Associations of plasma neurofilament light protein levels with cognitive functions and brain structure parameters. (31st December 2021)

• Record Type: Journal Article
• Authors: Coors, Annabell; Boenniger, Meta M.; Santos, Marina; Koch, Alexandra; Zeng, Weiyi; Ettinger, Ulrich; Aziz, N. Ahmad; Breteler, Monique M.B.
• Is Part Of: Alzheimer's & dementia. Volume 17(2021)Supplement 5
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-31
• Subjects: Alzheimer's disease -- Periodicals; Alzheimer Disease -- Periodicals; Dementia -- Periodicals; Démence; Maladie d'Alzheimer; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.83
• DOI: 10.1002/alz.055922
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Neurofilament light (NfL) protein level is considered a non‐specific marker of neurodegeneration. NfL levels have been associated with established, non‐blood based neurodegenerative markers, including cognitive performance and reduced brain volume. However, most studies were small (N<300), and compared levels in patients (MCI, Alzheimer's disease) with those in healthy controls. We investigated to what extent NfL levels are associated with cognitive performance and MRI measures of brain volume and microstructure, in a large non‐demented population‐based sample. Method: The analyses were based on 4, 578 participants (30‐95 years) of the Rhineland Study, a community‐based cohort study in Bonn, Germany. Plasma NfL levels were measured on the SIMOA platform. We assessed cognitive performance with tests for memory, processing speed, executive function and crystallized intelligence and an eye movement (EM) test battery. 3, 206 persons underwent structural and diffusion weighted MR imaging. Imaging outcomes included volumetric measures (total brain, grey matter, white matter, hippocampus); diffusion tensor measures (fractional anisotropy; mean, radial, and axial diffusivity); and neurite orientation dispersion and density imaging (NODDI) measures. We used multivariable regression models to assess the relation between NfL levels and cognitive performance and MRI measures with adjustment for possible confounders. Result: Across all participants, we found only negligibly small associations between NfL levels and cognitive performance, brain volumetric and diffusion tensor measures. However, age‐stratified analyses revealed that in age 40‐49 and from age 60 onwards higher NfL levels were associated with lower orientation dispersion index (ODI). In the 70‐ to 79‐year‐olds, higher NfL levels were additionally associated with higher prosaccade accuracy, higher mean, axial and radial diffusivity, higher extracellular and lower intracellular volume fraction and a lower neurite density index. In the 80+‐year‐olds, NfL levels were negatively associated with hippocampal and white matter volume and positively associated with fractional anisotropy and radial diffusivity. Conclusion: Higher NfL levels were associated with smaller hippocampal volume and diffusion tensor and NODDI measures in older subjects. In younger persons (up to age 70 years), NfL levels were only associated with ODI. This suggests that NfL level is a sensitive marker of subtle changes in brain microstructure, especially in old age.