Clinical Characteristic in Primary Progressive Aphasia in Relation to Alzheimer’s Disease Biomarkers

Article type: Research Article

Authors: Kang, Sung Hoon^{a; b; c; 1} | Cho, Hanna^{d; 1} | Shin, Jiho^{a; b} | Kim, Hang-Rai^{a; b; e} | Noh, Young^f | Kim, Eun-Joo^g | Lyoo, Chul Hyoung^d | Jang, Hyemin^{a; b} | Kim, Hee Jin^{a; b} | Koh, Seong-Beom^c | Na, Duk L.^{a; b} | Suh, Mee Kyung^{a; b; *} | Seo, Sang Won^{a; b; h; i; j; *}

Affiliations: [a] Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea | [b] Neuroscience Center, Samsung Medical Center, Seoul, Korea | [c] Department of Neurology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea | [d] Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea | [e] Department of Neurology, Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Goyang, Korea | [f] Department of Neurology, Gachon University Gil Medical Center, Incheon, Korea | [g] Department of Neurology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Korea | [h] Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea | [i] Samsung Alzheimer Research Center and Center for Clinical Epidemiology Medical Center, Seoul, Korea | [j] Department of Intelligent Precision Healthcare Convergence, SAIHST, Sungkyunkwan University, Seoul, Korea

Correspondence: [*] Correspondence to: Sang Won Seo, MD, PhD, Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea. Tel.: +82 2 3410 6147; Fax: +82 2 3410 0052; E-mails: [email protected] or [email protected]; Mee Kyung Suh, PhD, Department of Neurology, Sungkyunkwan University School of Medicine, Samsung Medical Center, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea. Tel.: +82 2 3410 2735; Fax: +82 2 3410 2759; E-mail: [email protected].

Note: [1] These authors contributed equally to this work.

Abstract: Background:Primary progressive aphasia (PPA) is associated with amyloid-β (Aβ) pathology. However, clinical feature of PPA based on Aβ positivity remains unclear. Objective:We aimed to assess the prevalence of Aβ positivity in patients with PPA and compare the clinical characteristics of patients with Aβ-positive (A+) and Aβ-negative (A–) PPA. Further, we applied Aβ and tau classification system (AT system) in patients with PPA for whom additional information of in vivo tau biomarker was available. Methods:We recruited 110 patients with PPA (41 semantic [svPPA], 27 non-fluent [nfvPPA], 32 logopenic [lvPPA], and 10 unclassified [ucPPA]) who underwent Aβ-PET imaging at multi centers. The extent of language impairment and cortical atrophy were compared between the A+ and A–PPA subgroups using general linear models. Results:The prevalence of Aβ positivity was highest in patients with lvPPA (81.3%), followed by ucPPA (60.0%), nfvPPA (18.5%), and svPPA (9.8%). The A+ PPA subgroup manifested cortical atrophy mainly in the left superior temporal/inferior parietal regions and had lower repetition scores compared to the A–PPA subgroup. Further, we observed that more than 90% (13/14) of the patients with A+ PPA had tau deposition. Conclusion:Our findings will help clinicians understand the patterns of language impairment and cortical atrophy in patients with PPA based on Aβ deposition. Considering that most of the A+ PPA patents are tau positive, understanding the influence of Alzheimer’s disease biomarkers on PPA might provide an opportunity for these patients to participate in clinical trials aimed for treating atypical Alzheimer’s disease.

Keywords: Amyloid-β, biomarker, language, primary progressive aphasia, tau

DOI: 10.3233/JAD-210392

Journal: Journal of Alzheimer's Disease, vol. 84, no. 2, pp. 633-645, 2021