )