Relationship of tooth loss to mild cognitive impairment among middle-aged Mongolians: Mon-Timeline study

Abstract

Cognitive impairment is common in elderly people, so it is considered an ageing disorder. However, cognitive decline, including dementia, can also occur in middle-aged people. Cognitive impairment is associated with multiple risk factors. We hypothesised that tooth loss might also be a potential risk factor among Mongolians, as oral health problems are one of the significant health issues in Mongolia, especially in middle-aged people. In this cross-sectional study, we used the baseline data from the Mon-Timeline cohort study, including people older than 40 years of age (n=279). The amount of tooth loss was assessed by a trained researcher. Mild cognitive impairment (MCI) was defined as those participants scoring a total of £ 24 points based on the Mini-Mental State Examination (MMSE). Unadjusted analysis showed that having more tooth loss (>10) increased the risk of MCI by an odds ratio of 3.03 (1.49-6.17), as compared with having less tooth loss (£10). Even after adjusting for covariates, the association remained significant, suggesting that tooth loss is associated with MCI risk, independent of age, education, and other socioeconomic factors. There was no significant interaction effect of age in the association between tooth loss and MMSE scores. In conclusion, tooth loss may play a role in developing cognitive decline, especially in the early onset of dementia. Further studies are needed to investigate whether early tooth loss at younger ages is associated with dementia, especially among middle-aged people.