Decreased Glucose Metabolism in Medial Prefrontal Areas is Associated with Nutritional Status in Patients with Prodromal and Early Alzheimer’s Disease

Article type: Research Article

Authors: Sugimoto, Taiki^{a; b; c} | Nakamura, Akinori^d | Kato, Takashi^d | Iwata, Kaori^d | Saji, Naoki^a | Arahata, Yutaka^e | Hattori, Hideyuki^f | Bundo, Masahiko^g | Ito, Kengo^{d; h} | Niida, Shumpei^b | Sakurai, Takashi^{a; *} | MULNIAD study group

Affiliations: [a] Center for Comprehensive Care and Research on Memory Disorders, National Center for Geriatrics and Gerontology, Obu, Japan | [b] Medical Genome Center, National Center for Geriatrics and Gerontology, Obu, Japan | [c] Department of Community Health Sciences, Kobe University, Graduate School of Health Sciences, Kobe, Japan | [d] Department of Clinical and Experimental Neuroimaging, National Center for Geriatrics and Gerontology, Obu, Japan | [e] Department of Neurology, National Centerfor Geriatrics and Gerontology, Obu, Japan | [f] Department of Psychiatry, National Center for Geriatrics and Gerontology, Obu, Japan | [g] Department of Neurosurgery, National Center for Geriatrics and Gerontology, Obu, Japan | [h] Department of Radiology, National Center for Geriatrics and Gerontology, Obu, Japan

Correspondence: [*] Correspondence to: Takashi Sakurai, 7-430 Morioka, Obu, Aichi, 474-8511, Japan. Tel.: +81 562 46 2311; Fax: +81 562 46 8394; E-mail: tsakurai@ncgg.go.jp.

Abstract: Background:Weight loss is frequently observed in patients with Alzheimer’s disease (AD); however, the underlying mechanisms are not well understood. Objects:To clarify the associations between nutritional status and AD-related brain changes using Pittsburgh Compound-B (PiB)-PET, fluorodeoxyglucose (FDG)-PET, and structural MRI. Methods:The subjects were 34 amyloid-β (Aβ)-positive individuals with mild cognitive impairment or early AD (prodromal/early AD), and 55 Aβ-negative cognitively normal (CN) subjects who attended the Multimodal Neuroimaging for AD Diagnosis (MULNIAD) study. Nutritional status of the subjects was assessed by body mass index and waist to height ratio (waist circumference/height). The associations between nutritional status and brain changes were examined by multiple regression analysis using statistical parametric mapping. Results:In the prodromal/early AD group, nutritional status was significantly positively correlated with regional cerebral glucose metabolism (rCGM) in the medial prefrontal cortices, while different topographical associations were seen in the CN group, suggesting these changes were AD-specific. Aβ deposition and gray matter volume were not significantly associated with nutritional status. Sub-analysis in the prodromal/early AD group demonstrated that fat mass index, but not fat-free mass index, was positively correlated with rCGM in the medial prefrontal areas. Conclusion:This present study provides preliminary results suggesting that hypometabolism in the medial prefrontal areas is specifically associated with AD-related weight loss, and decrease in fat mass may have a key role.

Keywords: Alzheimer’s disease, composition, ¹⁸F fluorodeoxyglucose, Pittsburgh Compound B, magnetic resonance imaging, nutritional status, positron-emission tomography

DOI: 10.3233/JAD-170257

Journal: Journal of Alzheimer's Disease, vol. 60, no. 1, pp. 225-233, 2017