The Association Between Temporomandibular Disorders and Suicide Ideation in a Representative Sample of the South Korean Population

Aims: To investigate in a representative sample of South Koreans (1) the prevalence of and associations between general pain, temporomandibular disorders (TMD), and suicide ideation (SI), and (2) whether the associations between general pain, TMD, and SI differ according to cancer history. Methods: Data were from the Fourth Korean National Health and Nutrition Examination Survey (KNHANES IV; N = 16,658). KNHANES IV participants provided reports regarding their cancer history, EQ-5D (a measure of health status from the EuroQoL Group), and TMD symptoms including clicking of one or both temporomandibular joints, pain, and mouth-opening limitation (MOL). Participants were assessed for any SI over the last 12 months, as a dependent variable. The independent variables were pain/discomfort (EQ-PD) reported by the subjects on the EQ-5D, severe TMD (tenderness or reduced jaw mobility once or more per week), and total TMD (occurrence of clicking, tenderness on palpation, or reduced jaw mobility [opening 30 mm] once or more per week). Demographic information (age and gender), socioeconomic status (income, education, occupation, and marital status), behavioral factors (smoking and binge drinking), and cancer history were evaluated as covariates. The association of TMD with SI was assessed by the prevalence ratio (PR) and 95% confidence intervals. Results: In fully adjusted models, elevated PRs for SI were observed for each pain condition (PR = 1.26 for total TMD, PR = 1.35 for severe TMD, and PR = 1.75 for EQ-PD). In the subgroup analyses by cancer history, the PRs were higher in the cancer history (+) group; the order of magnitude was severe TMD (PR = 2.20), EQ-PD (PR = 2.16), and total TMD (PR = 2.02). Conclusion: Pain conditions, including TMD pain, might aggravate SI among those with a cancer history. These findings add to a growing body of evidence indicating that TMD warrants further attention in relation to suicide. Keywords: epidemiology, pain, suicide, temporomandibular disorders