The relation between teeth loss and cognitive decline among Saudi population in the city of Riyadh: A pilot study

Teeth are necessary for sensory input to the brain during the chewing process, but how the decrease in this sensory input, due to loss of teeth, may cause weak memory and lead to cognitive decline is not well understood. This pilot public survey aiming to assess the correlation between the number of missing teeth, periodontal disease, and cognitive skill in the city of Riyadh.

A multicenter cross-sectional survey, targeting geriatric population aged ≥60 years, was performed in Riyadh City, Saudi Arabia. The Montreal Cognitive Assessment (MoCA) was conducted to all participants to assess their cognitive function. Assessment of oral health status was carried out, including the number of present dentation and their periodontal status. Community periodontal-index (CPI) was used to assess the periodontal condition. The primary variables were number of missing teeth, periodontal disease and MoCA test scores. Chi-square test and Pearson's correlation coefficients were computed and the significant P- value was set at <0.05.

Of 95 participants, overall, 57 (60%) and 38 (40%) were male and female, respectively, with a mean age of 65.67 ± 6.32 years. Females showed more significant cognitive decline than males (P < 0.001). Cognitive decline was significantly high in participants with low educational level 19 (95%), unemployment 41 (79%), and lower income people 26 (79%), while being cognitive intact was significantly higher in highly educated 13 (87%), retired 21 (62%), and higher income people 28 (74%) at (P < 0.001). An advanced age and greater number of missing teeth are associated with lower MoCA test scores. No statistical significant correlation with regard to periodontal disease and MoCA test scores.

Based on the preliminary data, positive correlation was confirmed when the number of missing teeth and cognitive skill were assessed. Therefore, larger, multi-center regional surveys are needed to investigate further this relationship.