Periodontitis Is Associated with Cognitive Impairment in Elderly Koreans: Results from the Yangpyeong Cohort Study

Abstract

OBJECTIVES: To investigate the association between periodontitis and cognitive impairment in elderly Koreans. DESIGN: Cross-sectional study with age-and sex-matched case-control selection. SETTING: The Yangpyeong cardiovascular cohort (YCC), a part of the Korean Genome Epidemiologic Study (KoGES), Yangpyeong, South Korea. PARTICIPANTS: Individuals with cognitive impairment (n = 65) and cognitively normal controls (n = 124) aged 60 and older from the YCC. MEASUREMENTS: Alveolar bone loss was assessed on dental panoramic radiographs to categorize the cumulative history of periodontitis (HOP) into three groups: normal, moderate periodontitis, severe periodontitis. The Mini-Mental State Examination (MMSE) was used to categorize participants as cognitively normal or cognitively impaired. Age-and sex-matched conditional logistic regression models were used for analysis. Confounders considered in the analysis were age, sex, drinking, smoking, exercise, total cholesterol, total protein, body mass index, fasting plasma glucose, intima-media thickness, hypertension medication, and depression. RESULTS: Participants with HOP were more likely to have cognitive impairment than those without (odds ratio = 2.14, 95% confidence interval = 1.04-4.41). The interaction effect of smoking and exercise on periodontitis highlighted the link. CONCLUSION: Periodontitis was independently associated with cognitive impairment after controlling for various confounders. Further longitudinal research is needed to determine whether periodontitis plays a role in cognitive decline in older adults.This work was supported by the Korea Centers for Disease Control and Prevention, Ministry of Health and Welfare (2010E7101300), Seoul, Korea; a grant from the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Education, Science and Technology (2013-062881), and the NRF Grant through the Oromaxillofacial Dysfunction Research Center for the Elderly (2014-050477) at Seoul National University, Seoul, Korea. Ms. Shin and Dr. Ahn were supported by grants from the Brain Korea 21 at Seoul National University School of Dentistry in Korea