Abstract: PURPOSE: To evaluate the effects of anxiety and depression on the risk of periodontitis using Mendelian randomization (MR) method, and to analyze the prevalence and influencing factors of anxiety and depression symptoms in patients with periodontitis, so as to provide evidence for clinical prevention and treatment. METHODS: The data of 70 patients with periodontitis and 35 healthy controls who were treated in the Fourth Hospital of Changsha from August 2022 to August 2024 were collected.Hamilton Anxiety Rating Scale (HAMA) was used to assess the anxiety of the subjects. Hamilton Depression Rating Scale (HAMD) was used to assess symptoms of depression of the subjects, and potential risk factors were analyzed by logistic regression. Single nucleotide polymorphisms (SNP) were screened from the Genome-Wide Association Study (GWAS) database as instrumental variables. The independent SNP were screened according to the P-value threshold (P=5e-05) and the linkage unbalanced clustering method (window size 10 000 kb, r² threshold 0.001), and the data were coordinated. Five MR methods, including inverse variance weighted (IVW), were used to analyze the causal relationship between anxiety and depression on acute and chronic periodontitis. RESULTS: In the clinical case-control study, HAMA and HAMD scores of the periodontitis group were significantly higher than those of the control group (HAMA: P=0.006; HAMD: P=0.007). The incidence of anxiety in the periodontitis group was significantly higher than that in the control group (P=0.008), and the incidence of depression was also significantly higher (P=0.006). Logistic regression analysis revealed that anxiety, depression, and age ≥ 60 years were independent risk factors for periodontitis (P<0.05). MR analysis showed that anxiety was significantly positively correlated with acute periodontitis (IVW method, P =0.037), and depression was significantly positively correlated with acute periodontitis (IVW method, P=0.043), but neither was significantly associated with chronic periodontitis (P>0.05). The tests for pleiotropy and heterogeneity indicated that the analysis results were reliable (IVW method and MR Egger method, P>0.05 for both). CONCLUSIONS: There is significant correlation between anxiety and depression symptoms and periodontitis. It is recommended to consider the influence of psychological factors in clinical treatment of periodontitis.

Key words: Periodontitis, Mental health, Anxiety, Depression, Mendelian randomization, Single nucleotide polymorphism