Associations between subjective cognitive decline (SCD) diagnosis and severity with plasma tau and NfL levels using SIMOA technology: Biomarkers (non‐neuroimaging) / plasma/serum/urine biomarkers. (7th December 2020)

• Record Type: Journal Article
• Authors: Azad, Dishari Zaman; Debure, Ludovic; Vedvyas, Alok; Osorio, Ricardo S; Masurkar, Arjun V; Wisniewski, Thomas; Shao, Yongzhao
• Is Part Of: Alzheimer's & dementia. Volume 16(2020)Supplement 4
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-07
• 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.043886
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Subjective cognitive decline (SCD) is thought to be a preclinical stage of Alzheimer's disease (AD) and is based largely on subjective report data in the context of normal neuropsychological functioning. There is, however, an unclear relationship between SCD and potential plasma markers along the AD spectrum. Method: 213 older adults (53 cognitively normal, [NL], 52 SCD, 54 mild cognitive impairment [MCI] and 54 AD), mean age 74.9±9.6, completed the UDS 3.0 battery, the Global Deterioration Scale (GDS) and a blood draw. Plasma levels of Aβ40, Aβ42, neurofilament light (NfL) and tau were measured using ultra‐sensitive, single‐molecule array (SIMOA) technology. Result: Plasma NfL levels were high in MCI patients and higher still in those with AD over cognitively unimpaired people (NL and SCD) (F(2, 198) =22, p<.001) before and after correction for age, sex and apoE4 status. Both plasma tau and Aβ42 levels were higher in SCD over NL subjects (F(1, 95) =7.8 and F(1, 96) =6.5; both p<0.05). Importantly, plasma tau but not Aβ42, Aβ42/ Aβ40 ratio or NfL was correlated with self‐reported Cognitive Change Index (CCI) scores both in the overall sample (r154 =2.4, p<0.01) and in the NL and SCD only (r89 =2.15, p<0.5). Conclusion: Plasma NfL is a potential biomarker of cognitive decline to MCI and AD, while plasma tau may have higher discriminatory value in the preclinical stages of the disease and is associated with SCD.