Affiliations: [a] Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden | [b] Department of Psychology, University of Gothenburg, Gothenburg, Sweden
Correspondence:
[*]
Correspondence to: Sindre Rolstad, c/o Anders Wallin Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Wallinsgatan 6, plan 4B, 431 41 Mölndal, Sweden. Tel.: +46 703 162 916; Fax: +46 31 776 9055; E-mail: sindre.rolstad@neuro.gu.se.
Abstract: The aim of this study was to predict cognitive performance on the basis of the cerebrospinal fluid (CSF) biomarkers total tau (T-tau) and amyloid-β42 (Aβ42) in controls and patients at various impairment levels. Previous studies have found an association of CSF T-tau levels with cognitive symptoms, but it has been difficult to relate Aβ to cognition, and it has thus been hypothesized that Aβ reaches a plateau level prior to cognitive symptoms. A comprehensive battery of neuropsychological tests was subjected to factor analysis to yield aggregated cognitive domains. Linear regression models were performed for the total sample of the Gothenburg MCI study (n = 435) and for each level of impairment. Aβ42 and T-tau accounted for a significant proportion of performance in all cognitive domains in the total sample. In controls (n = 60) and patients with subjective cognitive impairment (n = 105), Aβ42 predicted a significant proportion of semantic and working memory performance. For patients with mild cognitive impairment (n = 170), T-tau had the most pronounced impact across cognitive domains, and more specifically on episodic memory, visuospatial, and speed/executive performance. For patients with dementia (n = 100), the most pronounced impacts of Aβ42 were found in episodic memory and visuospatial functioning, while T-tau was substantially associated with episodic memory. Our results suggest that cognition is related to CSF biomarkers regardless of impairment level. Aβ42 is associated with cognitive functions from a potentially early to a later disease phase, and T-tau is more indicative of performance in a later disease phase.
