Low Subicular Volume as an Indicator of Dementia-Risk Susceptibility in Old Age
Sonja M. Kagerer, Clemens Schroeder, Jiri M.G. Van Bergen, Simon J. Schreiner, Rafael Meyer, Stefanie C. Steininger, Laetitia Vionnet, Anton Gietl, Valérie Treyer, Alfred Buck, Klaas P. Pruessmann, Christoph Höck, Paul G. Unschuld
Abstract
Introduction Hippocampal atrophy is an established Alzheimer’s Disease (AD) biomarker. Volume loss in specific subregions as measurable with ultra-high field magnetic resonance imaging (MRI) may reflect earliest pathological alterations. Methods Data from positron emission tomography (PET) for estimation of cortical amyloid β (Aβ) and high-resolution 7 Tesla T1 MRI for assessment of hippocampal subfield volumes were analyzed in 61 non-demented elderly individuals who were divided into risk-categories as defined by high levels of cortical Aβ and low performance in standardized episodic memory tasks. Results High cortical Aβ and low episodic memory interactively predicted subicular volume [ F (3,57) = 5.90, p = 0.018]. The combination of high cortical Aβ and low episodic memory was associated with significantly lower subicular volumes, when compared to participants with high episodic memory ( p = 0.004). Discussion Our results suggest that low subicular volume is linked to established indicators of AD risk, such as increased cortical Aβ and low episodic memory. Our data support subicular volume as a marker of dementia-risk susceptibility in old-aged non-demented persons.