Combination of Structural MRI and FDG-PET of the Brain Improves Diagnostic Accuracy in Newly Manifested Cognitive Impairment in Geriatric Inpatients

Article type: Research Article

Authors: Ritter, Kerstin^{a; *} | Lange, Catharina^b | Weygandt, Martin^a | Mäurer, Anja^c | Roberts, Anna^c | Estrella, Melanie^d | Suppa, Per^{b; e} | Spies, Lothar^e | Prasad, Vikas^b | Steffen, Ingo^b | Apostolova, Ivayla^f | Bittner, Daniel^g | Gövercin, Mehmet^d | Brenner, Winfried^b | Mende, Christine^h | Peters, Oliverⁱ | Seybold, Joachim^{c; j} | Fiebach, Jochen B.^k | Steinhagen-Thiessen, Elisabeth^l | Hampel, Harald^m | Haynes, John-Dylan^a | Buchert, Ralph^{b; *}

Affiliations: [a] Berlin Center for Advanced Neuroimaging, Bernstein Center for Computational Neuroscience, Charité - Universitätsmedizin Berlin, Berlin, Germany | [b] Department of Nuclear Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany | [c] Evangelisches Geriatriezentrum Berlin, Berlin, Germany | [d] Geriatric Research Group, Department of Geriatric Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany | [e] Jung Diagnostics GmbH, Hamburg, Germany | [f] Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Magdeburg, Germany | [g] Department of Neurology, University Hospital Magdeburg, Magdeburg, Germany | [h] Vivantes Ida Wolff Krankenhaus, Berlin, Germany | [i] Department of Psychiatry and Psychotherapy Charité Benjamin Franklin, Charité - Universitätsmedizin Berlin, Berlin, Germany | [j] Department of Internal Medicine/Infectious Diseases and Pulmonary Medicine, Charité - Universitätsmedizin Berlin, Germany | [k] Center for Stroke Research Berlin, Charité, Berlin, Germany | [l] Lipid Clinic at the Interdisciplinary Metabolism Center, Charité - Universitätsmedizin, Berlin, Germany | [m] AXA Research Fund & UPMC Chair, Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Institut de la Mémoire et de la Maladied’ Alzheimer (IM2A) & Institut du Cerveau et de la Moelleépinière (ICM), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, Paris, France

Correspondence: [*] Correspondence to: Kerstin Ritter, PhD and Ralph Buchert, PhD, Charitéplatz 1, 10117 Berlin, Germany. Tel.: +49 30 450 539364; Fax: +49 30 2093 6758; E-mail: [email protected] (K. Ritter); Tel.: +49 30 450 627059; Fax: +49 30 450 7527959; E-mail: [email protected] (R. Buchert).

Abstract: Background: The cause of cognitive impairment in acutely hospitalized geriatric patients is often unclear. The diagnostic process is challenging but important in order to treat potentially life-threatening etiologies or identify underlying neurodegenerative disease. Objective: To evaluate the add-on diagnostic value of structural and metabolic neuroimaging in newly manifested cognitive impairment in elderly geriatric inpatients. Methods: Eighty-one inpatients (55 females, 81.6±5.5 y) without history of cognitive complaints prior to hospitalization were recruited in 10 acute geriatrics clinics. Primary inclusion criterion was a clinical hypothesis of Alzheimer’s disease (AD), cerebrovascular disease (CVD), or mixed AD+CVD etiology (MD), which remained uncertain after standard diagnostic workup. Additional procedures performed after enrollment included detailed neuropsychological testing and structural MRI and FDG-PET of the brain. An interdisciplinary expert team established the most probable etiologic diagnosis (non-neurodegenerative, AD, CVD, or MD) integrating all available data. Automatic multimodal classification based on Random Undersampling Boosting was used for rater-independent assessment of the complementary contribution of the additional diagnostic procedures to the etiologic diagnosis. Results: Automatic 4-class classification based on all diagnostic routine standard procedures combined reproduced the etiologic expert diagnosis in 31% of the patients (p = 0.100, chance level 25%). Highest accuracy by a single modality was achieved by MRI or FDG-PET (both 45%, p≤0.001). Integration of all modalities resulted in 76% accuracy (p≤0.001). Conclusion: These results indicate substantial improvement of diagnostic accuracy in uncertain de novo cognitive impairment in acutely hospitalized geriatric patients with the integration of structural MRI and brain FDG-PET into the diagnostic process.

Keywords: Cognitive impairment, geriatric inpatients, magnetic resonance imaging, multimodal classification, positron emission tomography

DOI: 10.3233/JAD-160380

Journal: Journal of Alzheimer's Disease, vol. 54, no. 4, pp. 1319-1331, 2016