Loss of Functional Dentition is Associated with Cognitive Impairment

Article type: Research Article

Authors: Han, Ji Hyun^{a; 1} | Lee, Hyo-Jung^{b; 1} | Han, Ji Won^a | Suh, Seung Wan^a | Lee, Ju Ri^c | Byun, Seonjeong^a | Kim, Keun Suh^b | Kim, Sung Yeol^b | Lee, Jung-Tae^d | Yoo, Eunha^e | Chang, Na-Hee^f | Kim, Tae Hui^g | Kim, Ki Woong^{a; h; i; j; *}

Affiliations: [a] Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam, Korea | [b] Department of Periodontology, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea | [c] Samjung Hospital, Incheon, Korea | [d] Department of Periodontics, Dankook University College of Dentistry Jukjeon Dental Hospital, Yongin, Korea | [e] Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea | [f] Biomedical Research Institute, Seoul National University Bundang Hospital, Seongnam, Korea | [g] Department of Psychiatry, Yonsei University Wonju Severance Christian Hospital, Wonju, Korea | [h] Department of Psychiatry, Seoul National University, College of Medicine, Seoul, Korea | [i] Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Korea | [j] National Institute of Dementia, Seongnam, Korea

Correspondence: [*] Correspondence to: Ki Woong Kim, MD, PhD, Department of Neuropsychiatry, Seoul National University, College of Medicine, and Seoul National University Bundang Hospital, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, Republic of Korea. Tel.: +82 31 787 7432; Fax: +82 31 787 4058; E-mail: kwkimmd@snu.ac.kr.

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

Abstract: Background:Although tooth loss is known to increase the risk of cognitive impairment and dementia, few studies have investigated the association between functional teeth including rehabilitated lost teeth and cognitive function Objective:We investigated the associations of the numbers of functional teeth and functional occlusal units with cognitive impairment and cognitive function in late life. Methods:The current study was conducted as a part of the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD), a community-based elderly cohort study. We analyzed 411 participants who have agreed with the additional dental exam. Geriatric psychiatrists and neuropsychologists administered the Consortium to Establish a Registry for Alzheimer’s disease Assessment Packet Clinical and Neuropsychological Assessment Battery to all participants, and dentists examined their dental status. Results:Higher number of functional teeth (OR = 0.955, 95% CI = 0.914–0.997, p = 0.037) and higher number of functional occlusal units (OR = 0.900, 95% CI = 0.813–0.996, p = 0.042) were associated with lower odds of cognitive impairment. When we analyzed these relationships separated by the location of teeth, only the numbers of functional teeth (OR = 0.566, 95% CI = 0.373–0.857, p = 0.007) and functional occlusal units (OR = 0.399, 95% CI = 0.213–0.748, p = 0.004) in the premolar area were associated with lower odds of cognitive impairment. Conclusion:Loss of functional teeth and functional occlusal units (especially in the premolar region) were associated with increased cognitive impairment.

Keywords: Cognitive impairment, dental prosthesis, occlusal unit, tooth

DOI: 10.3233/JAD-190971

Journal: Journal of Alzheimer's Disease, vol. 73, no. 4, pp. 1313-1320, 2020