Combination of Hippocampal Volume and Cerebrospinal Fluid Biomarkers Improves Predictive Value in Mild Cognitive Impairment

Abstract

Background: Mild cognitive impairment (MCI) is a heterogeneous condition, and the prognosis differs within the group. Recent findings suggest that hippocampal volumetry and CSF biomarkers can be used to predict which MCI patients have an underlying neurodegenerative disorder. Objective: To examine the combined predictive value of hippocampal volume and CSF levels of total tau (T-tau) and β-amyloid₄₂ (Aβ₄₂) in stable and converting MCI patients. The participants (n = 68) included patients with MCI at baseline and who converted to dementia by the time of the 2-year follow-up (n = 21), stable MCI patients (n = 21) and healthy controls (n = 26). Methods: The Göteborg MCI study is a clinically based longitudinal study with biannual clinical assessments. Hippocampal volumetry was performed manually, based on data from the 0.5-tesla MRI investigations at baseline. Baseline CSF levels of T-tau and Aβ₄₂ were measured using commercially available, enzyme-linked immunosorbent assays. Results: The converting MCI group had significantly smaller left hippocampi, lower CSF Aβ₄₂ and higher T-tau compared to both the stable MCI group and the healthy controls. Multivariate analysis revealed that a combination of the variables outperformed the prognostic ability of the separate variables. Conclusions: Hippocampal volumes supplement the prognostic accuracy of CSF Aβ₄₂ and T-tau in MCI.